JP5865980B2 - Charged particle beam drawing apparatus and charged particle beam drawing method - Google Patents

Description

  The present invention relates to a charged particle beam writing apparatus and a charged particle beam writing method. For example, a pattern is drawn on a mask substrate using an electron beam to manufacture a mask used for extreme ultraviolet (EUV) exposure. The present invention relates to a drawing apparatus and method.

  Lithography technology, which is responsible for the progress of miniaturization of semiconductor devices, is an extremely important process for generating a pattern among semiconductor manufacturing processes. In recent years, with the high integration of LSI, circuit line widths required for semiconductor devices have been reduced year by year. In order to form a desired circuit pattern on these semiconductor devices, a highly accurate original pattern (also referred to as a reticle or a mask) is required. Here, the electron beam (electron beam) drawing technique has an essentially excellent resolution, and is used for producing a high-precision original pattern.

  FIG. 10 is a conceptual diagram for explaining the operation of the variable shaping type electron beam drawing apparatus. The variable shaped electron beam (EB) drawing apparatus operates as follows. In the first aperture 410, a rectangular opening for forming the electron beam 330, for example, a rectangular opening 411 is formed. Further, the second aperture 420 is formed with a variable shaping opening 421 for shaping the electron beam 330 having passed through the opening 411 of the first aperture 410 into a desired rectangular shape. The electron beam 330 irradiated from the charged particle source 430 and passed through the opening 411 of the first aperture 410 is deflected by the deflector, passes through a part of the variable shaping opening 421 of the second aperture 420, and passes through a predetermined range. The sample 340 mounted on a stage that continuously moves in one direction (for example, the X direction) is irradiated. That is, the drawing area of the sample 340 mounted on the stage in which the rectangular shape that can pass through both the opening 411 of the first aperture 410 and the variable shaping opening 421 of the second aperture 420 is continuously moved in the X direction. Drawn on. A method of creating an arbitrary shape by passing both the opening 411 of the first aperture 410 and the variable shaping opening 421 of the second aperture 420 is referred to as a variable shaping method.

  Here, with the miniaturization of semiconductor devices, it has been studied to make the exposure wavelength itself shorter than before. The light of 157 nm has been abandoned due to the limitation of the lens material for reduced transfer. Therefore, it is EUV light having a wavelength of 13.4 nm that is considered to be most likely at the present time. Since EUV light is transmitted and absorbed by many objects with light divided into a soft X-ray region, it is no longer possible to form a projection optical system. Therefore, a reflection optical system has been proposed for an exposure method using EUV light. As described above, in the EUV lithography, a reflection optical system including a multilayer mirror that reflects EUV light is used. An EUV mask for EUV exposure is interposed as a part of the optical system. Therefore, similarly, a reflective mask in which a multilayer film is formed on a substrate is used. A multilayer film in which molybdenum (Mo) and silicon (Si) layers are alternately stacked is used.

  Here, when the regularity of the thickness of each of the stacked layers is lost, the phase of the reflected light is shifted. As a result, the wafer is exposed as a phase defect. Therefore, it is desirable that the defect on the substrate surface of the multilayer film is zero (0). Furthermore, it is desirable to prevent foreign substances that cause defects during the lamination of the multilayer film. Furthermore, since the EUV mask bears a part of the reflection optical system, the unevenness on the surface causes the reflection surface to shift. As a result, the position of the pattern transferred onto the wafer during exposure is shifted. Therefore, high-precision flatness of the substrate itself is required.

  However, it is difficult to completely eliminate the defects of the substrate, and if the manufactured masks are completely inspected and only those having zero defects or satisfying the specifications are selected, the substrate becomes very expensive. .

  Therefore, the phase defect on the multilayer mask is not transferred by moving the absorber pattern so that the defect is not transferred by the exposure process so that the phase defect is included in the region of the absorber pattern. The technique of doing is disclosed (for example, refer patent document 1).

  The position of the defect is specified in advance by a foreign substance inspection apparatus for mask blanks (substrate), and it is necessary to reflect the pattern data so that the pattern layout is shifted according to the position of the defect. Then, it is necessary to reliably draw such mask blanks with shifted pattern data. However, the drawing apparatus can arrange a plurality of mask blanks and can register a plurality of drawing processes. Therefore, there is a problem that the drawing order and the mask blank to be used may be mistaken.

JP 2004-193269 A

  As described above, it is necessary to reliably draw a substrate in which a defect exists at such a defect position with drawing data in which the pattern layout is shifted based on the defect position. However, there is a problem that the drawing order and the mask blank to be used may be mistaken. Furthermore, there is a problem that there is a possibility that the pattern data that should have shifted the pattern layout may not include the defect in the region of the absorber pattern. Conventionally, a sufficient technique for solving such a problem has not been established.

  Therefore, the present invention has an object to provide an apparatus and a method for overcoming such a problem, and capable of reliably drawing a substrate having such a defect with drawing data in which the defect is included in the region of the absorber pattern. To do.

