Semiconductor measurement system and measurement method, and storage medium

Abstract

The present invention provides a semiconductor measurement system and measurement method, and a storage medium. The semiconductor measurement system comprises a Köhler illumination module, an optical module, and a detection module. The Köhler illumination module sequentially comprises a broad-spectrum light source, a wavelength selection unit, a first lens, a field diaphragm, a second lens, aperture diaphragms, and objective lenses. The optical module comprises a first light splitting unit and a second light splitting unit. The detection module comprises a spectrograph and a camera. By simultaneously providing the Köhler illumination module having the wavelength selection unit, the high-magnification first objective lens, the low-magnification second objective lens, the spectrograph, and the camera, the present invention can implement both large-area thin film thickness measurement, and small-area thin film thickness measurement and microstructure detection, can implement "one-stop" measurement of various semiconductor parameters, and thus can effectively reduce the economic cost of semiconductor measurement and improve the semiconductor measurement efficiency.

Description

Semiconductor measurement system, measurement method and storage medium Technical Field

[0001] The present invention relates to the field of semiconductor processing, and in particular to a semiconductor measurement system, a semiconductor measurement method, and a computer-readable storage medium. Background Art

[0002] During semiconductor processing, film thickness measurement and defect detection of semiconductor thin films are particularly important for verifying and controlling semiconductor processing technology and improving processing yield. Film thickness measurement of semiconductor thin films is mainly used to measure film thickness, material optical properties, critical dimensions, etc., and corresponding equipment includes ellipsoid offset measurement systems, atomic force microscopes, OCD (Optical Critical Dimension) equipment, etc. Semiconductor film defect detection is mainly used to detect semiconductor surface defects, and includes bright / dark field optical image defect detection equipment, macro defect detection equipment, etc. However, due to the limitations of their optical systems or the diffraction limit of the light source, the majority of existing film thickness measurement equipment still has a spot size greater than 30μm, making it difficult to reflect the film thickness of areas less than 30μm, and unable to detect defects in structural features in tiny areas. Therefore, users who need both film thickness measurement and defect detection need to purchase two devices with different functions, which greatly increases the cost of semiconductor processing technology.

[0003] In order to overcome the above-mentioned defects of the existing technology, the field urgently needs an improved semiconductor measurement system to take into account the needs of large-area film thickness measurement, as well as small-area film thickness measurement and microstructure detection, so as to achieve "one-stop" measurement of various semiconductor parameters, thereby effectively reducing the economic cost of semiconductor measurement and improving the efficiency of semiconductor measurement.

[0004] Summary of the Invention

[0005] The following is a brief summary of one or more aspects to provide a basic understanding of these aspects. This summary is not an exhaustive overview of all conceivable aspects and is neither intended to identify key or critical elements of all aspects nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that will be provided later.

[0006] In order to overcome the above-mentioned defects of the prior art, the present invention provides a semiconductor measurement system, a semiconductor measurement method and a computer-readable storage medium, which can perform large-area film thickness measurement, small-area film thickness measurement and microstructure detection respectively by simultaneously including a Köhler illumination module with a wavelength selection unit, a high-magnification first objective lens, a low-magnification second objective lens, a spectrometer and a camera, so as to realize "one-stop" measurement of various semiconductor parameters, thereby effectively reducing the economic cost of semiconductor measurement and improving the efficiency of semiconductor measurement.

[0007] Specifically, the semiconductor measurement system provided according to the first aspect of the present invention includes a Köhler illumination module, an optical module, and a detection module. The Köhler illumination module includes a wide-spectrum light source, a wavelength selection unit, a first lens, a field stop, a second lens, an aperture stop, and an objective lens in sequence. The objective lens includes a first objective lens with a high magnification and a second objective lens with a low magnification. The wavelength selection unit is at least used to filter out a plurality of narrow-band illumination lights with different central wavelengths from the original light provided by the wide-spectrum light source in a time-sharing manner. The aperture stop is conjugate to the plane of the wide-spectrum light source, and the field stop is conjugate to the sample plane where the sample to be measured at the rear end is located, and is used to output a plurality of narrow-band illumination lights under different fields of view in parallel to the first objective lens and the second objective lens. The optical module includes a first spectroscopic unit and a second spectroscopic unit. The first spectroscopic unit is used to first transmit the narrowband illumination light provided by the Köhler illumination module to the first objective lens or the second objective lens, so as to uniformly illuminate the sample to be tested on its object side through the first objective lens or the second objective lens, and then transmit the reflected light generated by the sample to be tested to the second spectroscopic unit on the image side, so as to transmit the reflected light to the spectrometer and camera at the rear end respectively through the second spectroscopic unit. The detection module includes the spectrometer and the camera. The spectrometer is used to collect spectral information of the reflected light provided by the second spectroscopic unit to indicate the average film thickness in the first area of ​​the surface of the sample to be tested that is larger than a preset size. The camera is used to generate a corresponding sample image based on the reflected light transmitted to its detection surface, so as to indicate the film thickness and / or microstructure in the second area of ​​the surface of the sample to be tested that is less than or equal to the preset size.

[0008] Furthermore, in some embodiments of the present invention, the broad-spectrum light source is selected from at least one of LDLS, a xenon lamp, an LED, and a tuned laser. And / or the wavelength selection unit includes a color wheel. The color wheel is provided with a wheel-shaped support having a through hole and multiple narrowband filters of different wavelength ranges. The through hole is used to output the broad-spectrum light provided by the broad-spectrum light source to the spectrometer. Each narrowband filter is configured to sequentially move into the transmission path of the broad-spectrum light as the wheel-shaped support rotates, thereby providing the camera with narrowband illumination light of multiple different central wavelengths in a time-sharing manner. And / or the surfaces of the first lens and / or the second lens are coated with an antireflection coating. And / or the field diaphragm is an adjustable diaphragm for adjusting the size of the illumination area of ​​the sample surface illuminated by the narrowband illumination light to suit the sizes of the first and second areas, respectively. And / or the aperture diaphragm is an adjustable diaphragm for adjusting the brightness of the narrowband illumination light on the sample surface to suit the data acquisition sensitivity and overexposure range of the spectrometer and camera, respectively.

