CN115096208A - Broad spectrum ellipsometry measuring equipment - Google Patents

Abstract

The invention provides a wide-spectrum ellipsometry measuring device which comprises a workpiece table, a wide-spectrum light source, an incident light adjusting assembly, a light beam converging module, an alignment system, a control system and a detector, wherein the wide-spectrum light source emits a wide-band light beam; the incident light adjusting component decomposes the broadband light beam into at least two beams of light beams with different wavelengths and adjusts the transmission directions of the light beams with different wavelengths; the light beam converging module is used for converging light beams with different wavelengths to form different measuring light spots on the surface of the sample; the alignment system is used for acquiring the distribution information of the measuring light spots on the surface of the sample; the control system adjusts at least one of the workpiece table, the light beam convergence module and the incident light adjusting assembly based on the distribution information; the detector collects reflected and/or scattered light beams of light beams with different wavelengths after passing through a sample to be measured so as to acquire measurement information. By the method and the device, the size of the measuring light spot is reduced, and the accuracy and the repeatability of the measuring data of the surface topography parameters of the sample are improved.

Description

A Broad Spectrum Ellipsometry Device

technical field

The invention relates to the technical field of optical equipment, in particular to a wide-spectrum ellipsometry measurement equipment.

Background technique

An ellipsometer is an optical measurement device used to detect film thickness, optical constants, and material microstructure. In order to meet the measurement limitations of the sample to be tested 1 based on its own material system and structure, it is necessary to inject a broad spectrum light with wavelengths covering the ultraviolet band to the infrared band into the sample 1 to be tested. The broad-spectrum light can cover more material systems and structures, so it can sensitively detect samples 1 of different materials and structures. At the same time, since the ellipsometer is not in contact with the sample to be tested 1 during optical detection, and the sample 1 to be tested is not damaged and does not require vacuum, the broad-spectrum ellipsometer using a broad spectrum as a light source has become a mainstream ellipsometer measuring equipment.

Referring to Fig. 1, a broad spectrum ellipsometer in the prior art is shown. After the broad-spectrum outgoing light emitted by the broad-spectrum light source 10 enters the polarizing system 11 through the optical fiber, it is converged by the lens 17 and then reflected on the surface of the sample 1 (eg, a semiconductor device such as a wafer) to be tested. The reflected light beam passes through the lens 16 and then passes through the analyzer system 30 and then is captured by the detector 40. At the same time, the alignment system 20 ensures that the outgoing light beam after passing through the lens 16 is aligned with the designated measurement pad area based on image matching. Finally, the detector 40 performs spectral analysis on the reflected light beam reflected from the Pad area after passing through the lens 16 , so as to measure the film thickness and critical dimension (CD) of the sample 1 to be tested.

After the front-end process of the wafer is completed, multiple regularly arranged and very small pad areas are formed on the surface of the circular silicon wafer to perform point-by-point inspection in a matrix form. The size of the Pad area with a rectangular shape is very small, and usually the maximum side length of the Pad area is only about 100 microns. Therefore, in the measurement process using a wide-spectrum ellipsometer, it must be ensured that the light spot obliquely directed to the wafer must be concentrated within the measurement pad area. However, since the incident beam covers a wide spectrum, it is impossible for the focal points formed by the different wavelengths of light to pass through the lens 17 to be in the same focal plane, and due to the dispersion effect, the shape of the spot is larger than the measurement pad area. . For example, as shown in FIG. 2 , the length of the long axis of the elliptical light spot formed on the image plane by the incident light beam is about 206 μm, and the elliptical light spot has obviously exceeded the measurement Pad area. Therefore, in order to solve the aforementioned problems, the wide-spectrum ellipsometer in the prior art usually intercepts the spot size by adding a slit in the optical path of the polarization system 11 . However, in actual use, it is found that the size of the light spot formed by cutting through the slit is still relatively large. Therefore, the accuracy and repeatability of the measurement data of the pad region by the wide-spectrum ellipsometer in the prior art are poor.

In view of this, it is necessary to improve the wide-spectrum ellipsometer in the prior art to solve the above problems.

SUMMARY OF THE INVENTION

The purpose of the present invention is to disclose a wide-spectrum ellipsometry device, which is used to solve the aforementioned defects of the wide-spectrum ellipsometry device in the prior art, and especially to reduce the size of the light spot formed on the surface of the sample to be measured, In order to improve the accuracy and repeatability of the measurement of topographic parameters such as film thickness and critical dimensions of the sample to be tested.