A charged particle beam drawing apparatus according to one embodiment of the present invention includes:
A reading unit that reads an identifier from a substrate on which an absorber film that absorbs extreme ultraviolet (EUV) light is formed and an optically readable identifier (ID) is formed;
A storage unit for storing defect position information indicating the position of a defect on the substrate, defect size information indicating the size of the defect, and pattern data for drawing, which are associated with the identifier;
Input partial pattern data, defect position information, and defect size information for at least the area including defects in the pattern data, and configure the pattern layout so that the defects are located in the area where the absorber film remains after patterning A verification unit that verifies whether or not
A drawing unit that draws a pattern on the substrate using a charged particle beam based on pattern data in which a pattern layout is configured such that a defect is located in a region where an absorber film remains after patterning;
It is provided with.

  With this configuration, it is possible to confirm that the defect is included in the region of the absorber pattern before drawing the pattern on the substrate. Then, a pattern can be drawn using the confirmed drawing data and the substrate.

In addition, as a result of verification, when a defect is not located in a region where the absorber film remains after patterning, an offset value calculation unit that calculates an offset value for correcting the defect so that the defect is located in a region where the absorber film remains after patterning Further comprising
It is preferable that the drawing unit draw a pattern at a position corrected by the offset value based on pattern data in which the pattern layout was not configured so that the defect is located in the region where the absorber film remains after patterning. .

Also, a dose map creation unit that creates a dose map for irradiating the substrate with a charged particle beam,
As a result of the verification, when a defect is not located in the region where the absorber film remains after patterning, a detection unit that detects the region where the absorber film remains after patterning using an irradiation map,
Further comprising
The offset value calculation unit calculates an offset value for correcting the defect so that the defect is located in the detected region ,
In the irradiation map, the drawing region is virtually divided into grid-like meshes, the irradiation amount for each mesh is defined, and a group of meshes having a non-zero irradiation amount whose area is larger than the defect size is the absorber film. Is preferably detected as a remaining region .

Alternatively, it further includes a detection unit that detects a region where the absorber film remains after patterning using the partial pattern data,
It is preferable that the offset value calculation unit calculates an offset value for correcting the defect so that the defect is located in the detected area.

The charged particle beam drawing method of one embodiment of the present invention includes:
A step of reading an identifier from a substrate on which an absorber film that absorbs extreme ultra violet (EUV) light is formed and an optically readable identifier (ID) is formed;
From a storage device that stores defect position information indicating the position of a defect on the substrate, defect size information indicating the size of the defect, and pattern data for drawing, which are associated with the identifier, at least a defect of the pattern data is present. Reading out partial pattern data, defect position information, and defect size information for the included region, and verifying whether the pattern layout is configured so that the defect is located in a region where the body film remains after patterning; ,
A step of drawing a pattern on a substrate using a charged particle beam based on pattern data in which a pattern layout is configured such that a defect is located in a region where an absorber film remains after patterning;
Creating a dose map for irradiating the substrate with a charged particle beam;
As a result of verification, when the defect is not located in a region where the absorber film remains after patterning, a step of detecting a region where the absorber film remains after patterning using the dose map;
As a result of verification, when the defect is not located in a region where the absorber film remains after patterning, a step of calculating an offset value for correcting the defect so that the defect is located in a region where the absorber film remains after patterning; ,
With
Calculating an offset value for correcting the defect so that the defect is located in the detected area;
In the irradiation map, the drawing region is virtually divided into grid-like meshes, the irradiation amount for each mesh is defined, and a group of meshes having a non-zero irradiation amount whose area is larger than the defect size is the absorber film. Is detected as a remaining region .

  According to the present invention, a substrate on which such a defect exists can be reliably drawn with pattern data in which the defect is included in the region of the absorber pattern. Therefore, when the wafer is exposed with the manufactured mask, phase defects existing in the mask can be prevented from being transferred onto the wafer.

1 is a conceptual diagram illustrating a configuration of a drawing apparatus according to Embodiment 1. FIG. It is a top surface conceptual diagram which shows an example of the EUV mask in which the defect in Embodiment 1 exists. FIG. 3 is a conceptual cross-sectional view showing a cross section of the EUV mask of FIG. 2. FIG. 3 is a conceptual diagram illustrating an example when a pattern is drawn on a substrate having defects in the first embodiment. 3 is a conceptual cross-sectional view of a substrate to be drawn in the first embodiment. FIG. FIG. 4 is a flowchart showing main steps of the drawing method according to Embodiment 1. FIG. 3 is a conceptual diagram illustrating an example of a substrate transport path in the drawing apparatus according to the first embodiment. 3 is a conceptual diagram illustrating an example of a defect position after shifting in the first embodiment. FIG. FIG. 3 is a diagram showing an example of a dose map in the first embodiment. It is a conceptual diagram for demonstrating operation | movement of a variable shaping type | mold electron beam drawing apparatus.

  Hereinafter, in the embodiment, a configuration using an electron beam will be described as an example of a charged particle beam. However, the charged particle beam is not limited to an electron beam, and a beam using charged particles such as an ion beam may be used.

