Monitoring system and its monitoring method, optical system and its working method

Abstract

The present disclosure relates to a monitoring system and a monitoring method thereof, an optical system and a working method thereof. The monitoring system includes a first optical component, a second optical component and an adjustment module. The adjustment module is used to synchronously adjust the rotation angles of the first mirror and the second mirror relative to the normal plane of the sample surface, so that the first illumination light reflected by the sample at points with different surface heights perpendicular to the surface and at the same points along the sample surface forms a first signal light and is collected at the same position of the first detector. The detection accuracy of the sample surface is improved.

Description

Technical Field

[0001] The present disclosure relates to the field of detection technologies, and particularly to a monitoring system and its monitoring method, an optical system and its working method. Background Art

[0002] Due to the characteristics of complex processes, numerous procedures, and small device sizes in the semiconductor industry, wafers are extremely prone to defects during the production process. These defects not only seriously affect the chip performance but also increase costs. Therefore, in all processes of semiconductor production, the detection link is crucial.

[0003] During the wafer detection process, it is often necessary to detect surface defects of the wafer by means of illumination. During the defect detection process, the height of the wafer surface changes, that is, the wafer surface offsets in the direction perpendicular to the wafer surface, resulting in the offset of the measurement points for detecting defects in the direction parallel to the wafer surface, thereby causing deviation in the detected defect positions and reducing the detection accuracy. Summary of the Invention

[0004] The present disclosure provides a monitoring system and its monitoring method, an optical system and its working method to solve the problem of how to improve the detection accuracy.

[0005] In a first aspect, the present disclosure provides a monitoring system, including: a first optical component including a first mirror, the first mirror being configured to reflect a first illumination light and make the first illumination light obliquely incident on a sample surface, and the sample surface reflecting the first illumination light to form a first signal light; a second optical component including a second mirror, an imaging component, and a first detector, the imaging component being configured to image the sample surface to the first detector using the first signal light, the first detector being configured to obtain a detection image of the sample surface according to the first signal light and form a light spot on a photosensitive surface of the first detector, and the second mirror being configured to make the light spot formed by the first signal light reflected from the sample surface at a preset calibration position be at a preset position on the photosensitive surface of the first detector; an adjustment module configured to synchronously adjust the rotation angles of the first mirror and the second mirror relative to a normal plane of the sample surface, so that the first illumination light reflected from points on the sample surface with different heights perpendicular to the surface and the same along the sample surface forms a first signal light that is collected at the same position of the first detector.

[0006] Optionally, the adjustment module is configured to make the incident position of the first illumination light on the sample have a first change amount along a direction parallel to a converging surface, and a conjugate point of the light spot of the first detector in the object space has a second change amount along a direction parallel to the conjugate plane of the photosensitive surface of the first detector in the object space, and the first change amount is equal to the second change amount.

[0007] Optionally, the second reflector is located in the optical path between the imaging component and the first detector. The rotation direction of the first reflector is opposite to that of the second reflector. The second change amount is (d 3* ∠2) / M or (d 3* tan∠2) / M, where d 3 is the distance between the second reflector and the first detector, ∠2 is the rotation angle of the second reflector, and M is the magnification of the imaging component; or, the second reflector is located in the optical path between the imaging component and the sample. The rotation direction of the first reflector is opposite to that of the second reflector. The second change amount is d 2 *∠2 or d 2* tan∠2; d 2 is the distance between the second reflector and the object-side focal plane of the imaging component; or, the imaging component includes a first collimator and a second focusing mirror. The first collimator is used to collimate the first signal light, and the second focusing mirror is used to focus the first signal light; the second reflector is located in the optical path between the first collimator and the second focusing mirror; the rotation direction of the first reflector is opposite to that of the second reflector; the second change amount is f 2 *tan∠2 or f 2 *∠2, where f 2 is the focal length of the first collimator.

[0008] Optionally, the first optical component further includes a first focusing mirror for focusing the first illumination light; the first reflector and the first focusing mirror are arranged along the incident direction of the first illumination light, and the first illumination light is incident on the first focusing mirror in parallel; the first change amount is f 1 *tan∠1 or f 1 *∠1; ∠1 is the rotation angle of the first reflector, and f 1 is the focal length of the first focusing mirror; or, the first focusing mirror and the first reflector are arranged along the incident direction of the first illumination light, and the first change amount is d 1 *tan∠1, or d 1 *∠1, where d 1 is the distance between the first reflector and the converging surface of the first illumination light.