In order to achieve the above purpose, the present invention provides a wide-spectrum ellipsometry measurement device, including a workpiece stage, a wide-spectrum light source, an incident light adjustment component, a beam convergence module, an alignment system, a control system and a detector;

The workpiece table is used to carry and drive the sample to be tested;

The broad-spectrum light source is used for emitting a broad-band light beam;

The incident light adjustment component decomposes the broadband light beam into at least two beams of different wavelengths, and adjusts the transmission direction of the beams of different wavelengths;

the beam converging module is used for converging the beams of different wavelengths to form different measurement spots on the surface of the sample;

The alignment system is used to obtain distribution information of the measurement spot on the sample surface, where the distribution information includes spot position and spot size;

The control system, based on the distribution information, adjusts at least one of the workpiece stage, the beam converging module, and the incident light adjusting component, so that the different measurement light spots have at least a partial overlap area;

The detector collects the reflected and/or scattered light beams of the light beams of different wavelengths after passing through the sample to be measured, so as to obtain measurement information.

As a further improvement of the present invention, the incident light adjustment component includes:

a first beam splitter and a first reflection mirror; the beam converging module includes a first lens and a second lens; the first beam splitter decomposes the broadband light beam into a first sub-beam and a second sub-beam, the The wavelengths of the first sub-beam and the second sub-beam are different; the first sub-beam is converged to the sample surface through the first lens to form a first measurement spot; the second sub-beam is passed through the first sub-beam After being reflected by the mirror, it is converged by the second lens to form a second measurement spot on the surface of the sample.

As a further improvement of the present invention, the first sub-beam is coaxial with the broadband beam, and the optical axis of the second sub-beam and the broadband beam have an included angle.

As a further improvement of the present invention, the control system adjusts the focal length of the first lens and/or the second lens based on the distribution information to make the first measurement spot coincide with the first measurement spot .

As a further improvement of the present invention, the incident light adjustment component further includes: a second reflector and a second beam splitter;

The first sub-beam is condensed by the first lens and penetrates the second beam splitter, and then enters the sample surface to form the first measurement spot;

The second sub-beam is converged by the second lens and then reflected by the second mirror to the second beam splitter, and the second beam splitter reflects part of the second sub-beam to form the second measurement spot.

As a further improvement of the present invention, the first sub-beam and part of the second sub-beam reflected by the second beam splitter are incident on the surface of the sample to be tested at the same incident angle.

As a further improvement of the present invention, the second reflector is a swingable reflector.

As a further improvement of the present invention, the incident light adjustment component further includes a first shutter and a second shutter, the first shutter is disposed on the incident surface side of the first lens, and is used to control the first sub-beam The second shutter is arranged on the side of the incident surface of the second lens, and is used to control the switch of the second sub-beam.

As a further improvement of the present invention, the control system adjusts the vertical position of the workpiece table, the focal length of the beam converging module, and the inclination angle of the incident light adjustment component based on the light spot information, so that the first quantity The measuring light spot is coincident with the first measuring light spot.

As a further improvement of the present invention, the wavelength range of the broadband light beam is 200-1700 nm.

As a further improvement of the present invention, the wavelength of the first sub-beam is 1100-1700 nm, the wavelength of the second sub-beam is 200-1100 nm; or the wavelength of the first sub-beam is 200-1100 nm, the The wavelengths of the two sub-beams are 1100-1700 nm.

Compared with the prior art, the beneficial effects of the present invention are:

In the present application, the broadband beam is decomposed into at least two beams of different wavelengths, and the beams of different wavelengths form different measurement spots on the sample surface through the beam converging module and the incident light adjustment component, and the different wavelengths The measurement spot is formed on the sample surface with at least a partial overlapping area, so that different measurement spots all fall within the measurement pad area of the sample surface, thereby reducing the size of the measurement spot formed by the incident beam on the sample surface to be measured, and improving The accuracy and repeatability of the measurement data of the topographical parameters such as film thickness and critical dimensions of the sample to be tested were investigated.