Embodiment 1 FIG.
FIG. 1 is a conceptual diagram illustrating a configuration of a drawing apparatus according to the first embodiment. In FIG. 1, a drawing apparatus 100 is an example of a charged particle beam drawing apparatus. Here, in particular, an example of a variable shaping type electron beam drawing apparatus is shown. The drawing apparatus 100 includes a drawing unit 150, a control unit 160, a loading / unloading port (I / F) 120, a load lock (L / L) chamber 130, a robot (R) chamber 140, an alignment (ALN) chamber 146, and a vacuum pump 170. It has. The drawing apparatus 100 draws a desired pattern on the substrate 101 using the electron beam 200. Examples of the substrate 101 to be drawn include mask blanks of a mask substrate that transfers a pattern to a semiconductor wafer using EUV light.

  The drawing unit 150 includes an electron column 102 and a drawing chamber 103. In the electron column 102, an electron gun 201, an illumination lens 202, a first aperture 203, a projection lens 204, a deflector 205, a second aperture 206, an objective lens 207, a deflector 208, and a detector 212 are arranged. Has been. In the drawing chamber 103, an XY stage 105 is arranged so as to be movable. When drawing a pattern, a plurality of support pins 106 (an example of a holding unit) are arranged on the XY stage 105 so as to be movable up and down, and the substrate 101 is placed on the support pins 106. In addition, a transfer robot 122 that transfers the substrate 101 is disposed in the carry-in / out opening 120. In the robot chamber 140, a transfer robot 142 for transferring the substrate 101 is disposed. Further, a reading device 121 capable of optically reading an ID (identifier) formed on the substrate 101 is disposed at the carry-in / out port 120.

  The control unit 160 includes a computer unit 110, a control circuit 162, a detection circuit 164, and storage devices 108 and 109 such as a magnetic disk device. The computer unit 110, the control circuit 162, the detection circuit 164, and the storage devices 108 and 109 such as a magnetic disk device are connected to each other via a bus (not shown).

  The control circuit 162 is controlled by the drawing data processing unit 76, and the control circuit 162 controls and drives each device in the drawing unit 150, the loading / unloading port 120, the L / L chamber 130, the robot chamber 140, and the alignment chamber 146. The ID read by the reading device 121 is output to the computer unit 110. Further, the data detected by the detector 212 is output to the computer unit 110.

  In the control computer unit 110, an ID acquisition unit 60, a defect coordinate / size acquisition unit 62, a partial pattern data / shift amount and direction acquisition unit 64, a verification unit 66, a detection unit 68, and an ALN-mark (alignment mark) position acquisition A unit 70, an offset value calculation unit 72, an offset processing unit 74, a drawing data processing unit, and a memory 78 are arranged. ID acquisition unit 60, defect coordinate / size acquisition unit 62, partial pattern data / shift amount and direction acquisition unit 64, verification unit 66, detection unit 68, ALN-mark position acquisition unit 70, offset value calculation unit 72, offset processing unit 74 and each function of the drawing data processing unit may be configured by software such as a program for causing a computer to execute. Or you may comprise by hardware, such as an electric equipment or an electronic device. Alternatively, a combination of software and hardware may be used. Alternatively, a combination of firmware and hardware may be used. ID acquisition unit 60, defect coordinate / size acquisition unit 62, partial pattern data / shift amount and direction acquisition unit 64, verification unit 66, detection unit 68, ALN-mark position acquisition unit 70, offset value calculation unit 72, offset processing unit 74, and input information and arithmetic processing information processed by each function of the drawing data processing unit are stored in the memory 78 each time.

  The vacuum pump 170 exhausts the gas in the robot chamber 140 and the alignment chamber 146 via the valve 172. Thereby, the robot chamber 140 and the alignment chamber 146 are maintained in a vacuum atmosphere. The vacuum pump 170 exhausts the gas in the electron column 102 and the drawing chamber 103 via the valve 174. As a result, the inside of the electron column 102 and the drawing chamber 103 are maintained in a vacuum atmosphere. Further, the vacuum pump 170 exhausts the gas in the load lock chamber 130 via the valve 176. Thereby, the inside of the load lock chamber 130 is controlled to a vacuum atmosphere as necessary. In addition, gate valves 132, 134, and 136 are disposed at boundaries between the loading / unloading port 120, the load lock chamber 130, the robot chamber 140, and the drawing chamber 103.

  Here, FIG. 1 shows components necessary for explaining the first embodiment. The drawing apparatus 100 may normally include other necessary configurations. The transfer robots 122 and 142 are, for example, multi-axis robots. The transport robots 122 and 142 may be any mechanical mechanism such as an elevator mechanism or a rotation mechanism.