[0009] Furthermore, in some embodiments of the present invention, the Köhler illumination module further includes a collimating unit and a focusing unit. The collimating unit is disposed between the broad-spectrum light source and the wavelength selection unit and utilizes a large-focal-length 90° off-axis parabolic mirror to fold the optical path and direct the divergent original light provided by the broad-spectrum light source into the wavelength selection unit in parallel. The focusing unit is disposed between the wavelength selection unit and the first lens and utilizes a large-focal-length 90° off-axis parabolic mirror to fold the optical path and direct the parallel light output from the wavelength selection unit into the first lens.

[0010] Furthermore, in some embodiments of the present invention, the first lens has a focal length of 14.4 mm and includes a first concave transmissive element with a refractive index of 1.747939 and an Abbe number of 44.62, and a first convex transmissive element with a refractive index of 1.812632 and an Abbe number of 25.25. The light-emitting surface of the first concave transmissive element is in close contact with the light-entering surface of the first convex transmissive element. The second lens has a focal length of 72 mm and includes a second convex transmissive element with a refractive index of 1.812632 and an Abbe number of 25.25, and a second concave transmissive element with a refractive index of 1.594869 and an Abbe number of 67.96. The light-emitting surface of the second convex transmissive element is in close contact with the light-entering surface of the second concave transmissive element, so as to cooperate with the first lens, the field stop, and the aperture stop to output a magnified image of the wide-spectrum light source.

[0011] Furthermore, some embodiments of the present invention further include a controller connected to the wavelength selection unit and the camera, and configured to: provide a plurality of narrowband illumination lights of different central wavelengths to the surface of the sample to be measured on the object side of the first objective lens in a time-sharing manner via the wavelength selection unit, and respectively capture sample images of the corresponding second area under each of the narrowband illumination lights via the camera; determine the relative intensity value and / or relative reflectivity value of each of the sample images to fit the relative intensity curve and / or relative reflectivity curve of the second area with respect to each of the central wavelengths; and perform regression analysis on the relative intensity curve and / or relative reflectivity curve according to a pre-trained regression analysis model to determine the film thickness on the surface of the second area.

[0012] Furthermore, in some embodiments of the present invention, the step of training the regression analysis model includes: obtaining multiple groups of sample data of relative light intensity curves and / or relative reflectivity curves of multiple standard samples with known film thicknesses for multiple different central wavelengths; constructing a regression analysis model to be trained; and inputting the relative light intensity curves and / or relative reflectivity curves of each group of sample data into the regression analysis model, and correcting the learning parameters of the regression analysis model according to the corresponding film thickness to obtain a regression analysis model that has completed the training.

[0013] Furthermore, in some embodiments of the present invention, the controller is further configured to: obtain a first control instruction indicating the size of the area to be measured; and in response to the first control instruction indicating that the area to be measured is less than or equal to the preset size, determine that the area to be measured is the second area, thereby providing a plurality of narrow-band illumination lights with different central wavelengths to the surface of the sample to be measured on the object side of the first objective lens through the wavelength selection unit in a time-sharing manner, and respectively capturing the sample images of the corresponding second area under each of the narrow-band illumination lights through the camera.

[0014] Furthermore, in some embodiments of the present invention, the controller is also configured to: in response to the first control instruction indicating that the area to be measured is larger than the preset size, determine that the area to be measured is the first area, thereby providing wide-spectrum light to the surface of the sample to be measured on the object side of the second objective lens via the wavelength selection unit, and determine the average film thickness in the first area based on the spectral information collected by the spectrometer.

[0015] Furthermore, some embodiments of the present invention further include a moving stage, which is configured to carry and move the sample to be tested laterally between a first position on the object side of the first objective lens and a second position on the object side of the second objective lens, and to move longitudinally in a vertical direction toward or away from the first objective lens and the second objective lens.

[0016] Further, in some embodiments of the present invention, the controller is also configured to: obtain a second control instruction indicating a function type; in response to the second control instruction indicating the execution of the autofocus function, control the mobile stage to first move the marking point or the area to be tested of the sample to be tested into the second field of view of the second objective lens, and then move the sample to be tested up and down, and control the camera to capture a first sample image of the sample to be tested; in response to the first sample image reaching the state of optimal contrast, control the mobile stage to first keep the upper and lower positions of the sample to be tested unchanged, and move the marking point or the area to be tested of the sample to be tested into the first field of view of the first objective lens, and then move the sample to be tested up and down, and control the camera to capture a second sample image of the sample to be tested; and in response to the second sample image reaching the state of optimal contrast, or the sum of the grayscale values ​​of the sample image reaches a peak value, determine that the focusing of the sample to be tested is completed.

[0017] Furthermore, in some embodiments of the present invention, the controller is also configured to: first control the spectrometer to detect the intensity of the reflected light during the process of moving the sample to be tested up and down; and in response to the intensity of the reflected light reaching a peak value, control the camera to capture the first sample image or the second sample image of the sample to be tested.

[0018] Furthermore, in some embodiments of the present invention, the controller is also configured to: control the spectrometer to detect the intensity of the reflected light during the process of moving the sample to be tested up and down; and in response to the intensity of the reflected light reaching a peak, determine the focus position of the sample to be tested based on the current position and the distance between the peak intensity position of the spectrometer and the optimal contrast position or the peak position of the total grayscale value of the camera.

[0019] Furthermore, in some embodiments of the present invention, the microstructure includes defects and / or traces located in semiconductor devices. The controller is further configured to: obtain a second control instruction indicating a functional type; in response to the second control instruction indicating detection of the defect size and / or trace width on the sample to be tested, control the wavelength selection unit to output the narrow-band illumination light of the plurality of different central wavelengths in a time-sharing manner, and control the camera to respectively capture a third sample image illuminated by each narrow-band illumination light; perform image feature extraction and target recognition on each third sample image illuminated by the narrow-band illumination light to respectively determine corresponding recognition results; and average the recognition results of each third sample image to determine the defect size and / or trace width on the sample to be tested.

[0020] In addition, the semiconductor measurement method provided in accordance with the second aspect of the present invention includes the following steps: obtaining a control instruction; in response to the obtained control instruction instructing film thickness detection, and the area to be measured is larger than a preset size, determining that the area to be measured is a first area, thereby providing broad-spectrum light to the surface of the sample to be measured on the object side of the second objective lens via the wavelength selection unit in the semiconductor measurement system provided by the first aspect of the present invention, and determining the average film thickness within the first area based on spectral information collected by the spectrometer; and in response to the obtained control instruction instructing film thickness detection, and the area to be measured is smaller than or equal to the preset size, determining that the area to be measured is a second area, thereby providing a plurality of narrow-band illumination lights of different central wavelengths to the surface of the sample to be measured on the object side of the first objective lens via the wavelength selection unit in a time-sharing manner, and collecting sample images of the corresponding second area under each narrow-band illumination light via a camera in the semiconductor measurement system, and then performing regression analysis based on each sample image to determine the film thickness on the surface of the second area.