Description of drawings

Fig. 1 is the schematic diagram of the wide spectrum ellipsometer in the prior art;

2 is a schematic diagram of a measurement spot formed in the Pad region of the wafer surface based on the wide-spectrum ellipsometer shown in FIG. 1;

Fig. 3 is the schematic diagram of the wide-spectrum ellipsometry measurement device disclosed by the present invention;

4 is a schematic diagram of a first measurement spot formed in the Pad area of the wafer surface based on the outgoing light of the wide-spectrum ellipsometry device shown in FIG. 3 through the first lens, wherein the light passing through the first lens The wavelength of the outgoing light is 1100-1700nm;

5 is a schematic diagram of a second measurement spot formed in the Pad area of the wafer surface based on the outgoing light of the wide-spectrum ellipsometry device shown in FIG. 3 through the second lens, wherein the light passing through the second lens The wavelength of the emitted light is 200-1100nm;

6 is a schematic diagram of the wide-spectrum ellipsometry device disclosed in another embodiment of the present invention;

7 is a schematic diagram of a wide-spectrum ellipsometry device disclosed in another embodiment of the present invention;

Fig. 8 is the schematic diagram that the workpiece table carries the sample to be tested;

FIG. 9 is a structural block diagram of the wide-spectrum ellipsometry device disclosed in the present invention.

Detailed ways

The present invention will be described in detail below with reference to the various embodiments shown in the accompanying drawings, but it should be noted that these embodiments do not limit the present invention. Equivalent transformations or substitutions all fall within the protection scope of the present invention.

The wide-spectrum ellipsometry device disclosed in this embodiment can be used to perform post-development inspection (ADI), post-etch inspection (AEI) and other process sections of the line width, sidewall angle ( SWA), height/depth and other critical dimension (CD) features, film thickness or overall topography measurement, with high speed, accuracy and non-destructive characteristics, is one of the key equipment for semiconductor front-line inspection.

Referring to FIG. 3 to FIG. 5 , FIG. 8 and FIG. 9 , the present embodiment discloses a broad spectrum ellipsometry measurement device. In this embodiment, a wide-spectrum ellipsometry measurement device is used to measure the surface topography of a sample to be measured 1 (ie, a sample, such as a wafer, an IC device, etc.), including: a workpiece stage 100 that emits a broad-band beam The wide-spectrum light source 10 of 110 , the alignment system 20 perpendicular to the sample to be tested 1 , the incident light adjustment component 80 in the incident light path, the beam converging module 70 , the control system 50 and the detector 40 . The workpiece stage 100 is used to carry and drive the sample to be measured 1 , to drive the sample to be measured to move in any direction of the X/Y/Z axis, and to cooperate with subsequent alignment, focus adjustment, or overlapping processing operations of two measurement spots. The broad-spectrum light source 10 is used for emitting a broad-band light beam 110 , and the light wavelength range included in the broad-band light beam 110 is 200-1700 nm. The beam converging module 70 includes a first lens 14 , a second lens 15 and a lens 16 , and the aforementioned lenses can be regarded as one lens, or can be regarded as a lens group in which a plurality of lenses are sequentially arranged along the same optical axis. The incident light adjustment component 80 decomposes the broadband light beam into at least two light beams with different wavelengths (eg, the first sub-beam 121 and the second sub-beam 122 described below), and adjusts the transmission directions of the different wavelength light beams. The beam converging module 70 is composed of a plurality of independently controlled lenses for converging beams of different wavelengths to form different measurement spots (ie, the first measurement spot and the second measurement spot described below) on the sample surface. The alignment system 20 is vertically arranged above the sample 1 to be measured, and is used to obtain the distribution information of the measurement light spot on the sample surface, and the distribution information includes the spot position and the spot size. The control system 50 adjusts at least one of the workpiece stage 100 , the beam converging module 70 , and the incident light adjusting component 80 based on the distribution information, so that the different measurement light spots have at least a partial overlap area, so that light beams with different wavelengths are incident on the same measurement point. The detector 40 is used to collect reflected and/or scattered light beams of different wavelengths of light beams after passing through the sample to be measured, so as to obtain measurement information.