  FIG. 2 is a top conceptual view showing an example of an EUV mask having defects in the first embodiment. FIG. 3 is a conceptual cross-sectional view showing a cross section of the EUV mask of FIG. The EUV mask has a multilayer film 12 in which, for example, 40 layers of molybdenum (Mo) having a thickness of 2.9 nm and silicon (Si) having a thickness of 4.1 nm are alternately laminated on the glass substrate 10. Is formed. Then, a cap film 14 such as ruthenium (Ru) is formed on the entire surface of the multilayer film 12. The cap film 14 is exposed in the region that reflects EUV light. On the other hand, in the region that does not reflect EUV light, an absorber film 16 that absorbs EUV light and an antireflection film 18 are sequentially formed on the cap film 14. Here, as shown in FIG. 2A and FIG. 3A, when the defect 40 of the multilayer film 12 is present in the region 42 where the absorber film 16 does not exist, the phase of the reflected EUV light is shifted. As a result, when the pattern is transferred onto the semiconductor wafer with the manufactured EUV mask, the position of the pattern is shifted. Therefore, in the first embodiment, as shown in FIG. 2B and FIG. 3B, after the patterning, the position of the defect 40 is located in the region 44 where the absorber film 16 exists, as shown in FIG. Drawing is performed by shifting the pattern layout from the positions shown in a) and FIG. In other words, the anti-reflection film 18 is drawn on the substrate 101, which is an EUV mask blank coated with the resist film 20, by the drawing apparatus 100, the resist is developed, and the resist pattern formed by the resist film 20 remaining after the development is used as a mask. The substrate film 101 is patterned by etching the absorber film 16 and removing the remaining resist film 20 by ashing. An EUV mask is manufactured by such patterning. Then, after such patterning, the pattern layout is shifted when drawing by the drawing apparatus 100 so that the position of the defect 40 is in the region 44 where the absorber film 16 exists. In order to shift the pattern layout, it is first necessary to specify a defect position. For this purpose, first, a phase defect inspection of the substrate 101 is performed by a phase defect inspection apparatus (not shown) before drawing.

  FIG. 4 is a conceptual diagram showing an example when a pattern is drawn on a substrate having defects in the first embodiment. ALN-marks 52 and 54 are formed on the substrate 101. The phase defect inspection apparatus inspects the presence or absence of the defect 40 on the substrate, and measures the defect position and the defect size with reference to the ALN-marks 52 and 54. As a result, the user can acquire defect position and defect size information based on the positions of the ALN-marks 52 and 54 in advance before drawing. For example, the defect position is indicated by coordinates (x, y) of the center position of the defect with reference to the coordinates of the positions of the ALN-marks 52 and 54. In addition, the defect size is indicated by a diameter (D) of a circle that extends to the maximum outline of the defect with the defect position coordinate as the center. Obtaining information on the defect position and the defect size, the user creates pattern data in which the pattern layout is shifted so that the position of the defect 40 is within the region 44 where the absorber film 16 exists after patterning.

  For example, the example of FIG. 4 shows a case where the defect 40 exists in a partial area 56 of the drawing area 50 of the substrate 101. If the pattern layout is used as it is, the defect 40 is located in the region 42 where the absorber film 16 does not exist, which causes a phase defect. On the other hand, in the first embodiment, the pattern layout is shifted so that the partial region 56 becomes the partial region 58, so that the pattern for drawing is positioned so that the defect 40 is located in the region 44 where the absorber film 16 exists. Correct the data. In the pattern data for drawing, information on a shift amount and a shift direction in which the pattern layout is shifted is defined as attribute information, for example. For example, the coordinates (x, y) of the position shifted with reference to the coordinates of the positions of the ALN-marks 52 and 54 are defined. A shift amount and a shift direction for shifting the pattern layout can be specified by such coordinates. As described above, drawing pattern data in which the shift amount and shift direction for shifting the pattern layout are defined is input from the outside and stored in the storage device 109.

  FIG. 5 is a conceptual cross-sectional view of a substrate to be drawn in the first embodiment. In FIG. 5, a substrate 101 to be drawn is configured as follows. A multilayer film 12 in which, for example, 40 layers of molybdenum (Mo) having a thickness of 2.9 nm and silicon (Si) having a thickness of 4.1 nm are alternately laminated on the glass substrate 10 is formed on the entire surface of the glass substrate 10. Yes. Then, a cap film 14 such as ruthenium (Ru) is formed on the entire surface of the multilayer film 12. An absorber film 16 that absorbs EUV light and an antireflection film 18 are sequentially formed on the entire surface of the cap film 14. For example, tantalum (Ta) is used as the main material of the absorber film 16 and the antireflection film 18. Then, a resist film 20 is formed on the antireflection film 18. When a positive resist material is used, the region 44 where the absorber film 16 remains after patterning is a non-irradiation region (non-drawing region) of the electron beam 200, and the region 42 where the absorber film 16 does not remain is the electron beam 200. It becomes an irradiation area (drawing area). When a negative resist material is used, a region 44 where the absorber film 16 remains after patterning is an irradiation region (drawing region) of the electron beam 200, and a region 42 where the absorber film 16 does not remain is not irradiated with the electron beam 200. A region (non-drawing region). In other words, the region where the resist film 20 remains after developing the resist becomes the region 44 where the absorber film 16 remains, and the region where the resist film 20 does not remain becomes the region 42 where the absorber film 16 does not remain. Further, a conductive film 22 such as chromium nitride (CrN) is formed on the back surface of the glass substrate 10.