[0021] Furthermore, in some embodiments of the present invention, the semiconductor measurement method also includes the following steps: in response to the acquired control instruction indicating the execution of the autofocus function, first moving the mark point or the area to be tested of the sample to be tested into the second field of view of the second objective lens, then moving the sample to be tested up and down, and controlling the camera to collect a first sample image of the sample to be tested; in response to the first sample image reaching the state of optimal contrast, first keeping the upper and lower positions of the sample to be tested unchanged, and moving the mark point or the area to be tested of the sample to be tested into the first field of view of the first objective lens, then moving the sample to be tested up and down, and controlling the camera to collect a second sample image of the sample to be tested; and in response to the second sample image reaching the state of optimal contrast, or the sum of the grayscale values ​​of the sample image reaching a peak value, determining that the focusing of the sample to be tested is completed.

[0022] Furthermore, in some embodiments of the present invention, the semiconductor measurement method also includes the following steps: in response to the acquired control instruction indicating the detection of the defect size and / or trace width on the sample to be tested, controlling the wavelength selection unit to output the narrow-band illumination light of the multiple different central wavelengths in a time-sharing manner, and controlling the camera to respectively capture the third sample image under the illumination of each narrow-band illumination light; performing image feature extraction and target recognition on each third sample image under the illumination of the narrow-band illumination light to respectively determine the corresponding recognition results; and taking an average of the recognition results of each third sample image to determine the defect size and / or trace width on the sample to be tested.

[0023] Furthermore, the computer-readable storage medium provided in accordance with the third aspect of the present invention stores computer instructions, which, when executed by a processor, implement the semiconductor measurement method provided in accordance with the second aspect of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above features and advantages of the present invention will be better understood after reading the detailed description of the embodiments of the present disclosure in conjunction with the following drawings. In the drawings, the components are not necessarily drawn to scale, and components with similar related properties or characteristics may have the same or similar reference numerals.

[0025] FIG1 shows a schematic structural diagram of a semiconductor measurement system according to some embodiments of the present invention.

[0026] FIG2 is a schematic diagram showing an output spectrum of a wavelength selection unit according to some embodiments of the present invention.

[0027] FIG3 shows a schematic structural diagram of a Kohler illumination module according to some embodiments of the present invention.

[0028] FIG4 is a schematic diagram showing illumination light of a Köhler illumination module according to some embodiments of the present invention.

[0029] FIG. 5A is a schematic diagram illustrating non-correlated irradiance of a semiconductor measurement system according to some embodiments of the present invention.

[0030] FIG. 5B shows a non-correlated irradiance cross-sectional graph of a semiconductor metrology system according to some embodiments of the present invention.

[0031] FIG6 is a schematic flow chart showing a semiconductor measurement method according to some embodiments of the present invention.

[0032] FIG7 shows a schematic diagram of a sample image provided according to some embodiments of the present invention.

[0033] FIG8 shows a graph of grayscale values ​​of a charge coupled device image according to some embodiments of the present invention.

[0034] Description of the drawings:

[0035] 111 Light Source

[0036] 112 wavelength selection unit

[0037] 113 First lens

[0038] 114 Field stop

[0039] 115 Second lens

[0040] 1161, 1162 Aperture diaphragm

[0041] 117 Collimation Unit

[0042] 118 focusing units

[0043] 121 First Spectroscopic Unit

[0044] 122 Second Spectroscopic Unit

[0045] 123 First Objective

[0046] 124 Second objective lens

[0047] 125 Reflection Unit

[0048] 131 Spectrometer

[0049] 132 Camera

[0050] 701 No graphics area

[0051] 702 cathode area

[0052] 703 Insulation Trench

[0053] 704 Anode area DETAILED DESCRIPTION

[0054] The following specific embodiments illustrate the embodiments of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this embodiment. On the contrary, the purpose of introducing the invention in conjunction with the embodiment is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description.

[0055] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0056] Furthermore, the terms "upper," "lower," "left," "right," "top," "bottom," "horizontal," and "vertical" used in the following description should be understood to refer to the orientations depicted in that section and the accompanying drawings. These relative terms are used solely for convenience of description and do not necessarily imply that the devices described herein must be manufactured or operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0057] It will be understood that although the terms "first," "second," "third," etc. may be used herein to describe various components, regions, layers, and / or portions, these components, regions, layers, and / or portions should not be limited by these terms, and these terms are merely used to distinguish different components, regions, layers, and / or portions. Thus, a first component, region, layer, and / or portion discussed below may be referred to as a second component, region, layer, and / or portion without departing from some embodiments of the present invention.

[0058] As mentioned above, existing film thickness measurement equipment, due to limitations imposed by their optical systems or the diffraction limit of their light sources, mostly has a spot size larger than 30μm. This makes it difficult to measure film thicknesses below 30μm, and it also fails to detect defects in tiny structural features. Therefore, users who need both film thickness measurement and defect detection must purchase two separate devices, significantly increasing semiconductor processing costs.

[0059] In order to overcome the above-mentioned defects of the prior art, the present invention provides an improved semiconductor measurement system, a semiconductor measurement method and a computer-readable storage medium, which can perform large-area film thickness measurement, small-area film thickness measurement and microstructure detection respectively by simultaneously including a Köhler illumination module with a wavelength selection unit, a high-magnification first objective lens, a low-magnification second objective lens, a spectrometer and a camera, so as to realize "one-stop" measurement of various semiconductor parameters, thereby effectively reducing the economic cost of semiconductor measurement and improving the efficiency of semiconductor measurement.

[0060] In some non-limiting embodiments, the semiconductor measurement method provided in the second aspect of the present invention may be implemented based on the semiconductor measurement system provided in the first aspect of the present invention.

