JP2007294813A - Measurement / inspection method, measurement / inspection apparatus, exposure apparatus, and device manufacturing processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve a high precision and high-throughput multiple-exposure, and to improve yield of device manufacturing. <P>SOLUTION: When a line width failure is found at step 307, a pattern reticle in which the failure has occurred is identified (step 309). From a difference between the line width estimated from a control error when the pattern is transferred and actual line width, data on how processing by other processing devices is performed, and the like, it is determined whether the aberration of a projection optical system has caused the line width failure (steps 311 to 319). When the aberration of the projection optical system has caused the line width failure, the aberration is measured while other causes are eliminated, and the aberration of individual optical system is adjusted for each exposure light. After the adjustment, for remaining aberration, the aberration of the optical system common to all exposure lights is adjusted. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a measurement / inspection method, a measurement / inspection apparatus, an exposure apparatus, and a device manufacturing processing apparatus. More specifically, for example, a semiconductor element, a liquid crystal display element, an imaging element such as a CCD (Charge Coupled Device), a thin film magnetic head, and the like. The present invention relates to a measurement / inspection method, a measurement / inspection apparatus, an exposure apparatus, and a device manufacturing processing apparatus.

  Conventionally, for the purpose of improving the resolution of a device pattern transferred onto a substrate, a so-called multiple exposure method in which the patterns of two or more reticles are superimposed and transferred onto the same region on the substrate is often used. (For example, refer to Patent Document 1). If this multiple exposure method is used, deterioration of the pattern image due to the optical proximity effect or the like can be reduced, and a highly accurate device pattern can be transferred and formed. Recently, a multiple exposure method has been proposed in which images of a plurality of different patterns are projected onto a substrate almost simultaneously using different exposure lights. According to this method, images of a plurality of patterns can be transferred onto the substrate almost simultaneously, so that an improvement in throughput can be expected. In this multiple exposure method, in order to accurately transfer each pattern onto a substrate using a plurality of exposure lights via individual patterns, it is necessary to reduce the respective aberrations of the optical system that guides each exposure light. However, when there is a common optical system for a plurality of exposure lights, it is difficult to adjust the aberration of the optical system.

JP-A-10-209039

  From a first aspect, the present invention includes a third optical system that guides both the first exposure light guided by the first optical system and the second exposure light guided by the second optical system onto the substrate. And a measurement inspection method for measuring and inspecting optical characteristic information of an exposure apparatus that exposes the substrate with the first and second exposure lights.

  According to this, multiplexing using the first exposure light guided onto the substrate by the first optical system and the third optical system and the second exposure light guided onto the substrate by the second exposure light and the third optical system. A measurement / inspection result of optical characteristic information of an exposure apparatus capable of exposure can be acquired.

  From a second viewpoint, the present invention is a measurement / inspection apparatus characterized in that the optical characteristic information of the exposure apparatus is measured and inspected by the measurement / inspection method of the present invention. Such a measurement / inspection apparatus performs a measurement / inspection using the measurement / inspection method of the present invention, and thus includes a first optical system, a second optical system, and a third optical system for guiding the first exposure light and the second exposure light, It is possible to obtain a measurement / inspection result of optical characteristic information of an exposure apparatus capable of multiple exposure using both exposure lights.

  From a third aspect, the present invention provides a first optical system that guides first exposure light, a second optical system that guides second exposure light, and the first exposure light guided by the first optical system. A third optical system that guides the second exposure light guided by the second optical system onto the substrate and guides the substrate with the first exposure light and the second exposure light. An exposure apparatus that exposes, based on optical characteristic information detected by a predetermined measurement inspection process, a first optical characteristic related to the irradiation of the first exposure light and a second optical characteristic related to the irradiation of the second exposure light. The exposure apparatus includes a control device that controls at least one of the above.

  According to this, at least one of the first optical characteristic related to the irradiation of the first exposure light and the second optical characteristic related to the irradiation of the second exposure light is controlled based on the optical characteristic information detected by the predetermined measurement inspection process. In this state, since the multiple exposure is performed using the first exposure light and the second exposure light guided onto the substrate by each optical system, multiple exposure with high accuracy and high throughput becomes possible.

  From the fourth viewpoint, the present invention is a device manufacturing processing apparatus for manufacturing a device using the exposure apparatus of the present invention. In such a case, high-precision and high-throughput multiple exposure using the exposure apparatus of the present invention is possible, so that the yield of device production can be improved.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 shows a schematic configuration of a device manufacturing processing system according to an embodiment of the present invention. As shown in FIG. 1, a device manufacturing processing system 1000 is built in a device manufacturing factory to process semiconductor wafers and manufacture micro devices on the wafers. As shown in FIG. 1, the device manufacturing processing system 1000 includes an exposure apparatus 100, a track 200 disposed adjacent to the exposure apparatus 100, a management controller 160, an analysis apparatus 500, and a host system 600. And a device manufacturing processing apparatus group 900.

  The exposure apparatus 100 is an apparatus that transfers a device pattern to a wafer coated with a photoresist. FIG. 2 shows a schematic configuration of the exposure apparatus 100. The exposure apparatus 100 holds the illumination system 10 that emits two coherent exposure lights IL1 and IL2 and the reticle R1 illuminated by the exposure light IL1 in a vacuum suction manner via the reticle holder RH, and illuminates with the exposure light IL2. A portion of the device pattern formed on the wafer W is applied to the reticle stage RST that holds the reticle R2 to be vacuum-sucked via another reticle holder RH and the reticles R1 and R2 illuminated by the exposure lights IL1 and IL2, respectively. Both-side telecentric projection optical system PL that projects onto the exposure surface, wafer stage WST that holds wafer W to be exposed, and main controller 20 that performs overall control thereof are provided.

  A device pattern including a circuit pattern and the like is formed on each of the reticles R1 and R2. A composite pattern of the device patterns of the reticles R1 and R2 is transferred and formed on the exposed surface of the wafer W. These device patterns can be various combinations. For example, the device pattern of the reticle R1 can be a periodic device pattern, and the device pattern of the reticle R2 can be a device pattern with low periodicity. The device pattern of the reticle R1 can be a basic device pattern, and the device pattern of the reticle R2 can be an auxiliary pattern for OPC (optical proximity effect correction). If the device pattern is divided in this way, the interval between adjacent patterns can be widened, so that the optical proximity effect is reduced.

  The coherent exposure light IL1 emitted from the illumination system 10 is irradiated onto a part of the pattern forming surface of the reticle R1 held by the reticle stage RST, and the coherent exposure light IL2 emitted from the illumination system 10 is also used as the reticle. A part of the pattern forming surface of reticle R2 held on stage RST is irradiated. These irradiation areas are referred to as illumination areas IAR1 and IAR2, respectively.

  The exposure lights IL1 and IL2 that have passed through the illumination areas IAR1 and IAR2, respectively, enter a part of the exposed surface (wafer surface) of the wafer W held on the wafer stage WST via the projection optical system PL. Therefore, the projection images of the device patterns in the illumination areas IAR1 and IAR2 are formed so as to overlap with this area. An area where this projection image is formed is defined as an exposure area IA. Since the photoresist is coated on the exposed surface of the wafer W, the combined pattern of the two projected images is transferred to the portion corresponding to the exposure area IA.

  Here, consider an XYZ coordinate system in which the coordinate axis along the optical axis of the projection optical system PL is the Z axis. Wafer stage WST that holds wafer W via wafer holder WH can move on the XY plane, shift the exposed surface of wafer W in the Z-axis direction, and rotate in the θx (rotation about the X-axis) direction, θy. It is possible to rotate in the direction (rotation around the Y axis). The reticle stage RST that holds the reticles R1 and R2 can be moved with a long stroke in the Y-axis direction, can be finely moved in the X-axis direction, and can be rotated in the θz direction. Position information of X, Y, θx, θy, θz of wafer stage WST is constantly measured by an interferometer or the like, and is sent to main controller 20.

  In addition, reticle stage RST can move in the XY plane in synchronization with wafer stage WST that holds wafer W. Further, reticle stage RST actually includes one main stage, a substage that holds reticle R1 via reticle holder RH, and a substage that holds reticle R2 via another reticle holder RH. I have. The two sub-stages are placed on the main stage, and are configured to be able to adjust their relative position and relative posture with respect to the main stage. By this adjustment, it is possible to correct the rotation of the reticles R1 and R2 in the θz direction and to keep the Z position of the pattern forming surface in the illumination areas IAR1 and IAR2 constant. The positional information of X, Y, Z, θx, θy, and θz of the main stage and the two substages is constantly measured by an interferometer or the like and is sent to the main controller 20. Hereinafter, the position information of the main stage and the two substages will be collectively referred to as the position information of the reticle stage RST.

  By synchronous scanning of the reticle stage RST and the wafer stage WST at a speed corresponding to the projection magnification of the projection optical system PL, the device pattern on the reticles R1 and R2 is synchronized with passing through the illumination areas IAR1 and IAR2. The exposed surface of the wafer W passes through the exposure area IA. As a result, all device patterns on the reticles R1 and R2 are transferred to a partial region (shot region) on the exposed surface of the wafer W. In exposure apparatus 100, the device pattern on reticles R1 and R2 is changed to wafer W by repeating the above-described relative synchronous scanning of reticle stage RST and stepping of wafer stage WST holding wafer W with respect to exposure lights IL1 and IL2. Transferred to a plurality of upper shot areas. That is, the exposure apparatus 100 is a scanning exposure (step-and-scan) type exposure apparatus that performs so-called multiple exposure (double exposure).

  As shown in FIG. 3, the main controller 20 controls an exposure amount control system EC1 that controls the intensity (exposure amount) of the exposure light IL1, and an exposure amount control system EC2 that controls the intensity (exposure amount) of the exposure light IL2. And position control of reticle stage RST, position control of wafer stage WST, synchronous control of both stages RST and WST, and autofocus / leveling control for matching the exposed surface of wafer W within the depth of focus of projection optical system PL ( Hereinafter, it includes a stage control system SC that simply performs focus control and the like, and a lens control system LC that controls the imaging state of the projection optical system PL.

  As shown in FIG. 3, the exposure amount control system EC1 performs feedback control based on a detection value of an exposure amount sensor (not shown) capable of detecting the intensity of the exposure light IL1, and commands the intensity of the exposure light IL1. The value is output to the illumination system 10. The exposure amount control system EC2 performs feedback control based on a detection value of an exposure amount sensor (not shown) capable of detecting the intensity of the exposure light IL2, and sends a command value for the intensity of the exposure light IL2 to the illumination system 10. Output. The illumination system 10 irradiates the exposure lights IL1 and IL2 with the intensity according to the command value.