  On the side surface of the glass substrate 10, an ID 30 that can be optically read by the reading device 121 is encoded and formed. The ID 30 is formed of a data matrix defined by the SEMI standard, for example. The board information associated with the ID 30 is input from the outside and stored in the storage device 109. As the substrate information, information on defect positions and defect sizes based on the positions of the ALN-marks 52 and 54 measured in advance by the phase defect inspection apparatus before the substrate 101 is set on the drawing apparatus 100 is defined. . For example, the defect position is indicated by coordinates (x2, y2) of the center position of the defect with reference to the coordinates of the positions of the ALN-marks 52 and 54. In addition, the defect size is indicated by a diameter (D) of a circle that extends to the maximum outline of the defect with the defect position coordinate as the center.

  Here, the pattern data and the substrate information are stored in one and the same storage device 109 in FIG. 1, but the present invention is not limited to this. Needless to say, they may be stored in separate storage devices. It is also preferable that the pattern data is associated with the ID described above.

  FIG. 6 is a flowchart showing main steps of the drawing method according to the first embodiment. 6, the drawing method according to the first embodiment includes an ID acquisition step (S102), a defect coordinate / size acquisition step (S104), a partial pattern data / shift amount and direction acquisition step (S106), and a verification step (S106). S108), ALN-mark detection step (S110), absorber region detection step (S120), offset value calculation step (S122), ALN-mark detection step (S124), offset step (S126), A series of steps called a drawing processing step (S130) is performed.

  First, the drawing data processing unit 76 reads pattern data stored in the storage device 109, performs a plurality of stages of data conversion processing, and generates shot data unique to the drawing apparatus. At that time, the drawing area is virtually divided into grid-like meshes, and a dose map defining the dose for each mesh is created. The drawing data processing unit 76 is an example of a dose map creation unit. The dose map is stored in the storage device 108. In parallel with this process, the following pattern data and substrate are specified.

  As the ID acquisition step (S <b> 102), when the substrate 101 is placed at the carry-in / out port 120, the reading device 121 reads the ID 30 from the substrate 101. The ID acquisition unit 60 inputs and reads the read ID 30 from the reading device 121. The reading device 121 or the ID acquisition unit 60 is an example of a reading unit.

  In the defect coordinate / size acquisition step (S104), the defect coordinate / size acquisition unit 62 refers to the substrate information stored in the storage device 109, and the position of the defect 40 on the substrate 101 associated with the read ID 30. And defect size information indicating the size of the defect 40 are read out.

  As the partial pattern data / shift amount and direction acquisition step (S106), the partial pattern data / shift amount and direction acquisition unit 64 is a portion of the pattern data stored in the storage device 109 corresponding to an area including at least the defect 40. Input pattern data. Further, the partial pattern data / shift amount and direction acquisition unit 64 simultaneously inputs information on the shift amount and shift direction in which the pattern layout is shifted.

  As a verification step (S108), the verification unit 66 inputs partial pattern data, defect position information, and defect size information for at least a region including a defect in the pattern data. It is verified whether or not the pattern layout is configured so that the defect 40 is located in the remaining region 44. By superimposing the coordinates of the defect position information and the size of the defect size information on the layout of the partial pattern defined in the partial pattern data, it is verified whether or not the entire defect 40 is included in the region 44 where the absorber film 16 remains. That's fine. For example, when a positive resist is used, a non-irradiation region (non-drawing region) of the electron beam 200 becomes a region 44 where the absorber film 16 remains after patterning. When a negative resist is used, the irradiation region (drawing region) of the electron beam 200 becomes a region 44 where the absorber film 16 remains after patterning. Therefore, it can be verified if it is determined from the partial pattern data whether or not the region is the region irradiated with the electron beam 200. As a result of the verification, when the defect 40 is located in the region 44 where the absorber film 16 remains after patterning (in the case of OK), the process proceeds to the ALN-mark detection step (S110). When the defect 40 is not located in the region 44 where the absorber film 16 remains after patterning (in the case of NG), the process proceeds to the absorber region detection step (S120). The verification result is output by an output device (not shown). For example, it is output to a monitor, a printer or the like. Further, it may be output to the outside. Moreover, you may memorize | store in the memory | storage devices 108 and 109 grade | etc.,.

  As described above, in the first embodiment, the defect information 40 is formed in the region 44 where the absorber film 16 remains after the patterning by using the actual drawing pattern data and the substrate information correlated with the ID formed on the actual substrate 101. It is verified whether the pattern layout is configured so as to be positioned. Thereby, it can be determined whether the combination of the pattern data to be used and the drawing target substrate 101 is correct. Furthermore, since verification is performed using the actual drawing pattern data and the defect position and defect size of the substrate information, whether or not the pattern layout is actually shifted by the pattern data so that the defect position is hidden by the absorber film 16. Can also be verified. Therefore, certainty can be improved more than verification by simply determining the correlation between the substrate ID and the pattern data.