[0061] For details, please refer to Figures 1 to 4 and Figures 5A to 5B. Figure 1 shows a schematic diagram of the structure of a semiconductor measurement system provided according to some embodiments of the present invention. Figure 2 shows a schematic diagram of the output spectrum of a wavelength selection unit provided according to some embodiments of the present invention. Figure 3 shows a schematic diagram of the structure of a Köhler illumination module provided according to some embodiments of the present invention. Figure 4 shows a schematic diagram of the illumination light of a Köhler illumination module provided according to some embodiments of the present invention. Figure 5A shows a schematic diagram of the non-correlated irradiance of a semiconductor measurement system provided according to some embodiments of the present invention. Figure 5B shows a cross-sectional curve diagram of the non-correlated irradiance of a semiconductor measurement system provided according to some embodiments of the present invention.

[0062] In the embodiment shown in FIG1 , the semiconductor measurement system provided by the first aspect of the present invention includes a Köhler illumination module, an optical module, a detection module, a memory, and a controller. The Köhler illumination module is configured to provide narrowband illumination light with multiple different central wavelengths. The optical module is configured to focus the illumination light onto the surface of the test area of ​​the sample to be tested and couple the reflected light generated by the sample to a back-end detection module. The sample to be tested includes, but is not limited to, wafers, masks used for chip processing, LCD and OLED displays, and other semiconductor devices such as masks required for their processing. The detection module is configured to indicate, based on the input reflected light, the average film thickness within a first region of the sample surface greater than a preset size, or the film thickness and / or microstructure within a second region of the sample surface less than or equal to a preset size. The memory includes, but is not limited to, the computer-readable storage medium provided by the third aspect of the present invention, storing computer instructions. The controller is connected to the memory and configured to execute the computer instructions stored in the memory to implement the semiconductor measurement method provided by the second aspect of the present invention.

[0063] Specifically, the Köhler illumination module includes, in sequence, a light source 111, a wavelength selection unit 112, a first lens 113, a field stop 114, a second lens 115, aperture stops 1161 and 1162, a first objective lens 123, and a second objective lens 124. Here, the light source 111 is a broad-spectrum light source selected from at least one of an LDLS, a xenon lamp, an LED, and a tuned laser, configured to output broad-spectrum light. The wavelength selection unit 112 is configured to filter out narrow-band illumination light of various central wavelengths from the original light provided by the light source 111 in a time-sharing manner, in accordance with instructions from a controller. The surfaces of the first lens 113 and / or the second lens 115 are coated with an antireflection coating. The first lens 113 and the second lens 115 have different focal lengths, which are used to control the magnification of the object image. The field stop 114 is an adjustable stop, configured to adjust the size of the illumination area of ​​the narrow-band illumination light on the surface of the sample to be measured, to adapt to the sizes of the first and second areas, respectively. Aperture diaphragms 1161 and 1162 are adjustable diaphragms used to adjust the brightness of the narrowband illumination light on the surface of the sample to be measured, thereby adapting the data acquisition sensitivity and overexposure range of spectrometer 131 and camera 132, respectively. Aperture diaphragms 1161 and 1162 are conjugate with the plane of light source 111, while field diaphragm 114 is conjugate with the sample plane at the rear end where the sample to be measured is located. These diaphragms cooperate to output multiple narrowband illumination light rays with different fields of view in parallel to the first and second objective lenses 123 and 124 at the rear end.

[0064] Furthermore, the wavelength selection unit 112 includes a color wheel with a wheel-shaped support equipped with a through-hole and multiple narrowband filters of different wavelength ranges. The through-hole is used to output broad-spectrum light from a broad-spectrum light source to the spectrometer 131. The narrowband filters are designed to sequentially move into the transmission path of the broad-spectrum light as the wheel-shaped support rotates, providing a variety of narrowband illumination lights with different central wavelengths to the camera 132 in a time-sharing manner. This allows the addition of neutral density filters to control light intensity, enabling the semiconductor measurement system to achieve an ultra-high wavelength resolution of 3nm.

[0065] Specifically, as shown in FIG2 , after the original broad-spectrum light provided by the light source 111 passes through the wavelength selection unit 112, the spectrometer 131 receives the number of photons (cnts) of each wavelength and performs test analysis. A monochromatic light spectrum of a narrow-band illumination light can be obtained at 417.6 nm, with a half-peak width of 3.9 nm and a center wavelength error of 0.4 nm.

[0066] Those skilled in the art will understand that the above-mentioned embodiment of using a color wheel for wavelength selection is only a non-limiting implementation method provided by the present invention, which is intended to clearly illustrate the main concept of the present invention and provide some specific solutions that are convenient for the public to implement, rather than to limit the scope of protection of the present invention.

[0067] Optionally, in other embodiments, the wavelength selection unit 112 may also use a monochromator, a wavelength selector and other devices to achieve the same wavelength selection effect.

[0068] Furthermore, in the embodiment shown in FIG3 , the first lens 113 can be composed of a first concave transmissive element and a first convex transmissive element arranged closely in sequence. Specifically, the refractive index of the first concave transmissive element can be 1.747939, and its dispersion coefficient can be 44.62. The refractive index of the first convex transmissive element can be 1.812632, and its dispersion coefficient can be 25.25. The light-emitting surface of the first concave transmissive element can be in close contact with the light-entering surface of the first convex transmissive element to achieve a focal length of 14.4 mm. Similarly, the second lens 115 can be composed of a second convex transmissive element and a second concave transmissive element arranged closely in sequence. Specifically, the refractive index of the second convex transmissive element can be 1.812632, and its dispersion coefficient can be 25.25. The refractive index of the second concave transmissive element can be 1.594869, and its dispersion coefficient can be 67.96. The light-emitting surface of the second convex element can be close to the light-entering surface of the second concave element to obtain a focal length of 72 mm, and cooperate with the first lens 113, the field stop 114 and the corresponding aperture stops 1161 and 1162 to output a 5x magnified image of the light source 111.

[0069] In this way, as shown in FIG4 , the Köhler illumination module can output multiple narrow-band illumination lights in different fields of view in parallel to the rear end, so as to take into account the illumination uniformity required in each field of view.

[0070] Furthermore, as shown in Figure 5A, the Köhler illumination module can form a circular illumination surface with uniform irradiance in the center of the field of view. As shown in Figure 5B, the non-correlated irradiance values ​​within the central circular illumination surface are nearly horizontal. Thus, the combination of the first lens 113 and the second lens 115 in the Köhler illumination module can simultaneously achieve an illumination uniformity of 95% for both the high-magnification and low-magnification fields of view, achieving highly uniform illumination.