  The stage control system SC performs feedback control based on the position information of the reticle stage RST, and outputs a drive command for the reticle stage RST. Stage control system SC performs feedback control based on the position information of wafer stage WST, and outputs a drive command for wafer stage WST. As described above, the stage control system SC can perform the synchronization control of both the stages RST and WST and the focus / leveling control based on the position information of the both stages RST and WST. That is, the stage control system SC is a control system that performs synchronous control of both the stages RST and WST, and the rotation amount around the Z position, the X axis, and the Y axis of the stage position (exposed surface of the wafer W). And a focus control system for controlling the camera.

  The synchronous control system performs feedback control based on the positional information of both stages WST and RST so that both stages RST and WST are synchronously scanned under the XYZ coordinate system during scanning exposure. RST drive command is output.

  The exposure apparatus 100 is provided with a multi-point AF (autofocus) sensor (not shown) that detects a focus / leveling shift of the exposed surface of the wafer W at a plurality of detection points. As shown in FIG. 3, the stage control system SC detects the surface position of the exposed surface of the wafer W at, for example, nine detection points (9 channels) among the plurality of detection points of the multipoint AF sensor. By performing feedback control so that the exposed surface of the wafer W corresponding to the exposure area IA matches the image surface of the projection optical system PL, a drive command in the Z-axis direction, θx, θy direction of the wafer stage WST is issued. Output.

  Further, although not shown in FIG. 3, the exposure apparatus 100 includes a pattern forming surface of the reticle R1 in a region including at least the illumination region IAR1 and a pattern forming surface of the reticle R2 in a region including at least the illumination region IAR2. A multi-point AF sensor (not shown) for detecting the surface position is provided. The focus control system of the stage control system SC controls the surface position of the pattern formation surface of the reticle R1 in the illumination area IAR1 by driving the substage that holds the reticle R1 based on the information from the multipoint AF sensor. It is also possible to control the surface position of the pattern forming surface of the reticle R2 in the illumination area IAR2 by driving the substage that holds the reticle R2.

  Projection optical system PL is a double-sided telecentric optical system including optical systems PL1, PL2, and PL3 including a plurality of refractive optical elements (lens elements) and a plurality of mirrors. The exposure light IL1 that passes through the illumination area IAR1 is guided to the mirror by the optical system PL1, is reflected by the plurality of mirrors, enters the optical system PL3, and is guided to the exposed surface of the wafer W. On the other hand, the exposure light IL2 that has passed through the illumination area IAR2 enters the optical system PL2, is guided to the mirror, is reflected by a plurality of mirrors (including half mirrors), is incident on the optical system PL3, and is incident on the wafer W. Guided to the exposure surface. As a result, partial inverted images of the patterns in the illumination areas IAR1 and IAR2 are projected onto the exposure area IA at a predetermined magnification.

  The optical systems PL1 to PL3 are configured to be able to adjust respective imaging characteristics by driving an internal movable lens element that can be driven with six degrees of freedom. The lens control system LC can individually adjust the imaging characteristics of the optical system PL1 of the projection optical system PL, the imaging characteristics of the optical system PL2, and the imaging characteristics of the optical system PL3. The lens control system LC monitors the state of the optical systems PL1 to PL3, such as atmospheric pressure, the temperature in the chamber of the exposure apparatus 100, the exposure amount, the temperature of the lens of the projection optical system PL, and the like even during scanning exposure. Based on the result (measured value), the magnification fluctuation amount and the focus fluctuation amount of the projection optical system PL are calculated, and based on the fluctuation amounts, driving commands for the optical systems PL1, PL2, and PL3 are output. Thereby, the best focus position in the projection optical system PL is maintained at the target value.

  The operation of the exposure apparatus 100 can be adjusted to some extent by changing the value of the apparatus parameter. Examples include control system parameters such as gain in feedback control of the various control systems, illumination conditions such as coherence factor in the illumination system 10, and the like. The illumination conditions can be set individually for the exposure light IL1 and the exposure light IL2, and are determined by the resolution required for the pattern to be exposed.

[Control system parameters]
Control system parameters are roughly classified into adjustment system parameters that require device adjustment by temporarily stopping the process when changing the set values, and non-adjustment system parameters that do not require device adjustment.

  Some representative examples of the adjustment system parameters will be described. First, in relation to the exposure amount control system, adjustment parameters of an exposure amount sensor (not shown) for detecting the exposure amount and adjustment of an illuminance measurement sensor (not shown) for measuring the intensity of illumination light on the exposed surface of the wafer W are adjusted. There are parameters. Further, in the case of the synchronous control system, the movable mirror bending correction provided on the stage WST and RST that holds the wafer W and the reticle R in order to reflect the laser beam from the interferometer for measuring the position of the stage WST and RST. Parameters such as the coefficient value of the correction function, position loop gain of feedback control, speed loop gain, integration time constant, and the like. In the focus control system, focus offset, which is an offset adjustment value for focus control when aligning the wafer surface at the time of exposure with the best imaging surface by the projection optical system PL, and the wafer surface at the time of exposure and the projection optical system PL. Leveling adjustment parameters to match the best imaging plane of the sensor, linearity of the position detection element (PSD) that is the sensor of each detection point of the multipoint AF sensor, offset between sensors, detection reproducibility of each sensor, between channels There are an offset, an AF beam irradiation position (ie, a detection point) on the wafer, and other parameters related to AF surface correction. These adjustment system parameter values all need to be adjusted by calibration or trial operation of the apparatus.

  Next, some representative examples of the non-adjustment system parameters will be described. First, in relation to the exposure amount control system, for example, there are parameters related to selection of ND filters in the illumination system 10 and exposure amount target values. Further, as for the synchronization control system, for example, there is a scanning speed. In the focus control system, for example, there are a focus sensor selection state for 9 channels, a parameter related to a focus step correction map, which will be described later, a fine adjustment amount of a focus offset, a scan direction in an edge shot of the wafer outer edge, and the like. These parameter setting values are parameters that can be changed without calibrating the apparatus, and are often specified by the exposure recipe. Note that the ND filter is selected based on the result of an average power check that is performed only once with an exposure amount target value set appropriately (for example, minimum) at the start of exposure for a certain wafer W. Depending on the selection of the ND filter, the scan speed is also finely adjusted to some extent.

  The exposure amount related parameters can be set separately for the exposure lights IL1 and IL2.

  The line width and transfer position of the device pattern transferred and formed on the wafer W deviate from the design value due to exposure control, synchronization accuracy, focus, and lens control errors. Therefore, in the exposure apparatus 100, time-series data (exposure amount trace data) of control amounts related to the exposure amount errors obtained from the exposure amount control systems EC1 and EC2, and synchronization accuracy errors obtained from the synchronization control system of the stage control system SC. Control amount time series data (synchronization accuracy trace data), control amount time series data (focus trace data) obtained from the focus control system of the stage control system SC, and lens control system LC The time series data (lens trace data) of the control amount related to the lens control error is logged, and the data is used for analysis and evaluation of the pattern line width and the like.

  The projection optical system PL has wavefront aberration. Due to this wavefront aberration, the wavefront of the parallel light flux passing through the projection optical system PL deviates from the ideal wavefront. This deviation of the wavefront causes a positional deviation of the imaging position on the image plane of light generated from one point on the object surface. The optical systems PL1, PL2, and PL3 constituting the projection optical system PL are configured to be able to adjust the wavefront aberration by driving the movable lens elements included in each of them under the control of the lens control system LC. .

  The wavefront aberration of the projection optical system PL can be expressed by Seidel aberration or Zernike polynomial. Among them, the Zernike polynomial is suitable for expressing wavefront aberration of higher order components. The Zernike polynomial is a real polynomial related to the pupil coordinates (ρ, θ) of the projection optical system PL, as shown by the following equation.

ツェルニケ多項式は、直交系であるから、各項の係数Ｚ_iを独立に決定することができる。ｉを適当な値で切ることはある種のフィルタリングを行うことに対応する。なお、一例として第１項〜第３７項までのｆ_i（ｆ_i（ρ，θ）：動径ρ、角度θを独立変数とする動径多項式）を係数Ｚ_iとともに例示すると、次の表１のようになる。但し、表１中の第３７項は、実際のツェルニケ多項式では、第４９項に相当するが、本明細書では、ｉ＝３７の項（第３７項）として取り扱うものとする。すなわち、本発明において、ツェルニケ多項式の項の数は、特に限定されるものではない。

Since the Zernike polynomial is an orthogonal system, the coefficient Z _i of each term can be determined independently. Cutting i by an appropriate value corresponds to performing some kind of filtering. As an example, f _i (f _i (ρ, θ): radial polynomial having radial ρ, angle θ as an independent variable) from the first term to the 37th term together with the coefficient Z _i is shown in the following table. It becomes like 1. However, the 37th term in Table 1 corresponds to the 49th term in the actual Zernike polynomial, but is treated as a term of i = 37 (the 37th term) in this specification. That is, in the present invention, the number of terms of the Zernike polynomial is not particularly limited.

ツェルニケ多項式のそれぞれの項は光学収差に対応する。しかも低次の項(ｉの小さい項)は、ザイデル収差にほぼ対応する。例えば、ツェルニケ係数Ｚ₇、Ｚ₈（Ｚ₇、Ｚ₈は直交関係）は、３次のコマ収差に対応し、Ｚ₁₄、Ｚ₁₅は、５次のコマ収差に対応する。これらのコマ収差は、動径多項式が奇関数であるいわゆる奇関数収差とも呼ばれている。ウエハＷ上に形成される像面では、パターンの横ずれ、焦点深度の低減、パターン非対称性の原因となる。また、ツェルニケ係数Ｚ₄は、デフォーカスに対応し、Ｚ₉は、４次の球面収差に対応する。これらの収差は、動径多項式が偶関数であるいわゆる偶関数収差とも呼ばれている。

Each term in the Zernike polynomial corresponds to an optical aberration. Moreover, the low-order terms (terms with a small i) substantially correspond to Seidel aberration. For example, Zernike coefficients Z ₇ and Z ₈ (Z ₇ and Z ₈ are orthogonal) correspond to third-order coma, and Z ₁₄ and Z ₁₅ correspond to fifth-order coma. These coma aberrations are also called so-called odd function aberrations in which the radial polynomial is an odd function. On the image plane formed on the wafer W, it causes a lateral shift of the pattern, a reduction of the focal depth, and a pattern asymmetry. The Zernike coefficient Z ₄ corresponds to defocus, and Z ₉ corresponds to fourth-order spherical aberration. These aberrations are also called so-called even function aberrations in which the radial polynomial is an even function.