  In the ALN-mark detection step (S110), the drawing unit 150 moves the XY stage 105 to a position where the electron beam 200 can irradiate the ALN-marks 52, 54, scans the ALN-marks 52, 54, and performs ALN-scanning. -The positions of the marks 52 and 54 are detected. Here, reflected electrons of the irradiated electron beam 200 are detected by the detector 212 and output to the detection circuit 164. The detection circuit 164 converts the positions of the ALN-marks 52 and 54 into digital signals and outputs them to the computer unit 110. The ALN-mark position acquisition unit 70 receives the position information of the ALN-marks 52 and 54 output from the detection circuit 164, thereby acquiring the positions of the ALN-marks 52 and 54.

  In the drawing process step (S130), the drawing unit 150 applies the electron beam 200 based on the pattern data in which the pattern layout is configured such that the defect 40 is located in the region 44 where the absorber film 16 remains after patterning. Using this, a pattern is drawn on the substrate 101. At this time, at least one position of the ALN-marks 52 and 54 is used as a reference of the drawing coordinate system. Thereby, a defect can be reliably located in the area | region 44 with which the absorber film | membrane 16 remains.

  FIG. 7 is a conceptual diagram illustrating an example of a substrate transport path in the drawing apparatus according to the first embodiment. After the ID is read by the reading device 121, the substrate 101 disposed at the carry-in / out port 120 is transferred to a support member in the L / L chamber 130 by the transfer robot 122 after opening the gate valve 132. After the gate valve 132 is closed, the inside of the L / L chamber 130 is evacuated by the vacuum pump 170. Next, the substrate 101 placed on the support member in the L / L chamber 130 opens the gate valve 134 and is then transferred by the transfer robot 142 to the stage in the alignment chamber 146 via the robot chamber 140. Then, the substrate 101 is aligned. Next, the substrate 101 placed on the stage in the alignment chamber 146 opens the gate valve 136 and then is carried into the drawing chamber 103 via the robot chamber 140 by the transfer robot 142. In this way, the substrate 101 is carried into the drawing chamber 103. Then, a pattern is drawn on the substrate 101 in the drawing chamber 103. Then, after the substrate 101 is transferred to the drawing chamber 103, the drawing unit 150 operates as follows under the control of the control circuit 162.

  The drawing unit 150 draws a pattern using the electron beam 200 on the substrate 101 placed on the support pin 106 in the drawing chamber 103. Specifically, the following operation is performed. An electron beam 200 emitted from an electron gun 201 which is an example of an irradiation unit illuminates the entire first aperture 203 having a rectangular hole, for example, a rectangular hole, by an illumination lens 202. Here, the electron beam 200 is first formed into a rectangle, for example, a rectangle. Then, the electron beam 200 of the first aperture image that has passed through the first aperture 203 is projected onto the second aperture 206 by the projection lens 204. The position of the first aperture image on the second aperture 206 is deflection-controlled by the deflector 205, and the beam shape and size can be changed. As a result, the electron beam 200 is shaped. Thus, the electron beam 200 is variably shaped. Then, the electron beam 200 of the second aperture image that has passed through the second aperture 206 is focused by the objective lens 207 and deflected by the deflector 208. As a result, for example, a desired position of the substrate 101 on the continuously moving XY stage 105 is irradiated.

  After the drawing is finished, the substrate 101 is transferred to a support member in the L / L chamber 130 by the transfer robot 142 via the robot chamber 140 after opening the gate valves 134 and 136. After the gate valve 134 is closed, the inside of the L / L chamber 130 is returned to an atmospheric pressure atmosphere. Then, after the gate valve 132 is opened, the substrate 101 is placed at the carry-in / out port 120 by the transfer robot 122.

  As described above, when an OK verification result is obtained in the verification step (S108), the pattern data stored in the storage device 109 may be used as it is. However, if an NG verification result is obtained in the verification step (S108), an EUV mask having a phase defect is manufactured if the pattern data is used as it is. Therefore, in the first embodiment, in such a case, the drawing position is corrected.

  As the absorber region detection step (S120), the detection unit 68 detects the region 44 where the absorber film 16 remains after patterning when the defect 40 is not located in the region 44 where the absorber film 16 remains after patterning as a result of verification. To do. If it cannot be detected, drawing is stopped.