[0071] Those skilled in the art will understand that the specific parameters of the Köhler illumination module involved in the above-mentioned Figures 1 to 4 and Figures 5A to 5B are merely a non-limiting implementation method provided by the present invention, which is intended to clearly demonstrate the main concept of the present invention and provide some specific solutions that are convenient for the public to implement, rather than to limit the scope of protection of the present invention.

[0072] Optionally, in other embodiments, those skilled in the art may also configure different optical element parameters according to actual needs to obtain corresponding light source amplification effects, which will not be described in detail here.

[0073] Furthermore, referring to FIG. 1 , in some embodiments, the Köhler illumination module may further include a collimating unit 117 and a focusing unit 118. The collimating unit 117 is disposed between the light source 111 and the wavelength selection unit 112 and utilizes a large-focal-length 90° off-axis parabolic mirror to fold the optical path and direct the divergent original light provided by the light source 111 into the wavelength selection unit 112 in parallel. The focusing unit 118 is disposed between the wavelength selection unit 112 and the first lens 113 and utilizes a large-focal-length 90° off-axis parabolic mirror to fold the optical path and direct the parallel light output from the wavelength selection unit 112 into the first lens 113.

[0074] Those skilled in the art will appreciate that the above-mentioned embodiment of the 90° off-axis parabolic mirror is only a non-limiting implementation method provided by the present invention, which is intended to clearly illustrate the main concept of the present invention and provide some specific solutions that are convenient for the public to implement, rather than to limit the scope of protection of the present invention.

[0075] Alternatively, in other embodiments, the collimating unit 117 may also be configured to use optical elements such as a collimator, a parabolic mirror, or a collimating lens to achieve the same effect of collimating the light. Similarly, the focusing unit 118 may also be configured to use optical elements such as a parabolic mirror or a converging lens to achieve the same effect of focusing the light.

[0076] In addition, in the embodiment shown in FIG1 , the optical module may further include a first spectroscopic unit 121, a second spectroscopic unit 122, and a reflective unit 125. Here, the first spectroscopic unit 121 and the second spectroscopic unit 122 are both selected from spectroscopes and / or spectroscopic prisms, and are preferably spectroscopic prisms to reduce astigmatism and improve imaging quality. The first spectroscopic unit 121 is used to first transmit the narrowband illumination light provided by the Köhler illumination module directly to the first objective lens 123, or to the second objective lens 124 via the reflective unit 125, so as to uniformly illuminate the sample to be tested on the object side (e.g., below) via the first objective lens 123 or the second objective lens 124, and then transmit the reflected light generated by the sample to be tested to the second spectroscopic unit 122 on the image side (e.g., above). The second spectroscopic unit 122 is used to transmit the reflected light to the spectrometer 131 and camera 132 at the rear end, respectively.

[0077] Those skilled in the art will understand that the reflection unit 125 shown in Figure 1 is only a non-limiting embodiment provided by the present invention, which is intended to make the first objective lens 123 and the second objective lens 124 have the same orientation, so as to facilitate the user to simply move the test area of ​​the sample to be tested to the field of view of the first objective lens 123 or the second objective lens 124 by moving the sample to be tested laterally.

[0078] Optionally, in other embodiments, those skilled in the art may also directly set the second objective lens 124 laterally to the lateral output end of the first spectroscopic unit 121, and adjust the placement angle of the sample to be tested to collect the reflected light generated by the sample to be tested through the second objective lens 124.

[0079] Furthermore, in some embodiments, the first objective lens 123 can be a high-magnification objective lens with a small focal length and a large NA. The camera 132 can cooperate with the high-magnification objective lens to magnify the microscopic features of the sample to be tested up to 50 times to achieve a high-resolution sampling of 15 pixels / μm. In addition, the second objective lens can be a low-magnification objective lens with a large focal length and a small NA. The spectrometer 131 and the camera 132 can cooperate with the low-magnification objective lens to effectively expand the field of view of the semiconductor measurement system, so as to quickly find the area to be tested on the surface of the sample to be tested and quickly perform average film thickness measurement in a first area larger than a preset size.

[0080] In addition, in some embodiments, the detection module includes a spectrometer 131 and a camera 132. The spectrometer 131 is connected to the second spectrometer unit 122 via a first tube lens 133, and is used to collect spectral information of the reflected light provided by the second spectrometer unit 122 to indicate the average film thickness in a first area of ​​the surface of the sample to be tested that is larger than a preset size. The camera 132 is connected to the second spectrometer unit 122 via a second tube lens 134, and is used to generate a corresponding sample image based on the reflected light transmitted to its detection surface, indicating the film thickness and / or microstructure in a second area of ​​the surface of the sample to be tested that is smaller than or equal to the preset size. Furthermore, the camera 132 can be a CCD camera or a CMOS camera to achieve a resolution of 0.6μm.

[0081] Furthermore, as shown in FIG1 , in some embodiments of the present invention, to meet the requirements of an autofocus function, the semiconductor measurement system may further preferably include a moving stage 141. The moving stage 141 is configured to carry and move the sample to be measured laterally between a first position below the first objective lens 123 and a second position below the second objective lens 124, and to move longitudinally in a vertical direction toward or away from the first objective lens 123 and the second objective lens 124.

[0082] In this way, the above-mentioned semiconductor measurement system provided by the first aspect of the present invention is equipped with a spectrometer 131 and a camera 132 at the same time, so as to adapt to the measurement requirements of the average film thickness of a first area larger than a preset size, the film thickness and / or microstructure in a second area smaller than or equal to a preset size, and the functional requirement of automatic focusing on the sample to be measured, so as to realize "one-stop" measurement of various semiconductor parameters, thereby effectively reducing the economic cost of semiconductor measurement and improving the efficiency of semiconductor measurement.

[0083] The following describes the operating principles of the semiconductor measurement system described above, using examples of semiconductor measurement methods. Those skilled in the art will appreciate that these examples of semiconductor measurement methods are merely non-limiting implementations of the present invention, intended to clearly demonstrate the main concepts of the present invention and provide specific solutions that facilitate implementation by the public. They do not limit the full functionality or operation of the semiconductor measurement system. Similarly, the semiconductor measurement system is merely a non-limiting implementation of the present invention and does not restrict the execution entities or execution order of the steps in these semiconductor measurement methods.