  Since this Zernike polynomial can handle the amount of aberration at an arbitrary position on the image plane independently of the position coordinate, it can be said that it is suitable for evaluating the aberration of the projection optical system PL. If the lens elements of the optical systems PL1, PL2, and PL3 are driven under the control of the lens control system LC constituting the main controller 20, the wavefront aberration of the projection optical system PL, that is, the Zernike coefficients 1st to 37th terms. The magnitude of the aberration changes. When the magnitudes of the aberrations from the first term to the 37th term change, the imaging performance sensitive to the aberration of each term changes. Since the wavefront aberration is different at each point in the exposure area IA (image plane), the state of change in the imaging performance in the exposure area IA is also different for each point. The optical elements of the optical systems PL1 to PL3 need to be adjusted so that the imaging characteristics in the exposure area IA are as uniform as possible, that is, the wavefront aberration is as uniform as possible in the exposure area IA.

  The illumination system 10 can finely adjust the wavelengths of the exposure lights IL1 and IL2 under the control of the exposure control systems EC1 and EC2 of the main controller 20. The exposure apparatus 100 is also provided with an uneven illuminance sensor (not shown).

  The main controller 20 is a computer system that controls various components of the exposure apparatus 100 as described above. The main controller 20 is connected to a communication network constructed in the device manufacturing processing system 1000, and can send and receive data to and from the outside via the communication network.

[truck]
The track 200 is disposed in contact with a chamber (not shown) surrounding the exposure apparatus 100. The track 200 mainly carries in and out the wafers with respect to the exposure apparatus 100 by a transfer line provided inside.

[Coater / Developer]
In the track 200, a coater / developer (C / D) 110 for applying and developing a resist is provided. The C / D 110 applies and develops a photoresist on the wafer W. The C / D 110 can observe these processing states and record the observation data as log data. Examples of observable processing states include resist coating film thickness uniformity, development module processing, PEB (Post-Exposure-Bake) temperature uniformity (hot plate temperature uniformity), wafer heating history management (after PEB processing) There are various states of avoiding overbaking and cooling plate. The processing state of the C / D 110 can be adjusted to some extent by setting the apparatus parameters. Such apparatus parameters include, for example, parameters related to uneven application of resist on the wafer W, set temperature, rotation speed of the wafer W, resist dropping amount and dropping interval, and the like.

  The C / D 110 can operate independently of the exposure apparatus 100 and the wafer measurement / inspection instrument 120. The C / D 110 is disposed along the transport line of the track 200. Therefore, the wafer W can be transferred between the exposure apparatus 100 and the C / D 110 by this transfer line. Further, the C / D 110 is connected to a communication network in the device manufacturing processing system 1000, and can send and receive data to and from the outside. For example, the C / D 110 can output information on the process (information such as the trace data).

[Wafer measurement and inspection equipment]
In the track 200, a composite wafer measurement / inspection instrument 120 capable of performing various measurement / inspections on the wafer W before and after the exposure of the wafer W by the exposure apparatus 100 (that is, before and after) is provided. ing. Wafer measurement / inspection instrument 120 can operate independently of exposure apparatus 100 and C / D 110. The wafer measurement / inspection instrument 120 includes a control device that can operate independently from the control device of the exposure apparatus 100 and the C / D 110. The wafer measurement / inspection instrument 120 performs a pre-measurement / inspection process for performing measurement before exposure and a post-measurement / inspection process for performing measurement after exposure. Note that the wafer measurement / inspection instrument 120 may perform only one of the pre-measurement / inspection process and the post-measurement / inspection process. Further, separate measurement / inspection instruments may be provided for the pre-measurement / inspection process and the post-measurement / inspection process.

  In the pre-measurement inspection process, before the wafer W is transferred to the exposure apparatus 100, the surface shape of the exposed surface of the wafer W is measured, the foreign matter on the wafer W is inspected, and the resist film on the wafer W is inspected. The wafer measurement / inspection instrument 120 can output the results of the preliminary measurement / inspection to the outside via a communication network in the system.

  On the other hand, in the post measurement inspection process, the line width and overlay error of the resist pattern on the wafer W after exposure (post facto) transferred by the exposure apparatus 100 and developed by the C / D 110, the wavefront aberration of the projection optical system PL, Measurement of illumination unevenness, wafer film inspection, wafer defect / foreign particle inspection, etc. Here, the wafer film inspection includes inspection of a film formed on the wafer W, film thickness unevenness, film defect, foreign matter, scratch, and the like.

  Further, the wafer measurement / inspection instrument 120 is configured to measure the relative positional deviation amount of the aberration measurement mark transferred and formed on the test wafer for the aberration measurement of the projection optical system PL as will be described later. Has been.

  Also, the measurement state of the wafer measurement / inspection instrument 120 (for example, data that affects measurement errors such as alignment of residual components when aligning the wafer W for measurement) is used as log data. It can be recorded. This log data can also be output to the outside via a communication network. The wafer measurement / inspection instrument 120 can also adjust the measurement conditions to some extent by changing the setting of the apparatus parameters. Such apparatus parameters include, for example, parameters relating to the alignment of the wafer W, which is a precondition for measurement, parameters relating to the focus state of the sensor, selection of wafers to be measured, and parameters relating to selection of measurement shots. .

  The wafer measurement / inspection instrument 120 is disposed along the transport line of the track 200. Therefore, the wafer W can be transferred between the exposure apparatus 100, the C / D 110, and the wafer measurement / inspection instrument 120 by this transfer line. That is, the exposure apparatus 100, the track 200, and the wafer measurement / inspection instrument 120 are connected in-line to each other. Here, the in-line connection means that the apparatuses and the processing units in each apparatus are connected via a transfer device for automatically transferring the wafer W such as a robot arm or a slider. By this in-line connection, the transfer time of the wafer W among the exposure apparatus 100, the C / D 110, and the wafer measurement / inspection instrument 120 can be remarkably shortened.

  The exposure apparatus 100, the C / D 110, and the wafer measurement / inspection instrument 120 which are connected in-line can be regarded as one substrate processing apparatus (100, 110, 120) as a unit. The substrate processing apparatus (100, 110, 120) applies a photosensitive agent such as a photoresist to the wafer W, and projects and exposes images of the patterns of the reticles R1 and R2 on the wafer W coated with the photosensitive agent. An exposure process to be performed, and a development process to develop the wafer W after the exposure process is performed. Details of these steps will be described later.

  In the device manufacturing processing system 1000, a plurality of exposure apparatuses 100, C / Ds 110, and wafer measurement / inspection instruments 120, that is, substrate processing apparatuses (100, 110, 120) are provided. Each substrate processing apparatus (100, 110, 120) and device manufacturing processing apparatus group 900 is installed in a clean room in which temperature and humidity are controlled. In addition, the apparatuses are connected so that data communication can be performed via a predetermined communication network (for example, LAN: Local Area Network). This communication network is a so-called intranet communication network provided for a customer's factory, business office or company.

  In the substrate processing apparatus (100, 110, 120), a plurality of wafers W (for example, 20 wafers) are processed as one unit (referred to as a lot). In the device manufacturing processing system 1000, the wafer W is processed into a product by processing one lot as a basic unit. Therefore, the wafer process in the device manufacturing processing system 1000 is also referred to as lot processing.

  In this device manufacturing processing system 1000, the wafer measurement / inspection instrument 120 is placed in the track 200 and connected in-line with the exposure apparatus 100 and the C / D 110. However, these are arranged outside the track 200 and exposed. The apparatus 100 and the C / D 110 may be configured offline.

  As hardware for realizing the information processing apparatus of the wafer measuring and inspecting instrument 120 described above, for example, a personal computer can be employed. In this case, it is realized by executing a program executed by a CPU (not shown) of the information processing apparatus. The analysis program is supplied by a medium (information recording medium) such as a CD-ROM, and is executed in a state installed in a personal computer (PC).

[Analyzer]
The analysis apparatus 500 is an apparatus that operates independently of the exposure apparatus 100 and the track 200. The analysis apparatus 500 is connected to a communication network in the device manufacturing processing system 1000, and can send and receive data to and from the outside. The analysis apparatus 500 collects various data (for example, processing contents of the apparatus) from various apparatuses via the communication network, and analyzes data related to processes on the wafer. As hardware for realizing such an analysis apparatus 500, for example, a personal computer can be employed. In this case, the analysis process is realized by executing an analysis program executed by a CPU (not shown) of the analysis apparatus 500. This analysis program is supplied by a medium (information recording medium) such as a CD-ROM and is executed in a state installed in a PC.

  The analysis apparatus 500 can optimize the wavefront aberration of the projection optical system PL. Data relating to the wavefront aberration of the projection optical system PL measured by the wafer measurement / inspection instrument 120 is stored in a storage device (not shown) of the analysis apparatus 500. In addition to the measurement data relating to the wavefront aberration of the projection optical system PL collected from the wafer measurement / inspection instrument 120, this data includes the current data of the movable lens elements of the optical systems PL1 to PL3 of the projection optical system PL collected from the exposure apparatus 100. Information on driving positions and driving ranges (lens element driving ranges) of these movable lens elements are included.

  The analysis apparatus 500 calculates the wavefront aberration of the projection optical system PL, that is, the magnitudes of the first to 37th terms of the Zernike term based on the measurement data relating to the wavefront aberration. The analysis device 500 includes a Zernike term size (that is, wavefront aberration data), a lens element driving range, a wavefront aberration change table with respect to the driving amount of the lens element, an imaging performance change table with respect to the wavefront aberration, and an imaging performance. Error tolerance values are input, and using them, based on the wavefront aberration data calculated from the measurement results of the wafer measuring and inspecting instrument 120, the adjustment values of the driving position of the movable lens element and the exposure wavelength, the wafer stage WST The attitude adjustment value, residual error, and predicted imaging performance after driving are output. The driving position of the movable lens element is sent to the exposure apparatus 100. The lens control system of the main controller 20 of the exposure apparatus 100 drives the movable lens element to the driving position sent to adjust the wavefront aberration of the projection optical system PL, and offsets for attitude control of the wafer stage WST. The value is changed or the wavelengths of the exposure lights IL1 and IL2 are finely adjusted to bring the imaging performance close to the target value.