  FIG. 8 is a conceptual diagram showing an example of a defect position after shifting in the first embodiment. When the absorber film 16 is located in the region 42 where the absorber film 16 is removed after patterning without the defect 40 being located in the region 44 where the absorber film 16 remains as shown in FIG. 4, as shown in FIG. The region 44 where the absorber film 16 in which the defect 40 is completely contained remains is detected. Depending on the pattern data input to the drawing apparatus 100, even if the pattern layout is shifted in advance, as shown in FIG. 8B, the defect 40 is completely included in the region 44 where the absorber film 16 remains. It is possible that some of them are protruding. Even in such a case, as shown in FIG. 8A, the region 44 where the absorber film 16 in which the defect 40 is completely contained remains is detected. The detecting unit 68 can grasp the position of the pattern layout defined in the pattern data input from the information on the shift amount and the shift direction defined as the attribute data of the pattern data. The arrangement state of the defect 40 on the shifted pattern layout can be grasped from the defect coordinates and size of the substrate information. Therefore, in the input pattern data, in addition to the case where the entire defect 40 is present in the region 42, the amount of shift is not limited even when a part of the defect 40 as shown in FIG. 8B protrudes into the region 42. The positional relationship can be grasped from the information of the shifting direction.

  As a first detection method, the detection unit 68 detects a pattern having a size larger than the defect size from the area of the partial pattern data using, for example, the partial pattern data described above. If the defect size is defined by the diameter D, a pattern region having a width wider than the diameter D may be detected.

As a second detection method, it is also preferable to use a dose map stored in the storage device 108.
FIG. 9 is a diagram showing an example of a dose map in the first embodiment. FIG. 9 shows a partial area 55 of the dose map corresponding to the partial area 56 of FIG. In FIG. 9, when a positive resist is used, a mesh area that is black by hatching indicates an irradiation area where the irradiation amount of the electron beam 200 is not zero. That is, it corresponds to the region 44 where the absorber film 16 remains after patterning. Conversely, the mesh area that is not hatched indicates a non-irradiation area where the irradiation amount is zero. That is, it corresponds to the region 42 where the absorber film 16 is not removed after patterning. The detection unit 68 identifies a mesh corresponding to the position of the defect 40 on the irradiation amount map, and a mesh group in an irradiation region (region 44) whose area is larger than the defect size located near the mesh where the defect 40 is located. Is detected. In the example of FIG. 9, it can be seen that there is a mesh group in the irradiation region (region 44) whose area is larger than the defect size in the lower left. On the contrary, the mesh of the irradiation region (region 44) exists in the upper left, upper right, right, and lower right, but the width is the same as the mesh in which the defect 40 is located. Therefore, since it is not known whether the width is larger than the diameter D of the defect 40, it is preferable not to detect such a mesh. Thus, by using the dose map, it is not necessary to calculate the layout from the pattern data (partial pattern data) again, so that the processing time can be shortened.

  In the offset value calculation step (S122), the offset value calculation unit 72 performs correction so as to shift the pattern layout until the defect is completely included (hidden) in the absorber region having an area larger than the detected defect 40. The offset value of is calculated. In other words, when the defect 40 is not located in the region 44 where the absorber film 16 remains after patterning as a result of the verification, the offset value calculation unit 72 causes the defect 40 to be located in the region 16 where the absorber film 16 remains after patterning. An offset value for correcting to is calculated. As the offset value, since the position of the defect 40 on the current layout can be determined from the shift amount and direction information defined as the attribute data of the pattern data input to the drawing apparatus 100, the offset value from that position can be calculated. That's fine. The offset value is preferably defined by coordinates so that the shift amount and direction can be specified.

  As the ALN-mark detection step (S124), the drawing unit 150 detects the positions of the ALN-marks 52 and 54 as in the ALN-mark detection step (S110). The ALN-mark position acquisition unit 70 receives the position information of the ALN-marks 52 and 54 output from the detection circuit 164, thereby acquiring the positions of the ALN-marks 52 and 54.

  In the offset process (S126), the offset processing unit 74 offsets the positions of the ALN-marks 52 and 54 acquired in the ALN-mark detection process (S124) with an offset value. As a result, the positions of the ALN-marks 52 and 54 serving as the reference of the drawing coordinate system are offset. As a result, even if pattern data is used in which the pattern layout is not configured such that the defect 40 is located in the region 44 where the absorber film 16 remains after patterning, the defect 40 is present in the region 44 where the absorber film 16 remains after patterning. Can be positioned.

  Then, as a drawing process step (S130), the drawing unit 150 applies the electron beam 200 based on the pattern data in which the pattern layout is not configured so that the defect 40 is located in the region 44 where the absorber film 16 remains after patterning. Using this, a pattern is drawn on the substrate 101. At this time, at least one position of the offset ALN-marks 52 and 54 is used as a reference of the drawing coordinate system. Thereby, the drawing unit 150 draws the pattern at the position corrected by the offset value. As a result, the defect can be reliably located in the region 44 where the absorber film 16 remains.

  As described above, according to the first embodiment, it is possible to reliably draw the substrate 101 on which the defect 40 exists with the pattern data in which the defect 40 is included in the region of the absorber pattern. Therefore, when the wafer is exposed with the manufactured EUV mask, the phase defect existing in the EUV mask can be prevented from being transferred onto the wafer.

  The embodiments have been described above with reference to specific examples. However, the present invention is not limited to these specific examples.