[0084] Please refer to Figures 6 to 8. Figure 6 shows a flow chart of a semiconductor measurement method provided according to some embodiments of the present invention. Figure 7 shows a schematic diagram of a sample image provided according to some embodiments of the present invention. Figure 8 shows a curve chart of the image grayscale value of a charge coupled device provided according to some embodiments of the present invention.

[0085] As shown in FIG6 , during the measurement process, the semiconductor measurement system may first receive a control command input by a user. In some embodiments, in response to a first control command indicating that the area to be measured is larger than a predetermined size (e.g., 30 μm), the measurement system may determine that the area to be measured is a first area and enter a first detection mode for large areas. This mode first provides a broad spectrum of light to the surface of the sample to be measured below the second objective lens 124 via the wavelength selection unit 112, and then determines the average film thickness within the first area based on the spectral information collected by the spectrometer 131.

[0086] In other embodiments, in response to a first control instruction indicating that the area to be measured is less than or equal to a preset size (e.g., 30 μm), the measurement system may determine that the area to be measured is a second area and enter a second mode for small-size areas, thereby providing, via the wavelength selection unit 112, a variety of narrowband illumination lights with different central wavelengths to the surface of the sample to be measured below the first objective lens in a time-sharing manner. Simultaneously, the measurement system may capture, via the camera 132, sample images of the corresponding second area under each narrowband illumination light. As shown in FIG7 , the sample image can be divided into a non-patterned area 701, a cathode area 702, an insulating channel 703, and an anode area 704.

[0087] The semiconductor metrology system then analyzes each sample image to determine its relative intensity and / or relative reflectivity values, and uses these values ​​to fit relative intensity and / or relative reflectivity curves for the second region at each center wavelength. The metrology system then inputs the fitted relative intensity and / or relative reflectivity curves into a pre-trained regression analysis model, and uses this regression analysis model to perform regression analysis on the relative intensity and / or relative reflectivity curves to determine the film thickness on the surface of the second region.

[0088] Furthermore, the above-mentioned regression analysis model can be obtained by training multiple sets of sample data of relative light intensity curves and / or relative reflectivity curves of multiple standard samples with known film thicknesses at multiple different center wavelengths. Specifically, in the process of training the above-mentioned regression analysis model, technicians can first obtain multiple sets of sample data of relative light intensity curves and / or relative reflectivity curves of multiple standard samples with known film thicknesses at multiple different center wavelengths, and construct a regression analysis model based on the Levenberg-Marquardt algorithm. Afterwards, the measurement system can input the relative light intensity curves and / or relative reflectivity curves of each set of sample data into the above-mentioned regression analysis model, and correct the learning parameters of the regression analysis model according to the corresponding film thickness to obtain a fully trained regression analysis model.

[0089] Those skilled in the art will understand that the embodiment of obtaining the first control instruction and measuring the size of the area to be measured as shown in Figure 6 is only a non-limiting implementation method provided by the present invention, which is intended to clearly demonstrate the main concept of the present invention and provide some specific solutions that are convenient for the public to implement, rather than to limit the scope of protection of the present invention.

[0090] Optionally, in other embodiments, in response to receiving a second control instruction instructing detection of defect size and / or trace width on a sample to be tested, the semiconductor metrology system may further control the wavelength selection unit 112 to time-share output narrowband illumination light of multiple different central wavelengths, and control the camera 132 to capture a third sample image illuminated by each narrowband illumination light. The metrology system may then utilize a pre-trained image recognition model and / or template comparison model to perform image feature extraction and target recognition on each third sample image illuminated by the narrowband illumination light, thereby determining corresponding recognition results. The recognition results for each third sample image may then be averaged to determine the defect size and / or trace width on the sample to be tested.

[0091] Furthermore, when detecting the defect size and / or trace width on the sample to be tested, the measurement system can preferably first use the low-magnification second objective lens 124 to perform preliminary defect detection / preliminary line width detection, and then use the high-magnification first objective lens 123 to review or verify after the detection result exceeds the preset threshold, so as to further improve the detection accuracy of the defect size and / or trace width.

[0092] Optionally, in other embodiments, in response to obtaining a second control instruction instructing to execute the autofocus function, the semiconductor measurement system can also control the moving stage 141 to first move the marking point or the area to be tested of the sample to be tested into the second field of view of the second objective lens 124, and then move the sample to be tested up and down, and control the camera 132 to capture the first sample image of the sample to be tested.

[0093] Afterwards, in response to the first sample image reaching the state of optimal contrast, the semiconductor measurement system can control the moving stage 141 to first keep the up and down positions of the sample to be tested unchanged, and move the marking point or the area to be tested of the sample to be tested into the first field of view of the first objective lens 123, and then move the sample to be tested up and down, and control the camera 132 to collect the second sample image of the sample to be tested, so as to achieve the state of optimal contrast in the second sample image, or the sum of the grayscale values ​​of the second sample image reaches a peak value, and determine that the focus on the sample to be tested is completed.

[0094] Furthermore, in some embodiments, since the spectrometer 131 has a lower amount of light intensity calculation data and a faster light intensity calculation response, in the process of moving the sample to be tested up and down, the semiconductor measurement system can first control the spectrometer 131 to detect the intensity of the reflected light, and then after the intensity of the reflected light collected by the spectrometer 131 reaches a peak, switch the camera 132 to collect the first sample image or the second sample image of the sample to be tested, and use the contrast of the charge-coupled device (CCD) of the camera 132 or the total grayscale of the image as the focus plane criterion as described above to determine the optimal contrast position of the sample to be tested, thereby improving the autofocus efficiency of the measurement system.

[0095] As shown in Figure 8, in the grayscale image of the CCD of camera 132, 20 pixels correspond to 1.2 μm of the sample. Therefore, the semiconductor measurement system provided by the first aspect of the present invention can achieve a resolution of 60 nm / pixel to obtain extremely high imaging quality.

[0096] Those skilled in the art will understand that the above-mentioned embodiment of online adjustment of the movable stage 141 to determine the optimal contrast position of the sample to be tested is only a non-limiting implementation method provided by the present invention, which is intended to clearly demonstrate the main concept of the present invention and provide some specific solutions that are convenient for the public to implement, rather than to limit the scope of protection of the present invention.