After two or three or more oblique incident beams generated by the incident light adjustment component 80 are incident on the same measurement point of the sample 1 to be tested, reflection and/or reflection occurs on the surface of the sample 1 to be tested (ie, the sample surface). Scattered to form reflected light beams and/or scattered light beams and captured by the detector 40 , so as to analyze the parameters to be measured of the sample to be measured 1 based on the captured light signals. The detector 40 may be a spectrometer in this embodiment. The reflected light beam and/or the scattered light beam is captured by the detector 40 after passing through the lens 16, and at the same time, the alignment system 20 ensures that the outgoing light beam after passing through the lens 16 is aligned with the designated measurement pad on the surface of the sample 1 to be tested based on image matching. area. Finally, the light beam reflected and/or scattered from the measuring Pad area on the surface of the sample 1 to be tested is subjected to spectral analysis by the detector 40 after passing through the lens 16, so as to realize the film thickness of the sample 1 to be tested. and critical dimension (CD) to be measured. The spectral coverage range of the outgoing broadband light beam 110 is 190-2500 nm, and can be further optionally 200-1700 nm.

The incident light adjusting component 80 decomposes the broadband light beam 110 with a wavelength of 200-1700 nm in the incident light path into at least two incident light beams with different wavelengths, wherein the incident light beams cover different wavelength ranges. The applicant points out that in each embodiment of the present application, the aforementioned broadband light beam 110 with a wavelength of 200-1700 nm is exemplarily shown to be decomposed into two incident light beams with different wavelength ranges. The applicant pointed out that the broadband beam 110 can also be decomposed into three or more incident beams by means of multi-component optical mirrors and reflecting mirrors, as long as the multiple incident beams are obliquely directed towards the same measurement point of the sample 1 to be tested, so that The size of the elliptical measuring light spot (especially the long axis size of the elliptical measuring light spot) is effectively reduced, and the influence of the dispersion effect on the measuring light spot size during the focusing process is reduced.

Exemplarily, as shown in FIG. 3 , the incident light adjustment component 80 includes: a first beam splitter 12 , a first reflection mirror 13 and a first beam splitter 12 . The beam converging module 70 includes a first lens 14 and a second lens 15 . The first beam splitter 12 decomposes the broadband light beam 110 into a first sub-beam 121 and a second sub-beam 122 with different beam wavelengths. The first sub-beam 121 passes through the first lens 14 to form a first focused beam 141. The beam 141 converges on the sample surface to form a first measurement spot as shown in FIG. 4 ; the second sub-beam 122 is reflected by the first mirror 13 and then passes through the second lens 15 to form the same focus as the first focused beam 141 The plane second focused beam 152 forms a second measurement spot as shown in FIG. 5 on the surface of the sample. The first sub-beam 121 is coaxial with the broadband beam 110, and the optical axis of the second sub-beam and the broadband beam 110 have a certain angle, and the angle can be adjusted by the position of the first beam splitter, so as to form a second measurement The angle formed by the optical axis of the second sub-beam 122 of the light spot and the optical axis of the broadband light beam 110 can be adjusted to adjust the spot positions of the first measurement spot and the second measurement spot to achieve two measurements. Parts of the metering spots overlap or overlap.

In the embodiment, the wavelength of the first sub-beam 121 is 1100-1700 nm, and the wavelength of the second sub-beam 122 is 200-1100 nm. The broad-band light beam 110 can meet the wide-spectrum detection requirements from ultraviolet, visible light to near-infrared wavelengths. Meanwhile, the lens 16 , the first lens 14 and the second lens 15 are all converging lenses, and can be axially adjusted along the optical axes of each other. As an optional solution, the broad-band light beam 110 can also be decomposed into a first sub-beam 121 with a wavelength of 200-1100 nm and a second sub-beam 122 with a wavelength of 1100-1700 nm by the first beam splitter 12 .