  In addition, although descriptions are omitted for parts and the like that are not directly required for the description of the present invention, such as a device configuration and a control method, a required device configuration and a control method can be appropriately selected and used. For example, although the description of the control unit configuration for controlling the drawing apparatus 100 is omitted, it goes without saying that the required control unit configuration is appropriately selected and used.

  In addition, all charged particle beam writing apparatuses and charged particle beam writing methods that include elements of the present invention and that can be appropriately modified by those skilled in the art are included in the scope of the present invention.

10 Glass substrate 12 Multilayer film 14 Cap film 16 Absorber film 18 Antireflection film 20 Resist film 22 Conductive film 30 ID
40 Defect 42, 44 region 50 Drawing region 52, 54 ALN-mark 55, 56, 58, 59 Partial region 60 ID acquisition unit 62 Defect coordinate / size acquisition unit 64 Partial pattern data / shift amount and direction acquisition unit 66 Verification unit 68 Detection unit 70 ALN-mark position acquisition unit 72 Offset value calculation unit 74 Offset processing unit 76 Drawing data processing unit 78 Memory 100 Drawing device 101 Substrate 102 Electron barrel 103 Drawing chamber 105 XY stage 106 Support pins 108, 109 Storage device 110 Computer Unit 120 Loading / unloading port 121 Reader 122, 142 Transport robot 130 Load lock chamber 132, 134, 136 Gate valve 140 Robot chamber 146 Alignment chamber 150 Drawing unit 160 Control unit 162 Control circuit 164 Detection circuit 170 True Pump 172, 174, 176 Valve 200 Electron beam 201 Electron gun 202 Illumination lens 203, 410 First aperture 204 Projection lens 205, 208 Deflector 206, 420 Second aperture 207 Objective lens 212 Detector 330 Electron beam 340 Sample 411 Opening 421 Variable shaping opening 430 Charged particle source

Claims (3)

A reading unit that reads an identifier from a substrate on which an absorber film that absorbs extreme ultraviolet (EUV) light is formed and an optically readable identifier (ID) is formed;
A storage unit that stores defect position information indicating a position of a defect on the substrate, defect size information indicating the size of the defect, and pattern data for drawing, which are associated with the identifier;
Input partial pattern data for at least the region including the defect in the pattern data, the defect position information, and the defect size information, and the defect is located in a region where the absorber film remains after patterning. A verification unit that verifies whether or not the pattern layout is configured,
A drawing unit that draws a pattern on the substrate using a charged particle beam based on pattern data in which a pattern layout is configured such that the defect is located in a region where the absorber film remains after patterning;
A dose map creating unit for creating a dose map for irradiating the substrate with a charged particle beam;
As a result of the verification, when the defect is not located in the region where the absorber film remains after patterning, a detection unit that detects the region where the absorber film remains after patterning using the dose map;
As a result of verification, when the defect is not located in a region where the absorber film remains after patterning, an offset value for calculating an offset value for correcting the defect so as to be located in a region where the absorber film remains after patterning A calculation unit;
With
The offset value calculating unit calculates an offset value for correcting the defect so that the defect is located in the detected area ;
In the irradiation map, the drawing region is virtually divided into grid-like meshes, the irradiation amount for each mesh is defined, and a group of meshes having a non-zero irradiation amount whose area is larger than the defect size is the absorber film. The charged particle beam drawing apparatus is characterized in that it is detected as a remaining region .   The drawing unit further draws a pattern at a position corrected by the offset value based on pattern data in which a pattern layout is not configured so that the defect is located in a region where the absorber film remains after patterning. The charged particle beam drawing apparatus according to claim 1. A step of reading the identifier from a substrate on which an absorber film that absorbs extreme ultraviolet (EUV) light is formed and an optically readable identifier (ID) is formed;
Among the pattern data, the storage unit stores defect position information indicating the position of the defect on the substrate, defect size information indicating the size of the defect, and pattern data for drawing, which are associated with the identifier. The pattern layout is configured so that the partial pattern data, the defect position information, and the defect size information for at least the region including the defect are read, and the defect is located in the region where the absorber film remains after patterning Verifying whether or not
Drawing a pattern on the substrate using a charged particle beam based on pattern data in which a pattern layout is configured such that the defect is located in a region where the absorber film remains after patterning;
Creating a dose map for irradiating the substrate with a charged particle beam;
As a result of verification, when the defect is not located in a region where the absorber film remains after patterning, a step of detecting a region where the absorber film remains after patterning using the dose map;
As a result of verification, when the defect is not located in a region where the absorber film remains after patterning, a step of calculating an offset value for correcting the defect so that the defect is located in a region where the absorber film remains after patterning; ,
With
Calculating an offset value for correcting the defect so that the defect is located in the detected area ;
In the irradiation map, the drawing region is virtually divided into grid-like meshes, the irradiation amount for each mesh is defined, and a group of meshes having a non-zero irradiation amount whose area is larger than the defect size is the absorber film. A charged particle beam writing method characterized in that the region is detected as a region where the residual region remains .

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