[Wavefront aberration change table]
The wavefront aberration change table shows the change in the unit adjustment amount of the adjustment parameter that affects the formation state of the projection image of the pattern on the reticle R, at a plurality of measurement points in the field of view of the projection optical system PL (that is, in the exposure area IA). It is the change table which consists of the data group which arranged the image formation performance corresponding to each, for example, the data which show the relationship with the variation | change_quantity of the coefficient of the 1st term-the 37th term of the above-mentioned Zernike polynomial according to a predetermined rule. The elements of the wavefront aberration change table can be obtained as a result of simulation by performing simulation using a model substantially equivalent to the projection optical system PL. As described above, the adjustment parameters include the driving amount of 6 degrees of freedom of the five movable lenses in the projection optical system PL, the wavelength of the illumination light for exposure, and the driving of Z, θx, and θy of the wafer W surface (ie, wafer stage WST). Amount.

[Imaging performance sensitivity table]
The imaging performance sensitivity table shows different exposure conditions, that is, optical conditions (exposure wavelength, maximum NA, use NA, illumination NA, aperture shape of illumination system aperture stop, illumination σ, etc.) and evaluation items. The imaging performance of the projection optical system PL obtained under each of a plurality of exposure conditions determined by a combination of the mask condition, line width, evaluation amount, pattern information, etc., and these optical conditions and evaluation items, for example, It is a database including a calculation table composed of changes per 1λ of Zernike polynomials of various aberrations (or their index values), for example, 1st to 37th terms, that is, a Zernike sensitivity table. The Zernike sensitivity table is also called Zernike Sensitivity. Therefore, a file made up of Zernike sensitivity tables under a plurality of exposure conditions is also called a “ZS file”.

  In the present embodiment, as the imaging performance for which Zernike sensitivity is calculated, the following 12 types of linear aberrations that are linear imaging performance with respect to each Zernike coefficient, that is, distortion in the X-axis direction and the Y-axis direction, 13 types of imaging performance with line width abnormal values as index values of 4 types of coma aberration, 4 types of curvature of field, 2 types of spherical aberration, and line width as nonlinear imaging performance for each Zernike coefficient It is included. Here, the line width as the nonlinear imaging performance for each Zernike coefficient includes the line width of the image of the line pattern formed on the image plane by the projection optical system PL, the line pattern extending in the vertical direction, Although there are line width differences with line patterns extending in the direction, line width differences between isolated lines and dense lines, etc., the line width of the image of the line pattern will be described below as a representative.

  The analysis apparatus 500 calculates each current imaging performance based on the calculated wavefront aberration data and the imaging performance change table, and then, the movable lens elements of the optical systems PL1 to PL3 and the exposure light IL1 and IL2. A change in imaging performance when the wavelength and the surface position of the exposed surface of the wafer W are moved is obtained. Then, the position of the movable lens element, the wavelength of the illumination light for exposure, the position of the wafer surface and the imaging performance prediction information at that time (the driving amount of the lens element, etc.) in a state where the imaging performance is expected to be the best (Adjustment parameters), residual error, and imaging performance) are output as optimization results. Here, the imaging performance is calculated in consideration of the lens element driving range acquired from the exposure apparatus 100 and the imaging performance error tolerance.

  In other words, here, due to the demand for imaging performance, when the measured wavefront aberration amount exceeds the threshold value for wavefront aberration determined based on the above-mentioned various database information, the actual imaging performance is calculated. Adjustment parameters are calculated so that the image performance approaches.

  In the present embodiment, the wavefront aberration change table with respect to the driving amount of the lens element and the imaging performance change table with respect to the wavefront aberration are included in the analysis apparatus 500. The analysis apparatus 500 may acquire the adjustment parameter of the projection optical system PL from the exposure apparatus 100 when it becomes necessary to calculate the adjustment parameter.

  Further, the analysis apparatus 500 calculates the relationship between the exposure amount, synchronization accuracy, focus, lens control error, illumination condition σ, NA of the projection optical system PL, pattern design line width, image height, and estimated line width of the pattern. A table (CD table) is shown. By referring to this CD table, the pattern line width can be estimated. As the estimated line width value of the CD table, a value actually obtained from the exposure result of the test exposure in the exposure apparatus 100 performed in advance can be adopted. Also,

[Device manufacturing processing equipment group]
The device manufacturing processing apparatus group 900 includes a CVD (Chemical Vapor Depositon) apparatus 910, an etching apparatus 920, and CMP (Chemical Mechanical Polishing) which performs a chemical mechanical polishing and planarizes the wafer. : Chemical mechanical polishing) apparatus 930 and oxidation / ion implantation apparatus 940 are provided. The CVD apparatus 910 is an apparatus that generates a thin film on a wafer, and the etching apparatus 920 is an apparatus that performs etching on a developed wafer. The CMP apparatus 930 is a polishing apparatus that flattens the surface of the wafer by chemical mechanical polishing, and the oxidation / ion implantation apparatus 940 forms an oxide film on the surface of the wafer or introduces impurities at predetermined positions on the wafer. A device for injecting. Also, a plurality of CVD apparatuses 910, etching apparatuses 920, CMP apparatuses 930, and oxidation / ion implantation apparatuses 940 are provided in the same manner as the exposure apparatus 100 and the like, and a transfer path for enabling transfer of wafers between them is provided. Is provided. In addition to this, the device manufacturing processing apparatus group 900 includes apparatuses that perform probing processing, repair processing, dicing processing, packaging processing, bonding processing, and the like.

[Management controller]
The management controller 160 centrally manages the exposure process performed by the exposure apparatus 100, and manages the C / D 110 and the wafer measurement / inspection instrument 120 in the track 200 and controls their cooperative operation. As such a controller, for example, a personal computer can be adopted. The management controller 160 receives information indicating the progress status of processing and operations, information indicating processing results, and measurement / inspection results from each apparatus through a communication network in the device manufacturing processing system 1000, and The status of the entire production line is grasped, and each apparatus is managed and controlled so that the exposure process and the like are performed appropriately.

[Host system]
A host system (hereinafter referred to as “host”) 600 manages the entire device manufacturing processing system 1000 and controls the exposure apparatus 100, the track 200, the wafer measurement / inspection instrument 120, and the device manufacturing processing apparatus group 900. It is a computer. For the host 600, for example, a personal computer can be employed. The host 600 and other devices are connected via a wired or wireless communication network so that data communication can be performed between them. By this data communication, the host 600 realizes overall control of this system.

[Device manufacturing process]
Next, a flow of a series of processes in the device manufacturing processing system 1000 will be described. FIG. 4 shows a flowchart of this process, and FIG. 5 shows a flow of data transmitted / received via the communication network in a part related to the repetitive steps in this series of device manufacturing processes. A series of processes of the device manufacturing processing system 1000 is scheduled and managed by the host 600 and the management controller 160. As described above, the wafers W are processed in units of lots, but both FIG. 4 and FIG. 5 are shown as a series of processes for one wafer W. Actually, the processing shown in FIGS. 4 and 5 is repeated, for example, in a pipeline manner for each wafer in lot units.

  As shown in FIGS. 4 and 5, first, a film is formed on the wafer W in the CVD apparatus 910 (step 201), the wafer W is transferred to the C / D 110, and the wafer W is transferred onto the wafer W in the C / D 110. A resist is applied (step 202). Next, the wafer W is transferred to the wafer measurement / inspection instrument 120, and the wafer measurement / inspection instrument 120 performs pre-measurement / inspection processing such as measurement of the surface shape of the exposed surface of the wafer W and inspection of foreign matter on the wafer W. (Step 203). The number and arrangement of the measurement shots can be arbitrary. For example, as shown in FIG. 4, the shots can be eight shots on the outer periphery of the wafer. The measurement result of the wafer measurement / inspection instrument 120 (that is, the shot flatness of the measurement shot) is sent to the exposure apparatus 100 and the analysis apparatus 500. This measurement result is used for focus control during scanning exposure in the exposure apparatus 100.

  Subsequently, the wafer W is transferred to the exposure apparatus 100, and the circuit pattern on the reticle R is transferred onto the wafer W by the exposure apparatus 100 (step 205). At this time, the exposure apparatus 100 monitors the exposure amount, synchronization accuracy, focus trace data, and illumination unevenness data during exposure of each shot area, and stores them as log data in an internal memory. As a result, the exposure amounts of the exposure light beams IL1 and IL2, the synchronization error between the wafer stage WST and the reticle stage RST, the deviation of the exposed surface of the wafer W from the best imaging plane, the Z axis of the pattern forming surface of the reticles R1 and R2 Trace data of the amount of positional deviation in the direction is acquired.

  In the exposure process of step 205, as shown in FIG. 14, the difference in surface position between the pattern formation surface of the reticle R1 in the illumination area IAR1 and the pattern formation surface of the reticle R2 in the illumination area IAR2, If there is a deviation from the best imaging plane in the exposure area IA due to the aberration of the projection optical system PL and the like, and the exposure surface of the wafer W cannot be matched with both best imaging planes, Control of the Z positions of the reticles R1 and R2 by driving the stage, focus control of the projection optical system PL, and the like are performed, and the two best imaging planes are controlled to coincide as much as possible.

  Next, the wafer W is transferred to the C / D and developed by the C / D 110 (step 207). Thereafter, post-measurement inspection processing such as measurement of the line width of the resist image by the wafer measurement / inspection instrument 120 and inspection of defects transferred onto the wafer W is performed (step 209). The measurement result (line width data) of the measurement / inspection instrument 120 is sent to the analysis apparatus 500. The analysis apparatus 500 analyzes the aberration of the projection optical system PL based on information from the exposure apparatus 100 or the measurement / inspection instrument 120 (step 211). As shown in FIG. 4, the analysis apparatus 500 issues various data transfer requests to the wafer measurement / inspection instrument 120 and the exposure apparatus 100 according to the progress of analysis and as necessary, and each apparatus according to the analysis result. Issue analysis information to Details of the analysis process in the analysis apparatus 500 and the data flow in the analysis process will be described later. Further, after the analysis apparatus 500 acquires various data, the exposure apparatus 100 may promptly delete the trace data stored therein.

  On the other hand, the wafer W is transferred from the wafer measurement / inspection instrument 120 to the etching apparatus 920, where etching is performed in the etching apparatus 920, impurity diffusion, wiring processing, film formation in the CVD apparatus 910, planarization in the CMP apparatus 930, and oxidation. -Ion implantation with the ion implantation apparatus 940 is performed as necessary (step 213). Then, the host 600 determines whether all processes are completed and all patterns are formed on the wafer W (step 215). If this determination is denied, the process returns to step 201, and if affirmed, the process proceeds to step 217. In this manner, a series of processes such as film formation / resist application to etching are repeatedly performed for the number of steps, whereby circuit patterns are stacked on the wafer W, and a semiconductor device is formed.