Preferably, the wide-spectrum ellipsometry device in this embodiment further includes a polarization system 11 and an analyzer system 30 . The broad-spectrum light source 10 is connected to the polarizing system 11 through an optical fiber to generate a broadband beam 110 with a desired polarization direction as incident light, and the incident light passes through the first beam splitter 12 to decompose the broadband beam 110 into a first sub-beam 121 and a second sub-beam 110 Beam 122. The first sub-beam 121 passes through the first beam splitter 12 and then goes to the first lens 14 , and the first sub-beam 121 is focused and converged by the first lens 14 to the measurement point determined by the alignment system 20 on the surface of the sample 1 to be tested. . The second sub-beam 122 is reflected by the first beam splitter 12 and then incident on the surface of the first reflecting mirror 13 and further reflected to the second lens 15 . The second lens 15 focuses and converges the second sub-beam 122 to the same measurement point determined by the alignment system 20 on the surface of the sample 1 to be tested. In the process of realizing that the first focused beam 141 and the second focused beam 152 are converged to the same measurement point, the first lens 14 and the second lens 15 can independently adjust the focal lengths, so that the first focused beam 141 and the second focused beam 152 Having the same focal plane, in the field of view of the image plane formed by the alignment system 20, the first sub-beam 121 transmitted through the first lens 14 is focused on the first measurement spot on the surface of the sample 1 to be measured and the second beam transmitted through the second beam. The second sub-beam 122 of the lens 15 is focused and converged to the second measurement spot on the surface of the sample 1 to be aligned so that the two measurement spots at least partially coincide. The reflected light beam and/or scattered light beam passing through the surface of the sample to be tested 1 is converged to the analyzer system 30 by the lens 16, and the light beam with the required polarization direction is filtered and collected by the spectrometer 40, and then the parameters to be measured are obtained by analysis.

As shown in FIG. 9 , the control system 50 is selected from a single-chip microcomputer or an integrated circuit chip or a computer device that includes a logic operation storage function and has built-in executable computer program instructions. The control system 50 is connected to the workpiece stage 100 , the beam converging module 70 , the incident light adjusting assembly 80 and the detector 40 through cables and corresponding interfaces (not shown). The control system 50 adjusts one or more of the vertical position of the workpiece stage 100, the focal length of the beam converging module 70, or the inclination angle of the incident light adjusting component 80 based on the light spot information, so that the first measurement spot and the second measurement spot are partially coincident or completely coincident. Specifically, the control system 50 controls the workpiece stage 100 to reciprocate in the vertical direction, so as to determine the position of the workpiece stage when the first sub-beam 121 forms a first measurement spot with a minimum size on the surface of the sample 1 through the alignment system 20 The workpiece stage 100 is fixed at this position, and the control system 50 adjusts the first lens 14 and/or the second lens based on the spot positions and spot sizes (ie, distribution information) of the first and second measurement spots. The focal length of 15 is detected in the alignment system 20 and the focal length correction results of each lens are fed back to the control system 50 to ensure that the first measurement spot and the second measurement spot in the field of view coincide or partially coincide, and can ensure The clarity and position accuracy of the first measurement spot and the second measurement spot.

Referring to FIG. 4, the light emitted from the first lens 14 (that is, after the first sub-beam 121 with a wavelength of 1100-1700 nm is converged in the first focusing optical path 141) is formed in the measurement pad area on the wafer surface. A schematic diagram of the first measurement spot. The first measurement spot is elliptical with a long axis length of about 5 microns and a short axis length of about 2 microns, which is significantly smaller than the measurement on the wafer surface by the wide-spectrum ellipsometer in the prior art in FIG. 2 . The size of the measurement spot formed by the pad area. Referring to FIG. 5 , the light emitted from the second lens 15 (ie, after the second sub-beam 122 with a wavelength of 200-1100 nm is converged in the second focusing optical path 152 ) is formed in the measurement pad area on the wafer surface. A schematic diagram of the second measurement spot. The second measurement spot is elliptical, with a long axis length of about 55 microns and a short axis length of about 22 microns, which is also significantly smaller than the pad on the wafer surface of the prior art wide-spectrum ellipsometer in FIG. 2 . The size of the measurement spot formed by the area.

The wide-spectrum ellipsometry device disclosed in the foregoing embodiment decomposes the wide-band light beam 110 into two paths to form a first focusing beam and a second focusing beam with the same focusing plane, which significantly reduces the size of the measurement spot, thereby improving the efficiency of the measurement. The accuracy and repeatability of topographic data measurement such as film thickness and critical dimension (CD) for the sample to be tested.

Exemplarily, based on the technical solutions disclosed in the foregoing embodiments, as shown in FIG. 6 , this embodiment shows another modification example of a wide-spectrum ellipsometry device of the present invention. The wide-spectrum ellipsometry device includes: Incident light conditioning assembly 80 .