[0097] Preferably, in other embodiments, technicians can also calibrate using a reference film with known characteristics to determine the distance between the peak light intensity position of the spectrometer 131 and the optimal contrast position or the peak grayscale value position of the camera 132, and pre-store this distance in the measurement system. In this way, when the sample to be measured is moved up and down, in response to the reflected light intensity reaching a peak, the measurement system can directly determine the focus position of the sample to be measured based on the current position and this distance, thereby further improving the measurement system's autofocus efficiency.

[0098] In summary, the semiconductor measurement system, semiconductor measurement method, and computer-readable storage medium provided by the present invention can all perform large-area film thickness measurement, small-area film thickness measurement, and microstructure detection by simultaneously including a Köhler illumination module with a wavelength selection unit, a high-magnification first objective lens, a low-magnification second objective lens, a spectrometer, and a camera, thereby achieving "one-stop" measurement of various semiconductor parameters, thereby effectively reducing the economic cost of semiconductor measurement and improving the efficiency of semiconductor measurement.

[0099] Although the above methods are illustrated and described as a series of acts for simplicity of explanation, it is to be understood and appreciated that these methods are not limited by the order of the acts, as some acts may occur in a different order and / or concurrently with other acts from those illustrated and described herein or not illustrated and described herein but understandable to those skilled in the art according to one or more embodiments.

[0100] Those skilled in the art will appreciate that information, signals, and data may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips cited throughout the foregoing description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0101] Those skilled in the art will further appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the embodiments disclosed herein can be implemented as electronic hardware, computer software, or a combination of the two. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. A skilled person may implement the described functionality in different ways for each specific application, but such implementation decisions should not be interpreted as resulting in a departure from the scope of the present invention.

[0102] The preceding description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A semiconductor measurement system, characterized in that: include: A Köhler illumination module, comprising, in sequence, a broad-spectrum light source, a wavelength selection unit, a first lens, a field stop, a second lens, an aperture stop, and an objective lens, wherein the objective lens comprises a high-magnification first objective lens and a low-magnification second objective lens, the wavelength selection unit being configured to at least time-share filter out a plurality of narrow-band illumination light rays having different central wavelengths from the original light provided by the broad-spectrum light source, the aperture stop being conjugate to the plane of the broad-spectrum light source, and the field stop being conjugate to the sample plane at the rear end where the sample to be measured is located, and configured to output a plurality of narrow-band illumination light rays having different fields of view in parallel to the first objective lens and the second objective lens; An optical module, comprising a first spectroscopic unit and a second spectroscopic unit, wherein the first spectroscopic unit is used to first transmit the narrowband illumination light provided by the Köhler illumination module to the first objective lens and the second objective lens, so as to uniformly illuminate the sample to be tested on the object side thereof through the first objective lens or the second objective lens, and then transmit the reflected light generated by the sample to be tested to the second spectroscopic unit on the image side, so as to transmit the reflected light to the spectrometer and camera at the rear end respectively through the second spectroscopic unit; a detection module, comprising the spectrometer and the camera, wherein the spectrometer is configured to collect spectral information of the reflected light provided by the second spectroscopic unit to indicate an average film thickness in a first area of ​​the surface of the sample to be tested that is larger than a preset size, and the camera is configured to generate a corresponding sample image based on the reflected light transmitted to its detection surface to indicate the film thickness and / or microstructure in a second area of ​​the surface of the sample to be tested that is smaller than or equal to the preset size; and The controller is configured to: obtain a first control instruction indicating the size of the area to be measured; in response to the first control instruction indicating that the area to be measured is less than or equal to the preset size, determine that the area to be measured is the second area, thereby providing a plurality of narrow-band illumination lights of different central wavelengths to the surface of the sample to be measured on the object side of the first objective lens via the wavelength selection unit in a time-sharing manner, and respectively collecting sample images of the corresponding second area under each of the narrow-band illumination lights via the camera to determine the film thickness on the surface of the second area; and in response to the first control instruction indicating that the area to be measured is larger than the preset size, determine that the area to be measured is the first area, thereby providing wide-spectrum light to the surface of the sample to be measured on the object side of the second objective lens via the wavelength selection unit, and determining the average film thickness in the first area based on the spectral information collected by the spectrometer.

2. The semiconductor measurement system according to claim 1, wherein: The broad spectrum light source is selected from at least one of LDLS, xenon lamp, LED, tuned laser, and / or The wavelength selection unit includes a color wheel, a wheel-shaped support having a through hole and a plurality of narrow-band filters of different wavelength ranges, the through hole being used to output the broad-spectrum light provided by the broad-spectrum light source to the spectrometer, and each narrow-band filter being used to move sequentially to the transmission path of the broad-spectrum light as the wheel-shaped support rotates, so as to provide the camera with the plurality of narrow-band illumination lights of different central wavelengths in a time-sharing manner, and / or The surface of the first lens and / or the second lens is coated with an antireflection film, and / or The field diaphragm is an adjustable diaphragm for adjusting the size of the illumination area of ​​the narrow-band illumination light on the surface of the sample to be measured to respectively adapt to the size of the first area and the second area, and / or The aperture diaphragm is an adjustable diaphragm for adjusting the illumination brightness of the narrow-band illumination light on the surface of the sample to be measured, so as to adapt the data acquisition sensitivity and overexposure range of the spectrometer and the camera respectively.

3. The semiconductor measurement system according to claim 2, wherein: The Kohler illumination module further includes a collimating unit and a focusing unit, wherein: The collimating unit is provided between the broad spectrum light source and the wavelength selection unit, and uses a 90° off-axis parabolic mirror with a large focal length to fold the optical path and input the divergent original light provided by the broad spectrum light source into the wavelength selection unit in parallel. The focusing unit is arranged between the wavelength selection unit and the first lens, and uses a 90° off-axis parabolic mirror with a large focal length to fold the light path and focus the parallel light output by the wavelength selection unit onto the first lens.

4. The semiconductor measurement system according to claim 2, wherein: The first lens has a focal length of 14.4 mm and includes a first concave lens element with a refractive index of 1.747939 and an Abbe number of 44.62, and a first convex lens element with a refractive index of 1.812632 and an Abbe number of 25.25, wherein the light-emitting surface of the first concave lens element is in close contact with the light-entering surface of the first convex lens element. The focal length of the second lens is 72 mm, and it includes a second convex element with a refractive index of 1.812632 and a chromatic aberration coefficient of 25.25, and a second concave element with a refractive index of 1.594869 and a chromatic aberration coefficient of 67.