  After the repetition process is completed, the probing process (step 217) and the repair process (step 219) are executed in the device manufacturing processing apparatus group 900. In step 217, when a memory failure is detected, in step 219, for example, processing for replacement with a redundant circuit is performed. The analysis apparatus 500 can also send information such as the location where the detected line width abnormality has occurred to an apparatus that performs probing processing and repair processing. In the inspection apparatus (not shown), the portion where the line width abnormality has occurred on the wafer W can be excluded from the processing target for the probing process and the repair process in units of chips. Thereafter, dicing processing (step 221), packaging processing, and bonding processing (step 223) are executed, and a product chip is finally completed. Note that the post-measurement inspection process in step 209 may be performed after the etching in step 213. In this case, line width measurement is performed on the etching image on the wafer W.

[Analysis processing]
Next, the analysis process of the analysis apparatus 500 will be described in detail. FIG. 6 shows a flowchart of analysis processing in the analysis apparatus 500. As shown in FIG. 6, first, the analysis apparatus 500 performs an initial setting process (step 301). The initial setting process includes, for example, a process for creating various databases used for the analysis process of the analysis apparatus 500 described above. These creation processes are performed as described above. Exposure conditions (pattern line width in design, NA of the projection optical system PL, exposure light IL1, and exposure light IL2 may be set in the exposure apparatus 100, respectively. For each illumination σ and illumination type (deformed illumination, etc.). After this step 301 is performed, the process waits until a processing start command is received from the host 600 in step 303.

  When the processing start command is received, the analysis apparatus 500 receives the line width data at each sample point of the measurement shot from the measurement / inspection instrument 120 and stores it in a storage device (not shown) (step 305). Based on the data, it is determined whether or not the pattern line width on the wafer W is abnormal (step 307). Here, a statistical value related to the difference between the measured value of the line width in the measurement shot and the design value is calculated, and the calculated statistical value is compared with a threshold value to detect a line width abnormality. As such a statistic value, an average value of the line width may be adopted, or an index value indicating variation in the line width (for example, standard deviation, so-called 3σ that is three times the standard deviation, maximum value of line width variation, Range). Further, the sum of the average value and the index value indicating the variation (for example, the average value of the line width + 3σ) can be employed.

  The determination using this threshold is performed by comparing the statistical value of the difference between the actually measured line width and the designed line width with a predetermined threshold. Here, when it is determined that the line width is normal, the analysis apparatus 500 uses the determination result indicating that the line width is normal as analysis information (see FIG. 5). The process returns to step 303 and waits for the next processing start command. If it is determined that the line width is abnormal, the process proceeds to step 308. In step 308, the reticle whose line width is determined to be abnormal is specified. Here, it is specified whether the reticle that is the transfer source of the pattern in which the line width is detected to be abnormal is the reticle R1 or the reticle R2. Assume that pattern abnormalities corresponding to both reticles are detected.

In step 309, the analysis apparatus 500 performs focus trace data (deviation between the exposed surface of the wafer W and the best imaging plane, deviation of the surface positions of the pattern formation surfaces of the reticles R1 and R2 from the target value), synchronization accuracy trace. Data, exposure amount trace data of exposure light IL1 and IL2, surface shape data of wafer W, lens control error data in optical systems PL1 to PL3, log data such as setting values of control system parameters, and the like are collected from exposure apparatus 100 Based on these data, Z _MEAN , Z _MSD , synchronization accuracy error (moving standard deviation), exposure dose error (moving average), which are statistical values of focus control errors, are calculated, and the CD table group is referred to. Then, an estimated value of the line width corresponding to the synchronization accuracy error and the exposure amount error, Z _MEAN and Z _MSD is calculated. The analysis device 500 stores the calculated estimated line width in a storage device (not shown).

  In the next step 311, it is determined whether or not the tendency of the estimated value of the line width and the actually measured value match, and their consistency is checked. Here, if the comparison result in step 311 is that the actually measured value and the estimated value substantially match, the determination in step 311 of the analysis apparatus 500 is affirmed, and the cause of the line width abnormality is exposure. The apparatus 100 is determined to be the apparatus 100, and the process proceeds to step 313.

  In step 313, the analysis apparatus 500 determines whether each control error of exposure amount / synchronization accuracy / focus / lens error calculated in step 309 is within the standard. Here, the control errors of the exposure amount, focus, and lens error are individually determined for the exposure light IL1 and the exposure light IL2. As for the focus control error, the focus control error corresponding to the exposure light IL1 is determined by taking into account the positional deviation of the pattern forming surface of the reticle R1 with respect to the defocus of the exposed surface of the wafer W, and The focus control error corresponding to the exposure light IL2 is determined by taking into account the positional deviation of the pattern forming surface of the reticle R2 with respect to the defocus of the exposed surface. The lens error control error is individually determined by the optical systems PL1 and PL3 that guide the exposure light IL1 onto the substrate, and the optical systems PL2 and PL3 that guide the exposure light IL2 onto the substrate.

  In step 313, when the statistical value regarding the focus is out of the standard, it is determined that the focus control or the shot flatness is included as the cause of the line width abnormality. Further, when the statistical value related to the synchronization error is out of the standard, it is determined that the synchronization error is included as a cause of the line width abnormality. Further, when the statistical value related to the exposure amount is out of the standard, it is determined that the exposure amount error is included as a factor of the line width abnormality. If at least one of the statistical values is out of the standard (exposure apparatus specifications), the determination is affirmed and the process proceeds to step 315. In step 315, the analysis apparatus 500 selects the adjustment system parameter and the control system parameter related to the control error specified as the cause of the line width abnormality, and optimizes the selected parameter. The optimized parameters are sent to the exposure apparatus 100.

  In the optimization of parameters in the analysis apparatus 500, each control error is brought close to 0 by referring to the CD table group and executing a simulation with various combinations of exposure amount / synchronization accuracy / focus / lens control errors. The control system parameters may be adjusted as described above. Since the relationship between each control system parameter and each control error of exposure amount / synchronization accuracy / focus / lens is known in advance, a set value of the control system parameter for bringing each control error close to 0 can be determined.

  On the other hand, if all the statistical values of the control errors are within the standard at step 313, the determination is denied and the process returns to step 303. Here, adjustment of the projection optical system PL in steps 321 and 323 described later, that is, lens optimization may be performed.

  On the other hand, if it is determined in step 311 that the comparison results do not match, the cause of the line width abnormality other than the control error of the exposure process (film formation / resist process, pre-measurement process, development process, post-measurement process) Etc.). The determination is negative and the process proceeds to step 317. In step 317, the analysis apparatus 500 determines whether the C / D 110, the wafer measurement / inspection instrument 120, or the like is abnormal based on log data from the C / D 110, log data from the wafer measurement / inspection instrument 120, or the like. To do. For example, this determination is affirmed when there is coating unevenness in the C / D 110 that is considered to have a correlation with the line width abnormality or when the measurement state in the measurement / inspection instrument 120 is bad. If this determination is affirmative, the process proceeds to step 319, where the processing apparatus is adjusted to cause line width abnormality.

  On the other hand, referring to the log data, if there is no problem with the C / D 110 and the wafer measurement / inspection instrument 120 and the determination is negative in step 317, the process proceeds to step 321. In step 321, among the optical systems PL1 to PL3 constituting the projection optical system PL, the individual optical systems PL1 and PL2 that guide the exposure lights IL1 and IL2 to the optical system PL3 are optimized (lens optimization).

  FIG. 7 shows an example of processing in step 321. This process is started by a test exposure process request from the analysis apparatus 500 to the host 600. In response to this request, the host 600 that manages the series of lot processing shown in FIGS. 4 and 5 temporarily stops the lot processing and interrupts the processing without completely stopping the lot processing. Then, an aberration measurement processing start command is issued to the substrate processing apparatus (100, 110, 120). That is, the process shown in FIG. 7 can be regarded as an interrupt process for the lot process in FIGS. The interrupt timing can be set to an arbitrary timing, but may be interrupted when processing for the next wafer is started. In this case, the host 600 needs to temporarily save information necessary for the restoration so that the current state of the lot processing can be restored.

As shown in FIG. 7, in step 401, a test reticle on which a test pattern is formed is loaded onto reticle stage RST by a reticle exchange operation. here,
In step 308 of FIG. 6, the reticle in which an abnormality has occurred and the test reticle are exchanged. Here, it is assumed that both the reticles R1 and R2 are exchanged for the test reticle.

[Test pattern]
FIG. 8 shows an example of the test reticle RT1. The test reticle RT1 is exchanged with the reticle R1. In this test pattern, a light transmitting part PA is provided at a position corresponding to the illumination area IAR1. This translucent part is provided with an array of 33 measurement points, and an aberration measurement mark MP1 is arranged at each measurement point. The aberration measurement mark MP1 will be described later. Note that the test reticle RT2 to be exchanged with the reticle R2 has the same configuration as the test reticle RT1. The measurement points of the test reticle RT1 and the test reticle RT2 are the same.

  Returning to FIG. 7, in C / D 110, a resist is applied on a test wafer for measurement onto which a test pattern is transferred (step 403). The test wafer is transferred to the wafer measurement / inspection instrument 120 where the shot flatness is measured (step 405). Then, the test wafer is transferred to the exposure apparatus 100 where test exposure is performed (step 407). Since the exposure here is performed for measuring the aberration of the projection optical system PL, the reticle stage RST and wafer stage WST may be stationary. As the transfer position of the test pattern on the wafer W here, it is desirable to select the flattest place based on the measurement result of the shot flatness measured in advance.

  As the aberration measurement mark MP1, as shown in FIG. 9, it is possible to employ a mark in which two box-in-box marks M1 and M2 are arranged at regular intervals. The arrangement direction is not particularly limited as long as it is within the XY plane.

  On the other hand, aberration measurement marks MP2 are also arranged at 33 measurement points on the test reticle RT2 on which a test pattern exchanged with the reticle R2 is formed. As the aberration measurement mark MP2, as shown in FIG. 10, it is possible to employ a mark in which two box-in-box marks M1 and M2 are arranged at regular intervals.

  As can be understood from FIGS. 9 and 10, the aberration measurement mark MP1 at each measurement point of the test reticle RT1 and the aberration measurement mark MP2 at each measurement point of the test reticle RT2 are distances between the box-in-box marks M1 and M2. Are the same, and their arrangement is reversed. Accordingly, when double exposure is performed with the two test reticles RT1 and RT2, the two box-in-box marks M1 and M2 are transferred and formed on the test wafer so as to overlap each other.