Specifically, the incident light adjustment component 80 includes: a first beam splitter 12 , a first reflector 13 , a second reflector 18 and a second beam splitter 19 . Specifically, the first beam splitter 12 decomposes the broadband light beam 110 into a first sub beam 121 and a second sub beam 122 , and the first sub beam 121 is converged by the first lens 14 and penetrates the second beam splitter 19 to form the first sub beam 121 . Focused beam 142, the first focused beam 142 is incident on the surface of the sample to be tested 1 to form a measurement spot; the second sub-beam 122 is reflected by the first mirror 13 and then converged by the second lens 15, and reflected by the second mirror 18 to the second beam splitter 19, the second beam splitter 19 reflects the partial beam of the second sub-beam 122 to generate a second focused beam 155, and the second focused beam 155 is incident on the surface of the sample 1 to be tested to form a second measurement spot, and The first focused beam 142 and the second focused beam 155 have the same angle of incidence. Preferably, the second reflector 18 is a swingable reflector, so the swing adjustment can be performed by the second reflector 18 to adjust the incident angle and the reflection angle of the second sub-beam 122 incident on the second reflector 18 , and at the same time The incident angle and reflection angle of the second sub-beam 122 incident on the second beam splitter 19 are also adjusted, so that the incident angle of the second focused beam 155 formed by the second beam splitter 19 is finally incident on the surface of the measurement sample 1, and Realize the adjustment of the incident angle formed by the second focused beam 155 and the first focused beam 142 respectively, so as to adjust the spot position and/or the spot size of the measurement spot formed by the second focused beam 155 and the first focused beam respectively. , to ensure that the two measurement light spots on the surface of the sample to be measured partially or completely overlap, and to ensure that the measurement light spot always falls within the measurement Pad area.

Exemplarily, based on the technical solutions disclosed in the foregoing embodiments, as shown in FIG. 7 , this embodiment shows another modification example of a wide-spectrum ellipsometry device according to the present invention. The wide-spectrum ellipsometry device includes: Incident light conditioning assembly 80 .

The incident light adjusting assembly 80 further includes: a first shutter 51 and a second shutter 52 . The first shutter 51 is disposed on the incident surface side of the first lens 14 to control the switch of the first sub-beam 121 (ie, to control whether the first sub-beam 121 can be incident on the first lens 14 through the first shutter 51 ), The second shutter 52 is disposed on the incident surface side of the second lens 15 for controlling the on/off of the second sub-beam 122 (ie, controlling whether the second sub-beam 122 can be incident on the second lens 15 through the second shutter 52 ).

The second gate 52 is located in the optical path of the second sub-beam 122 reflected by the first beam splitter 12 to the first mirror 13, and the first sub-beam 121 is transmitted through the first beam splitter 12 and enters the first lens. The first shutter 51 in the optical path of 14, alternatively opens and closes the first door 51 and the second shutter 52 to adjust the formation of the first sub-beam 121 and the second sub-beam 122 on the surface of the sample to be tested 1 respectively. The measurement spots are coincident. The wavelength of the first sub-beam 121 is 1100-1700 nm, and the wavelength of the second sub-beam 122 is 200-1100 nm. In this embodiment, the first door 51 and the second shutter 52 can be opened and closed respectively. Specifically, as shown in FIG. 8 and FIG. 9 , the control system 50 opens the first shutter 51 and closes the second shutter 52 , and controls the workpiece table 100 carrying the measurement sample 1 to reciprocate in the vertical direction, so as to pass The alignment system 20 determines the position where the first measurement spot of the smallest size is formed on the surface of the measurement sample 1 by the first sub-beam 121 . Then, the first shutter 51 is closed and the second shutter 52 is opened. At this time, the position of the workpiece table 100 is maintained in the vertical direction, and the focal length of the second lens 15 and/or the position of the second mirror 18 and/or the second lens 15 are adjusted. The position of the beam splitter 19 and the alignment system 20 are used to observe the position of the second measurement spot formed by the second sub-beam 122 on the surface of the measurement sample 1 to ensure that the second measurement spot coincides with the first measurement spot.

The series of detailed descriptions listed above are only specific descriptions for the feasible embodiments of the present invention, and they are not used to limit the protection scope of the present invention. Changes should all be included within the protection scope of the present invention.

It will be apparent to those skilled in the art that the present invention is not limited to the details of the above-described exemplary embodiments, but that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments are to be regarded in all respects as illustrative and not restrictive, and the scope of the invention is to be defined by the appended claims rather than the foregoing description, which are therefore intended to fall within the scope of the claims. All changes within the meaning and scope of the equivalents of , are included in the present invention. Any reference signs in the claims shall not be construed as limiting the involved claim.