[0009] Optionally, the imaging component includes a first collimator and a second focusing mirror. The first detector is located at the rear focal plane of the second focusing mirror; the first reflector and the first focusing mirror are arranged along the incident direction of the first illumination light; the second reflector is located between the first collimator and the second focusing mirror; the first illumination light reflected by the first reflector is parallel light; the first change amount is f 1*tan ∠1 or f 1 *∠1, and the second change amount is f 2 *tan ∠2 or f 2 *∠2.

[0010] Optionally, the focal length of the first focusing mirror is equal to the focal length of the first collimating mirror; the adjustment directions of the first reflecting mirror and the second reflecting mirror are opposite, and the adjustment amounts are the same.

[0011] Optionally, the optical path from the first reflecting mirror to the sample surface is symmetric with respect to the normal plane of the sample surface to the optical path from the second reflecting mirror to the sample surface.

[0012] Optionally, it further includes: a control system for judging whether the light spot deviates from a preset position according to the detection image; if so, the control system controls the adjustment module to synchronously adjust the rotation angles of the first reflecting mirror and the second reflecting mirror relative to the normal plane of the sample surface.

[0013] In a second aspect, the present disclosure provides a monitoring method applied to the monitoring system as described in the first aspect, including: reflecting the first illumination light through the first reflecting mirror and making the first illumination light incident on the sample surface, and the sample surface reflects the first illumination light to form a first signal light; acquiring a detection image of the sample surface through a second optical component; performing monitoring processing on the sample according to the detection image, and the monitoring processing includes: if the light spot deviates from the preset position, synchronously adjusting the rotation angles of the first reflecting mirror and the second reflecting mirror relative to the normal plane of the sample surface through an adjustment module, so that the first illumination light reflected by the sample at points with different heights perpendicular to the surface and along the same point on the sample surface forms a first signal light to be collected at the same position of the first detector.

[0014] Optionally, performing monitoring processing on the sample according to the detection image includes: judging whether the light spot deviates from the preset position according to the detection image; if the light spot deviates from the preset position, determining the rotation directions of the first reflecting mirror and the second reflecting mirror according to the deviation direction of the light spot from the preset position, and synchronously adjusting the rotation angles of the first reflecting mirror and the second reflecting mirror relative to the normal plane of the sample surface until the light spot is at the preset position.

[0015] Optionally, there are no reflecting elements between the first reflector and the sample, and there are no reflecting elements between the second reflector and the sample surface; or, there are an even number of reflecting elements between the first reflector and the sample, and there are an even number of reflecting elements between the second reflector and the sample surface; synchronously adjusting, by the adjustment module, the rotation angles of the first reflector and the second reflector relative to the normal plane of the sample surface includes: synchronously adjusting, by the adjustment module, the first reflector and the second reflector to rotate in opposite directions relative to the normal plane of the sample surface.

[0016] Optionally, synchronously adjusting, by the adjustment module, the rotation angles of the first reflector and the second reflector relative to the normal plane of the sample surface further includes: adjusting, by the adjustment module, the first reflector so that the incident position of the first illumination light on the sample has a first change amount parallel to the converging surface, and adjusting the second reflector so that the conjugate point of the spot of the first detector in the object space has a second change amount parallel to the photosensitive surface of the first detector in the conjugate plane in the object space, and the first change amount is equal to the second change amount.

[0017] Optionally, if the optical path from the first reflector to the sample surface is symmetric with respect to the normal plane of the sample surface to the optical path from the second reflector to the sample surface; or, the imaging assembly includes a first collimator and a second focusing lens, and the first detector is located at the rear focal plane of the second focusing lens; the first reflector and the first focusing lens are arranged along the incident direction of the first illumination light; the second reflector is located between the first collimator and the second focusing lens; the first illumination light reflected by the first reflector is parallel light, and the focal length of the first focusing lens is equal to the focal length of the first collimator; adjusting, by the adjustment module, the first reflector so that the incident position of the first illumination light on the sample has a first change amount parallel to the converging surface, and adjusting the second reflector so that the conjugate point of the spot of the first detector in the object space has a second change amount parallel to the photosensitive surface of the first detector in the conjugate plane in the object space, and the first change amount is equal to the second change amount, includes: adjusting, by the adjustment module, the first reflector and the second reflector so that the rotation angles of the first reflector and the second reflector are the same.

[0018] In a third aspect, the present disclosure provides an optical system, including: the monitoring system as described in the first aspect; a processing system, including: a light source assembly, the light source assembly being adapted to provide first illumination light to the first optical component.

[0019] Optionally, the first illumination light is further configured to form a second signal light after passing through the sample surface; the processing system further includes: a detection module, configured to collect the second signal light and detect the sample surface based on the second signal light.