  FIG. 11 shows an example of a result of double transfer of two box-in-box marks M1 and M2 on the wafer W. As shown in FIG. 11, by superimposing and transferring these two box-in-box marks M1 and M2, an outer thick box mark (hereinafter referred to as an outer mark) and several inner thin marks are formed on the test wafer. A box mark (hereinafter referred to as an inner mark) is transferred and formed. If the projection optical system PL has an odd function aberration represented by coma aberration as described above (an aberration in which the radial function of the Zernike polynomial is an odd function), in the transfer pattern shown in FIG. A positional shift occurs in the relative position between the outer mark and the inner mark. In the present embodiment, as will be described later, the wafer measurement / inspection instrument 120 measures the amount of positional deviation, and finally, the analysis apparatus 500 calculates the odd-function aberration component of the projection optical system PL. become.

  In addition, at each measurement point of the test reticles RT1 and RT2, two marks for measuring an even function aberration (aberration whose Zernike polynomial radial function is an even function) are provided. The two marks are the same as the aberration measurement marks MP1 and MP2 shown in FIGS. 9 and 10 when viewed in shape and arrangement, but the cross-section of the mark M2 is different. FIG. 12 shows a cross section of the mark M2 (a part of a cross section taken along line A-A ′ of FIGS. 9 and 10). As shown in the cross section of FIG. 12, this diffraction grating has a structure in which a light shielding portion, a transmission portion, and a phase digging portion are repeatedly arranged. The ratio of the width between the transmission part and the phase digging part is 1: 1 with respect to the arrangement direction of the grating, and the ratio between the light shielding part and them is n (n is a real number): 1: 1. It has become. When the digging phase angle θ satisfies 360 ° / (n + 2) + θ = 180 °, either the + 1st order diffracted light or the −1st order diffracted light disappears. Such a diffraction grating is also called PSG. In particular, PSG having a line width ratio of 2: 1: 1 and a digging phase angle of 90 ° is most suitable in terms of characteristics of a transferred resist pattern and mask design / structure. The PSG arranged on the test reticle realizes two-beam interference by the zero-order light and one primary light, and as a result, forms a standing wave inclined from the principal ray on the imaging plane. Therefore, the transfer position of the PSG image has a feature that it is laterally shifted according to the height of the exposed surface of the wafer W. Since the inclined standing wave is always linear regardless of whether there is an error or aberration in the illumination optical system, the relationship between the focus shift and the lateral shift is proportional.

  Note that the step direction of the diffraction grating mark (that is, the direction determined by the arrangement order of the convex portion and the concave portion separated by the step) is defined as the direction shown in FIG. 13 (for example, the direction of the arrow is the concave portion). ing. In such a case, if there is even function aberration in the projection optical system PL, the transfer position of the inner mark is laterally shifted from the transfer position of the outer mark. As will be described later, the wafer measurement / inspection instrument 120 measures this amount of positional deviation, and finally measures the odd-function aberration component of the projection optical system PL.

  Note that the pitch of the diffraction grating mark, the line pattern, or the exposure condition in the exposure apparatus 100 is in accordance with the pattern pitch, the line width, and the exposure condition of the reticle used in the actual process. This is desirable from the viewpoint of sensitivity of imaging performance.

  Returning to FIG. 7, the test wafer subjected to the test exposure is sent to the C / D 110 and developed (step 409). Then, the test wafer is transferred to the wafer measurement / inspection instrument 120, and the wafer measurement / inspection instrument 120 measures the amount of relative positional deviation between the outer mark and the inner mark (step 411). This measurement result is sent to the analysis device 500 and stored as measurement data relating to the wavefront aberration of the projection optical system PL in a storage device (not shown). Also, the analysis apparatus 500 makes a transfer request for various data to the exposure apparatus 100. This data includes data such as the current position of the movable lens element in the optical systems PL1 to PL3 of the projection optical system PL and the driving range of the movable lens element. Based on this measurement result, the analysis apparatus 500 creates simultaneous equations of odd function aberrations among the first to 37th terms of the Zernike polynomial, and obtains the magnitude of the coefficient of each term from the simultaneous equations. In other words, the relative displacement of the observed mark includes the effects of low-order odd-function aberration and high-order odd-function aberration, and low-order even-function aberration and high-order even function aberration. They need to be separated into values for each term of the Zernike polynomial. In order to increase the number of the simultaneous equations, a plurality of aberration measurement marks having different pitches are prepared at measurement points, or test exposure is performed under a plurality of different exposure conditions to increase the number of measurement data. There is a need. As a result, the coefficients from the first to the 37th terms of the Zernike polynomial, that is, wavefront aberration data are obtained.

  In step 413, the analysis apparatus 500, the wavefront aberration data, various data acquired from the exposure apparatus 100, the positions of the lens elements of the current optical systems PL1 to PL3, the lens element driving range, and the driving of the lens elements. The wavefront aberration change table with respect to the quantity, the imaging performance change table with respect to the wavefront aberration, and the imaging performance error allowable value are input, and the wavefront aberration data calculated from the measurement result of the wafer measurement inspector 120 is used as the result. On the basis of the optical system PL1, excluding the optical system PL3, adjustment values of the movable lens elements of the optical system PL1 and optical system PL2, exposure wavelength adjustment values, adjustment values of the attitude of the wafer stage WST, residual errors, and imaging performance after driving Are set in a storage device (not shown). Since these calculation methods are disclosed in the pamphlet of International Publication No. 2003/065428, detailed description thereof is omitted here.

  Here, the imaging performance error tolerance for the exposure light IL1 is determined according to the imaging performance required for the device pattern of the reticle R1, and the imaging performance error tolerance for the exposure light IL2 is determined by the device pattern of the reticle R2. It is determined according to the imaging performance required for. Thereby, the adjustment amount of the optical system PL1 is in accordance with the resolution required for the device pattern of the reticle R1, and the adjustment amount of the optical system PL2 is in accordance with the resolution required of the device pattern of the reticle R2. Become. That is, in this step 321, the optical system PL1 is adjusted to a level that satisfies the resolution performance required for the device pattern of the reticle R1, and the optical system PL2 is adjusted to a level that satisfies the resolution performance required for the device pattern of the reticle R2. Is preferably adjusted so that the residual aberrations of the optical systems PL1 and PL3 are substantially the same as the residual aberrations of the optical systems PL2 and PL3.

  The calculated data such as the adjustment amounts of the movable lens elements of the optical systems PL1 and PL2 of the projection optical system PL are sent to the exposure apparatus 100. The main controller 20 of the exposure apparatus 100 sets the calculated adjustment parameter. Thereby, the movable lens elements of the optical systems PL1 and PL2 of the projection optical system PL are driven.

  Returning to FIG. 6, in the next step 323, the common optical system PL3 is adjusted among the optical systems PL1 to PL3 constituting the projection optical system PL. This process is substantially the same as the process of step 321 except that the process contents of step 413 in FIG. 7 are different.

  At this time, the optical systems PL1 and PL2 are adjusted, and the aberration amount of the projection optical system PL only leaves a residual component of the adjustment. Since this residual component is very small, it is a component having almost the same size for both the exposure light IL1 and the exposure light IL2. In step 323, this residual component is reduced by adjusting the common optical system PL3. Therefore, in step 413, the analysis apparatus 500 causes the wavefront aberration data, various data acquired from the exposure apparatus 100, the positions of the lens elements of the current optical systems PL1 to PL3, the lens element driving range, and the driving of the lens elements. The wavefront aberration change table with respect to the quantity, the imaging performance change table with respect to the wavefront aberration, and the imaging performance error tolerance value are input, and based on the wavefront aberration data calculated from the measurement result of the measurement inspector 120 using them. Then, the driving amount of the movable lens element of the optical system PL3, the adjustment value of the exposure wavelength, the adjustment value of the attitude of the wafer stage WST, the residual error, and the imaging performance after driving are set in a storage device (not shown).

  The calculated data such as the adjustment amount of the movable lens element of the optical system PL3 of the projection optical system PL is sent to the exposure apparatus 100. The main controller 20 of the exposure apparatus 100 sets the calculated adjustment parameter. Thereby, the movable lens element of the optical system PL3 of the projection optical system PL is driven.

  Note that the test reticles RT1 and RT2 for measuring the wavefront aberration of the projection optical system PL are not limited to those described above. Various methods can be adopted as a method for measuring the wavefront aberration of the optical systems PL1 to PL3 of the projection optical system PL, and the present invention is not limited to this method.

  After step 323 is completed, step 321 or 323 may be performed again to further reduce the aberration of the projection optical system PL to zero. Further, the adjustment of the common optical system PL3 in step 323 may be performed prior to the adjustment of the optical systems PL1 and PL2 in step 321. If it is determined in step 321 that the aberration of the projection optical system PL satisfies the required imaging performance, step 323 is not necessarily performed.

  After executing Steps 315, 319, and 323, the analysis apparatus 500 returns to Step 303 and waits again until a processing start command is received. The host 600 resumes the interrupted lot processing.

  Note that the analysis processing in the analysis apparatus 500 described above is independent of the processing in other apparatuses, and hardly affects the throughput of device manufacturing. The lens optimization process in steps 321 and 323 is also performed as an interrupt process for the normal lot process. The interrupt process and the test exposure in the lens adjustment can be performed as a series of process wafer processes by simply exchanging the reticle. Since it can be performed in the same manner, it is not necessary to completely stop the lot processing. Therefore, according to this process, the projection optical system PL can be quickly adjusted.

  It should be noted that process conditions such as resist processing, development processing, and etching processing in the C / D 110 other than the exposure apparatus 100 may be added as the pattern line width estimation conditions in the CD table.

  In this embodiment, when measuring the aberration of the projection optical system PL, both the reticles R1 and R2 are exchanged with the test reticles RT1 and RT2. However, only the reticle specified at step 308 is exchanged with the test reticle. Thus, aberration measurement may be performed. In this case, in step 407 of FIG. 7, the test exposure is performed by irradiating only the exposure light that has been replaced with the test reticle. In this case, after the test pattern on the test reticle is transferred once to the test wafer, the wafer stage WST is shifted by the distance between the two marks M1 and M2 (see FIGS. 9 and 10) and transferred once more. I do. Then, the two marks M1 and M2 are transferred and formed on the test wafer so as to overlap each other, and aberration measurement is possible as in the present embodiment.

  In this embodiment, the line width is measured only for measurement shots selected in advance for each wafer. However, the frequency of line width measurement may be increased or decreased according to the frequency of occurrence of abnormality. For example, when the number of measurement shots in which line width abnormality is confirmed increases, the number of measurement shots in the wafer W can be increased, and when the number of measurement shots in which line width abnormality is confirmed decreases. It is also possible to reduce the number of measurement shots. Further, the measurement of the line width abnormality may not be performed on all the wafers, and may be performed every several sheets. For example, if no abnormality in the line width occurs continuously for a predetermined number of sheets, the line width measurement is performed every three wafers. If no abnormality in the line width continues after that, the number of line width measurements is set to the wafer 10. Only the wafer W at the head of the lot may be measured finally. Of course, when a new line width abnormality occurs, it is of course necessary to increase the measurement frequency of the line width. Also, based on the past process operation history, for wafers with a high probability of pattern abnormalities (for example, wafers at the beginning of a lot when pattern abnormalities are likely to occur at the wafer at the beginning of a lot) Line width abnormality detection may be performed.