96. The light-emitting surface of the second convex element is in close contact with the light-entering surface of the second concave element to cooperate with the first lens, the field stop and the aperture stop to output a magnified image of the wide-spectrum light source.

5. The semiconductor measurement system according to claim 1, wherein: The controller is further configured to: Determining a relative light intensity value and / or a relative reflectivity value of each of the sample images to fit a relative light intensity curve and / or a relative reflectivity curve of the second region with respect to each of the central wavelengths; as well as According to a pre-trained regression analysis model, regression analysis is performed on the relative light intensity curve and / or the relative reflectivity curve to determine the film thickness on the surface of the second region.

6. The semiconductor measurement system according to claim 5, wherein: The steps of training the regression analysis model include: respectively acquiring a plurality of groups of sample data of relative intensity curves and / or relative reflectivity curves of a plurality of standard samples of known film thicknesses at a plurality of different central wavelengths; Constructing a regression analysis model to be trained; and The relative light intensity curve and / or relative reflectivity curve of each group of sample data are respectively input into the regression analysis model, and the learning parameters of the regression analysis model are corrected according to the corresponding film thickness to obtain the regression analysis model that completes the training.

7. The semiconductor measurement system according to claim 5, wherein: Also includes: The movable stage is used for carrying and moving the sample to be tested laterally between a first position of the first objective lens and a second position of the second objective lens, and moving longitudinally along a vertical direction close to or away from the first objective lens and the second objective lens.

8. The semiconductor measurement system according to claim 7, wherein: The controller is further configured to: obtaining a second control instruction indicating a function type; In response to the second control instruction instructing to execute the autofocus function, controlling the moving stage to first move the marked point or the area to be tested of the sample to be tested into the second field of view of the second objective lens, then moving the sample to be tested up and down, and controlling the camera to capture a first sample image of the sample to be tested; In response to the first sample image reaching an optimal contrast state, controlling the moving stage to first maintain the vertical position of the sample to be tested unchanged, and moving the marked point or the area to be tested of the sample to be tested into the first field of view of the first objective lens, then moving the sample to be tested up and down, and controlling the camera to capture a second sample image of the sample to be tested; as well as In response to the second sample image reaching an optimal contrast state, or the sum of the grayscale values ​​of the second sample image reaching a peak value, it is determined that the focusing of the sample to be measured is completed.

9. The semiconductor measurement system according to claim 8, wherein: The controller is further configured to: In the process of moving the sample to be tested up and down, first controlling the spectrometer to detect the intensity of the reflected light; and In response to the light intensity of the reflected light reaching a peak value, the camera is controlled to capture the first sample image or the second sample image of the sample to be tested.

10. The semiconductor measurement system according to claim 8, wherein: The controller is further configured to: In the process of moving the sample to be tested up and down, controlling the spectrometer to detect the intensity of the reflected light; and In response to the light intensity of the reflected light reaching a peak, the focus position of the sample to be tested is determined according to the current position and the distance between the light intensity peak position of the spectrometer and the optimal contrast position or the gray value sum peak position of the camera.

11. The semiconductor measurement system according to claim 5, wherein: The microstructure includes defects and / or traces located in the semiconductor device, and the controller is further configured to: obtaining a second control instruction indicating a function type; In response to the second control instruction instructing to detect the defect size and / or trace width on the sample to be tested, controlling the wavelength selection unit to output the multiple narrow-band illumination lights with different central wavelengths in a time-sharing manner, and controlling the camera to respectively capture a third sample image illuminated by each of the narrow-band illumination lights; performing image feature extraction and target recognition on the third sample images under the illumination of the narrow-band illumination light, respectively, to determine corresponding recognition results; as well as An average value is taken for the recognition results of each of the third sample images to determine the defect size and / or trace width on the sample to be tested.

12. A semiconductor measurement method, characterized in that: The following steps are involved: Get control instructions; In response to the acquired control instruction indicating film thickness detection, and the area to be measured is larger than a preset size, determining that the area to be measured is a first area, thereby providing a wide spectrum light to the surface of the sample to be measured on the object side of the second objective lens of the semiconductor measurement system according to any one of claims 1 to 11, and determining the average film thickness in the first area based on the spectral information collected by the spectrometer; as well as In response to the acquired control instruction indicating film thickness detection, and the area to be measured is smaller than or equal to the preset size, the area to be measured is determined to be the second area, thereby providing a plurality of narrow-band illumination lights with different central wavelengths to the surface of the sample to be measured on the object side of the first objective lens in a time-sharing manner via the wavelength selection unit, and respectively capturing sample images of the corresponding second area under each of the narrow-band illumination lights via the camera in the semiconductor measurement system, and then performing regression analysis based on each of the sample images to determine the film thickness on the surface of the second area.

13. The semiconductor measurement method according to claim 12, wherein: The following steps are also included: In response to the acquired control instruction, an autofocus function is executed, firstly the marked point or the area to be measured of the sample to be measured is moved into the second field of view of the second objective lens, then the sample to be measured is moved up and down, and the camera is controlled to capture a first sample image of the sample to be measured; In response to the state in which the first sample image reaches the best contrast, the upper and lower positions of the sample to be tested are kept unchanged, and the marking point or the area to be tested of the sample to be tested is moved to the first position of the first objective lens. within the field of view, moving the sample to be tested up and down, and controlling the camera to capture a second sample image of the sample to be tested; as well as In response to the second sample image reaching an optimal contrast state, or the total grayscale value of the sample image reaching a peak value, it is determined that the focusing of the sample to be measured is completed.

14. The semiconductor measurement method according to claim 12, wherein: The following steps are also included: In response to the acquired control instruction instructing to detect the defect size and / or trace width on the sample to be tested, controlling the wavelength selection unit to output the multiple narrow-band illumination lights of different central wavelengths in a time-sharing manner, and controlling the camera to respectively capture a third sample image illuminated by each of the narrow-band illumination lights; performing image feature extraction and target recognition on the third sample images under the illumination of the narrow-band illumination light, respectively, to determine corresponding recognition results; as well as An average value is taken for the recognition results of each of the third sample images to determine the defect size and / or trace width on the sample to be tested.

15. A computer-readable storage medium having computer instructions stored thereon, characterized in that: When the computer instructions are executed by a processor, the measurement method according to any one of claims 12 to 14 is implemented.

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