In addition, it should be understood that although this specification is described in terms of embodiments, not each embodiment only includes an independent technical solution, and this description in the specification is only for the sake of clarity, and those skilled in the art should take the specification as a whole , the technical solutions in each embodiment can also be appropriately combined to form other implementations that can be understood by those skilled in the art.

Claims (11)

1. A broad spectrum ellipsometry measuring device is characterized by comprising a workpiece table, a broad spectrum light source, an incident light adjusting assembly, a light beam converging module, an alignment system, a control system and a detector;

the workpiece table is used for bearing and driving a sample to be tested;

the broad spectrum light source is used for emitting a broad band light beam;

the incident light adjusting component decomposes the broadband light beam into at least two beams of light beams with different wavelengths and adjusts the transmission directions of the light beams with different wavelengths;

the light beam converging module is used for converging the light beams with different wavelengths to form different measuring light spots on the surface of the sample;

the alignment system is used for acquiring distribution information of the measuring light spots on the surface of the sample, and the distribution information comprises light spot positions and light spot sizes;

the control system adjusts at least one of the workpiece stage, the light beam converging module and the incident light adjusting assembly based on the distribution information so that the different measuring light spots at least have partial overlapping regions;

and the detector collects the reflected and/or scattered light beams of the light beams with different wavelengths after passing through the sample to be measured so as to obtain measurement information.

2. The broad spectrum ellipsometry apparatus of claim 1, wherein said incident light modulation assembly comprises:

a first beam splitter and a first reflector; the light beam converging module comprises a first lens and a second lens; the first beam splitter splits the broadband light beam into a first sub-beam and a second sub-beam, wherein the first sub-beam and the second sub-beam have different wavelengths; the first sub-beam is converged to the surface of the sample through the first lens to form a first measuring light spot; the second sub-beam is reflected by the first reflector and then converged by the second lens to form a second measuring light spot on the surface of the sample.

3. The broad spectrum ellipsometry apparatus of claim 2, wherein said first sub-beam is coaxial with said broad band beam, and said second sub-beam optical axis has an angle with said broad band beam optical axis.

4. The broad spectrum ellipsometry measurement apparatus of claim 2, wherein the control system adjusts a focal length of the first lens and/or the second lens to coincide the first measurement spot with the first measurement spot based on the distribution information.

5. The broad spectrum ellipsometry apparatus of claim 2, wherein said incident light modulation assembly further comprises: the second reflector and the second spectroscope;

the first sub-beams are converged by the first lens, penetrate through the second beam splitter and then enter the surface of the sample to form the first measuring light spot;

the second sub-beam is converged by the second lens and then reflected to the second beam splitter by the second reflector, and the second beam splitter reflects part of the second sub-beam to form the second measurement light spot.

6. The broad spectrum ellipsometry apparatus of claim 5, wherein the first sub-beam and the portion of the second sub-beam reflected by the second beam splitter are incident on the surface of the sample to be measured at the same incident angle.

7. The broad spectrum ellipsometry apparatus of claim 5, wherein the second mirror is a deflectable mirror.

8. The broad spectrum ellipsometry apparatus of claim 5, wherein said incident light adjusting assembly further comprises a first shutter and a second shutter, said first shutter is disposed at an incident surface side of said first lens for controlling the opening/closing of said first sub-beam, said second shutter is disposed at an incident surface side of said second lens for controlling the opening/closing of said second sub-beam.

9. The broad spectrum ellipsometry apparatus of claim 8, wherein the control system adjusts a vertical position of the stage, a focal length of the beam converging module, and a tilt angle of the incident light adjusting assembly based on the light spot information, so that the first measurement light spot coincides with the first measurement light spot.

10. The broad spectrum ellipsometry apparatus of any one of claims 1 to 9, wherein the wavelength range of the broad band light beam is 200-1700 nm.

11. The broad spectrum ellipsometry apparatus of any one of claims 2 to 9, wherein the first sub-beam has a wavelength of 1100 to 1700nm, and the second sub-beam has a wavelength of 200 to 1100 nm; or the wavelength of the first sub-beam is 200-1100 nm, and the wavelength of the second sub-beam is 1100-1700 nm.

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