  Further, in the present embodiment, when the line width abnormality of the pattern is detected during the lot processing, the aberration of the projection optical system PL is measured and the projection optical system PL is adjusted. It fluctuates due to changes over time, atmospheric pressure fluctuations, irradiation heat of exposure light IL1 and IL2, etc., and changes when the illumination conditions and the pattern on the reticle are changed. The aberration measurement shown in FIG. 7 may be performed at a timing (for example, every month) in consideration of the aberration fluctuation factor. Further, the processing of FIG. 7 may be performed when adjusting the aberration of the projection optical system when the apparatus is started up before the exposure apparatus 100 is operated.

  As described above in detail, according to the present embodiment, the optical characteristic information of the exposure apparatus 100 that includes the optical system PL3 that guides the exposure light IL1 and the exposure light IL2 and that can perform multiple exposure using both the exposure lights IL1 and IL2. Get the measurement test result. This measurement / inspection result is useful information for adjusting the optical characteristics of the exposure apparatus 100.

  The exposure apparatus 100 according to this embodiment is an exposure apparatus that performs multiple exposure of the wafer W with the exposure light IL1 and the exposure light IL2. Such an exposure apparatus 100 is advantageous in throughput because it can expose two patterns in a multiple manner at a time. Note that this multiple exposure does not have to be performed on all shot areas on the wafer W, and even if it is performed on at least a part, the exposure time is shorter than when double exposure is performed non-simultaneously. This is advantageous for throughput.

  In the present embodiment, the optical characteristic information of the exposure apparatus 100 is generated based on the result of measuring and inspecting the wafer W exposed by the exposure apparatus 100. In this way, accurate optical characteristic information of the exposure apparatus 100 can be acquired based on the actual exposure result.

  Further, according to the present embodiment, based on the result of measuring and inspecting the wafer W exposed by the exposure apparatus 100, the optical characteristic information of the exposure apparatus 100 is generated by subtracting components other than the projection optical system PL. In this way, it is possible to acquire accurate optical characteristic information in which components caused by components other than the projection optical system PL are removed from the actual exposure result for the wafer W.

  The exposure apparatus 100 according to the present embodiment includes a wafer stage WST that holds the wafer W and controls the position of the wafer W. Therefore, the normal exposure result includes components resulting from the control of the wafer W stage. In the present embodiment, since the test exposure is performed in a state where the wafer stage WST and the reticle stage RST are stationary in Step 407 of FIG. 7, the components of the projection optical system PL can be accurately measured without entering the exposure result. Optical characteristic information can be acquired.

  In addition, the exposure apparatus 100 according to the present embodiment includes a reticle stage RST (a substage that holds the reticle R1) that controls the position of the reticle R1, and a reticle stage RST (a substage that holds the reticle R2) that controls the position of the reticle R2. Stage). The optical system PL3 guides the exposure light IL1 through the first pattern and the exposure light IL2 through the second pattern onto the wafer W. Therefore, the normal exposure result includes components resulting from the control of the two substages. In the present embodiment, as described above, in step 407 of FIG. 7, the test exposure is performed with the substage still, so that the accurate optical of the projection optical system PL can be obtained with the component not included in the exposure result. Characteristic information can be acquired.

  Further, the exposure apparatus 100 according to the present embodiment includes an exposure amount control device EC1 that controls the exposure amount of the exposure light IL1, and an exposure amount control device EC2 that controls the exposure amount of the exposure light IL2. Accordingly, the normal exposure result also includes components resulting from the control of the exposure control device EC1 or the exposure control device EC2. In the present embodiment, as described above, in step 407 in FIG. 7, the test exposure is performed in a state where the substage is also stationary and the component does not enter the exposure result. Therefore, the component is averaged and the exposure result is obtained. Thus, accurate optical characteristic information of the projection optical system PL can be acquired.

  In the present embodiment, the first optical characteristic information related to the irradiation of the exposure light IL1 (that is, the optical characteristic information of the optical systems PL1 and PL3) and the second optical characteristic information related to the irradiation of the exposure light IL2 (that is, the optical systems PL2 and PL3). Optical characteristic information).

  According to the present embodiment, the first optical characteristic information relating to the irradiation of the exposure light IL1 is obtained based on the result of measuring and inspecting the exposed test wafer by exposing the test wafer almost simultaneously with the exposure light IL1 and the exposure light IL2. In addition, the second optical characteristic information related to the irradiation of the exposure light IL2 is obtained separately from the first optical characteristic information.

  That is, according to the present embodiment, the first and second optical characteristic information includes the exposure light via the box-in-box mark M2 applied to the mark formed on the test wafer by the exposure light via the box-in-box mark M1. Measurement / inspection is performed using a measurement / inspection mark formed on the test wafer by irradiation.

  Then, when the exposure light IL1 is irradiated onto the test wafer via the test reticle RT1 having both the box-in-box mark M1 and the box-in-box mark M2, the box-in-box M1 and the box-in-box mark M2 are substantially simultaneously irradiated. The exposure light IL2 is irradiated onto the test wafer through the test reticle RT2 having both.

  Then, the outer mark formed on the test wafer with the exposure light IL1 through the box-in-box mark M1 is irradiated with the exposure light IL2 through the box-in-box mark M2, and the inner mark formed on the test wafer is used. Then, the optical characteristic information regarding the optical system PL2 is obtained, and the outer light mark formed on the test wafer with the exposure light IL2 through the box-in-box mark M1 is irradiated with the exposure light IL1 through the box-in-box mark M2. Using the formed inner mark, optical characteristic information regarding the optical system PL1 is obtained.

  In this way, it is possible to obtain the optical characteristic information of the optical system PL1 and the optical characteristic information of the optical system PL2 at a time, which is advantageous for throughput and in a state measured in actual process wafer exposure. Since the aberration of the projection optical system PL can be measured, it is possible to adjust the aberration of the projection optical system PL that matches the actual imaging characteristics.

  However, the reticle R1 is replaced with the test reticle RT1, the exposure light IL2 is not irradiated, the test wafer is exposed only with the exposure light IL1, and the exposure light is based on the result of measurement and inspection of the test wafer exposed with the exposure light IL1. The optical characteristics of the optical systems PL1 and PL3 related to the irradiation of IL1 are obtained, the reticle R2 and the test reticle RT2 are exchanged, the exposure light IL1 is not irradiated, the test wafer is exposed only with the exposure light IL2, and the exposure light IL2 is exposed. Based on the result of measuring and inspecting the test wafer, the optical characteristics of the optical systems PL2 and PL3 related to the irradiation of the exposure light IL2 may be obtained.

  Further, according to the present embodiment, the optical characteristics of the exposure apparatus 100 are measured and inspected by the wafer measurement / inspection instrument 120 provided separately from the exposure apparatus 100. In this way, the exposure process and the measurement inspection process can be performed in parallel, which is advantageous for throughput.

  In addition, according to the present embodiment, measurement and inspection are performed with a wafer measurement and inspection device 120 provided separately from the exposure apparatus 100, and the measurement and inspection results with the wafer measurement and inspection instrument 120 are transmitted to the exposure apparatus 100 via a communication unit. . As described above, the cooperative operation between the exposure apparatus and the measurement / inspection instrument 120 enables the optical characteristics of the exposure apparatus to be adjusted efficiently and appropriately.

  The wafer measurement / inspection instrument 120 is a measurement / inspection apparatus characterized by measuring and inspecting optical characteristic information of the exposure apparatus 100 using the measurement / inspection method according to the present embodiment. By using this wafer measurement / inspection instrument 120, the measurement / inspection result of the optical characteristic information of the projection optical system PL of the exposure apparatus 100 capable of multiple exposure using the exposure light IL1 and the exposure light IL2 is obtained, and based on the result. The projection optical system PL can be adjusted.

  The exposure apparatus 100 according to the present embodiment guides the optical system PL1 that guides the exposure light IL1, the optical system PL2 that guides the exposure light IL2, the exposure light IL1 guided by the optical system PL1 onto the wafer W, and the optical system. The exposure apparatus includes an optical system PL3 that guides the exposure light IL2 guided by PL2 onto the wafer W. The exposure apparatus exposes the wafer W with the exposure light IL1 and the exposure light IL2. Then, based on the optical characteristic information detected from the measurement / inspection result of the measurement / inspection process of the wafer measurement / inspection instrument 120, the exposure apparatus 100 performs the first optical characteristic relating to the irradiation of the exposure light IL1 (the comprehensiveness of the optical systems PL1 and PL3). The optical exposure is performed while controlling at least one of the second optical characteristics related to the irradiation of the exposure light IL2 (the overall optical characteristics of the optical systems PL2 and PL3).

  According to the exposure apparatus of the present embodiment, at least one of the first optical characteristic related to the irradiation of the exposure light IL1 and the second optical characteristic related to the irradiation of the exposure light IL2 based on the optical characteristic information detected by the measurement inspection process. Since exposure is performed while controlling the above, multiple exposure with high accuracy and high throughput becomes possible.

  From another point of view, this embodiment can be regarded as a device manufacturing processing apparatus that manufactures a device using the exposure apparatus 100. In such a case, multiple exposure with high accuracy and high throughput using the exposure apparatus 100 is possible, and the yield of device production can be improved.

  In the present embodiment, the analysis apparatus 500 and the wafer measurement / inspection instrument 120 are individually provided, but both may be integrated. That is, the wafer measurement / inspection instrument 120 may have the function of the analysis apparatus 500.

  In the present embodiment, the exposure area on the exposed surface of the wafer W of the exposure light IL1 and the exposure light IL2 is defined as the exposure area IA, and the exposure areas are overlapped. However, the irradiation areas of the exposure light IL1 and the exposure light IL2 are It does not matter if they are separate.

  In the present embodiment, a transmissive reticle is used, but a reflective reticle may be used. Further, in the present embodiment, two reticles are used at the same time, but one reticle on which two patterns are formed may be used.

  In addition, the exposure apparatus 100 according to the present embodiment transfers the device pattern onto the wafer W by simultaneous double exposure of the pattern. However, the exposure apparatus 100 according to the present embodiment is also applicable to an exposure apparatus capable of simultaneously performing triple exposure and quadruple exposure. Of course, the invention can be applied.

  The exposure apparatus 100 according to the present embodiment uses an exposure apparatus that performs so-called multiple exposure that exposes a plurality of patterns simultaneously. However, the present invention is also applicable to an exposure apparatus that performs multiple exposure by exchanging reticles R1 and R2 as needed. Of course, can be adopted.

  In the above embodiment, the vacuum chucking type reticle holder RH is used. However, the present invention can also be applied to an electrostatic chucking type or other type of reticle holder.

  Further, as disclosed in JP-A-11-135400 and JP-A-2000-164504, a measurement stage equipped with a wafer stage for holding the wafer W, a reference member on which a reference mark is formed, and various photoelectric sensors. The present invention can also be applied to an exposure apparatus including the above.

  In the above embodiment, the step-and-scan type projection exposure apparatus has been described. However, the present invention is not limited to these projection exposure apparatuses, and other step-and-repeat type and proximity type exposure apparatuses are also available. Needless to say, the present invention can also be applied to an exposure apparatus. The present invention can also be suitably applied to a step-and-stitch reduction projection exposure apparatus that combines a shot area and a shot area. As represented by this, the various apparatuses are not limited to those types.

  Further, for example, the present invention can be applied to a twin stage type exposure apparatus having two wafer stages as disclosed in International Publication Nos. WO98 / 24115 and WO98 / 40791. Of course, the present invention can also be applied to an exposure apparatus using a liquid immersion method disclosed in, for example, International Publication WO99 / 49504. In this case, the present invention provides an exposed surface of a substrate to be exposed as disclosed in JP-A-6-124873, JP-A-10-303114, US Pat. No. 5,825,043 and the like. The present invention can also be applied to an immersion exposure apparatus that performs exposure in a state where the entirety is immersed in a liquid.

  The present invention is not limited to a semiconductor manufacturing process, and can be applied to a manufacturing process of a display including a liquid crystal display element. In addition, the present invention is applied to all device manufacturing processes in addition to a process of transferring a device pattern onto a glass plate, a manufacturing process of a thin film magnetic head, a manufacturing process of an image pickup device (CCD, etc.), a micromachine, an organic EL, and a DNA chip. Of course, can be applied.

  In the above embodiment, the analysis apparatus 500 is a PC, for example. That is, the analysis processing in the analysis apparatus 500 is realized by executing an analysis program on a PC. As described above, this analysis program may be installable on the PC via a medium, or may be downloadable to the PC via the Internet or the like. Of course, the analysis apparatus 500 may be configured by hardware. Further, the function of the analysis apparatus 500 may be included in the wafer measurement / inspection instrument 120, the exposure apparatus 110, the C / D 110, the host 600, or the like.

  As described above, the measurement / inspection method, measurement / inspection apparatus, exposure apparatus, and device manufacturing processing apparatus of the present invention are suitable for manufacturing a device.

It is a figure which shows schematic structure of the device manufacturing system which concerns on one Embodiment of this invention. It is a figure which shows schematic structure of exposure apparatus. It is a block diagram of the control system of exposure apparatus. 5 is a flowchart showing a flow of a series of processes in the device manufacturing processing system 1000. It is a figure which shows the flow of a process. It is a flowchart of an analysis process. It is a figure which shows the flow of lens optimization. It is a figure which shows an example of a test reticle. It is a figure which shows an example (the 1) of the mark for aberration measurement. It is a figure which shows an example (the 2) of an aberration measurement mark. It is a figure which shows an example of the transcription | transfer result of the mark for aberration measurement. It is a figure showing the section of the mark for aberration measurement. It is a figure which shows the level | step difference direction of the diffraction grating of the measurement mark of even function aberration. It is a figure which shows typically the relationship between the pattern formation surface of a reticle, the to-be-exposed surface of a wafer, and the best image formation surface of a pattern image.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Illumination system, 20 ... Main control apparatus, 100 ... Exposure apparatus, 110 ... C / D, 160 ... Management controller, 200 ... Track, 500 ... Analysis apparatus, 600 ... Host system, 900 ... Device manufacturing processing apparatus group, 1000 ... Device manufacturing processing system, EC1, EC2 ... Exposure amount control system, IA ... Exposure area, IAR1, IAR2 ... Illumination area, IL1, IL2 ... Exposure light, LC ... Lens control system, MP1 ... Aberration measurement mark, PL ... Projection optics System, PL1, PL2, PL3 ... Optical system, R1, R2 ... Reticle, RH ... Reticle holder, RST ... Reticle stage, RT1, RT2 ... Test reticle, SA ... Shading zone, SC ... Stage control system, W ... Wafer, WST ... wafer stage.

Claims (21)

  A third optical system for guiding both the first exposure light guided by the first optical system and the second exposure light guided by the second optical system onto the substrate; A measurement inspection method for measuring and inspecting optical characteristic information of an exposure apparatus that exposes with exposure light.   The measurement and inspection method, wherein the exposure apparatus performs multiple exposure of at least a part of the substrate with the first exposure light and the second exposure light.   The measurement / inspection method according to claim 1, wherein the optical characteristic information is generated based on a result of measurement / inspection of the substrate exposed by the exposure apparatus.   The measurement / inspection method according to claim 3, wherein the optical characteristic information is generated by subtracting components originating from components other than the optical system based on a result of measurement / inspection of the substrate exposed by the exposure apparatus. The exposure apparatus includes a substrate stage that holds the substrate and controls the position of the substrate,
The measurement / inspection method according to claim 4, wherein the component caused by other than the optical system is a component caused by control of the substrate stage. The exposure apparatus holds a first pattern and controls a position of the first pattern;
A second holding device for controlling the position of the second pattern holding the second pattern,
The third optical system guides the first exposure light through the first pattern and the second exposure light through the second pattern onto the substrate;
The measurement / inspection method according to claim 4, wherein the component caused by other than the optical system is a component caused by control of the first holding device or the second holding device. The exposure apparatus includes a first exposure amount control device that controls an exposure amount of the first exposure light, and a second exposure amount control device that controls an exposure amount of the second exposure light,
7. The component according to claim 4, wherein the component other than the optical system is a component caused by control of the first exposure amount control device or the second exposure amount control device. Measurement inspection method.   4. The first optical characteristic information related to the irradiation of the first exposure light is obtained separately from the second optical characteristic information related to the irradiation of the second exposure light. 5. Measurement inspection method. Exposing the substrate substantially simultaneously with the first exposure light and the second exposure light;
Based on the result of measuring and inspecting the exposed substrate, the first optical characteristic information relating to the irradiation of the first exposure light is obtained, and the second optical characteristic information relating to the irradiation of the second exposure light is obtained as the first optical characteristic. The measurement / inspection method according to claim 1, wherein the measurement / inspection method is obtained separately from the information. The first and second optical characteristic information is formed on the substrate by irradiating the first mark formed on the substrate with the exposure light through the first mark pattern and the exposure light through the second mark pattern. Is measured and inspected using the measurement inspection mark
The first mark pattern and the second mark pattern are substantially simultaneously irradiated with the first exposure light on the substrate through a first pattern member having both the first mark pattern and the second mark pattern. And irradiating the second exposure light on the substrate through a second pattern member having both of
A measurement formed on the substrate by irradiating the first mark formed on the substrate with the first exposure light through the first mark pattern with the second exposure light through the second mark pattern. Using the inspection mark, obtaining optical characteristic information about the first optical system,
A measurement inspection mark formed by irradiating the first mark formed on the substrate with the second exposure light through the first mark pattern with the first exposure light through the second mark pattern. The method for measuring and inspecting according to claim 9, wherein optical characteristic information relating to the second optical system is used. Based on the result of measuring and inspecting the substrate exposed with the first exposure light, regardless of the second exposure light, and with the first exposure light, the first optical characteristics relating to the irradiation of the first exposure light are Asking
A second optical characteristic related to irradiation of the second exposure light based on a result of measuring and inspecting the substrate exposed with the second exposure light and exposing the substrate with the second exposure light regardless of the first exposure light. The measurement / inspection method according to claim 1 or 2, wherein:   The measurement / inspection method according to claim 1, wherein the optical characteristic of the exposure apparatus is measured and inspected by a measurement / inspection apparatus provided separately from the exposure apparatus. Measuring and inspecting with a measurement and inspection apparatus provided separately from the exposure apparatus,
The measurement / inspection method according to claim 12, wherein a result of measurement / inspection performed by the measurement / inspection apparatus is transmitted to the exposure apparatus via a communication unit.   A measurement / inspection apparatus for measuring and inspecting optical characteristic information of the exposure apparatus by the measurement / inspection method according to claim 1. A first optical system for guiding first exposure light;
A second optical system for guiding the second exposure light;
A third optical system that guides the first exposure light guided by the first optical system onto the substrate and guides the second exposure light guided by the second optical system onto the substrate; An exposure apparatus that exposes a substrate with the first exposure light and the second exposure light,
Control for controlling at least one of the first optical characteristic related to the irradiation of the first exposure light and the second optical characteristic related to the irradiation of the second exposure light based on the optical characteristic information detected by the predetermined measurement inspection process. An exposure apparatus comprising the apparatus.   The exposure apparatus according to claim 15, wherein at least a part of the substrate is subjected to multiple exposure with the first exposure light and the second exposure light.   The exposure apparatus according to claim 15 or 16, wherein the optical characteristic information detected by the predetermined measurement / inspection process is information generated based on a result of measurement / inspection of the exposed substrate. The controller is
The first optical characteristic is controlled based on the first optical characteristic information obtained in the measurement inspection process, and based on the second optical characteristic information obtained separately from the first optical characteristic information, the The exposure apparatus according to any one of claims 15 to 17, wherein the second optical characteristic is controlled. Exposing the substrate substantially simultaneously with the first exposure light and the second exposure light;
The control device controls the first optical characteristic based on first optical characteristic information obtained based on a result of measuring and inspecting the exposed substrate, and is obtained separately from the first optical characteristic information. The exposure apparatus according to claim 18, wherein the second optical characteristic is controlled based on second optical characteristic information. Exposing the substrate with the first exposure light regardless of the second exposure light;
The control device controls the first optical characteristic based on first optical characteristic information obtained based on a result of measuring and inspecting the substrate exposed with the first exposure light;
Exposing the substrate with the second exposure light regardless of the first exposure light;
The said control apparatus controls a 2nd optical characteristic based on the 2nd optical characteristic information calculated | required based on the result of having measured and inspected the board | substrate exposed with the said 2nd exposure light, It is characterized by the above-mentioned. Exposure device.   A device manufacturing processing apparatus, comprising the exposure apparatus according to any one of claims 15 to 20, and manufacturing a device.

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