[0020] In a fourth aspect, the present disclosure provides a working method of an optical system, including: providing first illumination light to a first optical component through a light source component; using the monitoring method of the monitoring system described in the second aspect, such that the first illumination light reflected by the first reflector of the first optical component and obliquely incident on the sample surface forms a first signal light, which is collected at the same position of a first detector by the sample surface reflecting the first illumination light; after the monitoring method, detecting the sample through a processing system.

[0021] Optionally, the first illumination light is further configured to form a second signal light after passing through the sample surface; detecting the sample through the processing system using the first illumination light includes: collecting, by a detection module, the second signal light formed by the first illumination light passing through the sample surface, and detecting the sample surface based on the second signal light.

[0022] In the monitoring system and its monitoring method, and the optical system and its working method provided by the present disclosure, the first illumination light is reflected by the first reflector of the first optical component and obliquely incident on the sample surface, and the sample surface reflects the first illumination light to form a first signal light; the imaging component of the second optical component uses the first signal light to image the sample surface onto the first detector; the first detector obtains a detection image of the sample surface based on the first signal light and forms a light spot on the photosensitive surface of the first detector, and the second reflector makes the light spot formed by the first signal light reflected by the sample surface at a preset calibration position on the photosensitive surface of the first detector be at a preset position; the adjustment module is configured to synchronously adjust the rotation angles of the first reflector and the second reflector relative to the normal plane of the sample surface, such that the first illumination light reflected by the sample surface at different heights perpendicular to the surface and at the same points along the sample surface forms a first signal light, which is collected at the same position of the first detector.

[0023] In the monitoring system provided by the present disclosure, during the process of synchronously adjusting the incident optical path of the first illumination light incident on the sample surface and the reflection optical path where the first signal light is located by the adjustment module to adjust the light spot to be at a preset position on the first detector, the incident position of the first illumination light on the sample surface is also synchronously adjusted, thereby eliminating the phenomenon of inaccurate detection position caused by the offset of the incident position of the first illumination light along the sample surface direction due to the height change of the sample surface, and thus improving the detection accuracy of the sample surface.

[0024] Other features and advantages of the present disclosure will be set forth in the following description, and in part will be obvious from the description, or may be learned by practice of the present disclosure. The objectives and other advantages of the present disclosure may be realized and attained by the structure particularly pointed out in the specification, claims and drawings. Description of the Drawings

[0025] The present disclosure will be described in more detail hereinafter based on embodiments and with reference to the drawings:

[0026] Figure 1 Schematic structural diagram of a monitoring system provided for an embodiment of the present disclosure.

[0027] Figure 2 Schematic structural diagram of a monitoring system provided for another embodiment of the present disclosure.

[0028] Figure 3 Schematic structural diagram of a monitoring system provided for another embodiment of the present disclosure.

[0029] Figure 4 Schematic structural diagram of a monitoring system provided for another embodiment of the present disclosure.

[0030] Figure 5 Schematic structural diagram of a monitoring system provided for another embodiment of the present disclosure.

[0031] Figure 6 Flowchart of a monitoring method for a monitoring system provided for an embodiment of the present disclosure.

[0032] Figure 7 Schematic structural diagram of an optical system provided for an embodiment of the present disclosure.

[0033] Figure 8 Flowchart of an operating method for an optical system provided for an embodiment of the present disclosure. Detailed Embodiments

[0034] In order to enable those skilled in the art to better understand the technical solutions of the present disclosure, and to fully understand and implement how the present disclosure applies technical means to solve technical problems and achieve corresponding technical effects, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. The embodiments of the present disclosure and each feature in the embodiments can be combined with each other without conflict, and the formed technical solutions are all within the protection scope of the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present disclosure.

[0035] It should be noted that the terms "first", "second", etc. in the description, claims and the above-mentioned drawings of the present disclosure are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0036] It should be noted that the steps shown in the flowchart of the drawings can be executed in a computer system such as a set of computer-executable instructions. And although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that here.

[0037] Figure 1 It is a schematic structural diagram of a monitoring system provided by an embodiment of the present disclosure. As Figure 1 shown, a monitoring system includes: a first optical component 100, a second optical component 200, and an adjustment module (not shown in the figure).

[0038] The first optical component 100 includes a first mirror 110. The first mirror 110 is used to reflect the first illumination light 90 and make the first illumination light 90 obliquely incident on the surface of the sample 300. The first illumination light 90 is reflected by the surface of the sample 300 to form a first signal light 91.

[0039] The second optical component 200 includes a second mirror 220, an imaging component 230, and a first detector 240. The imaging component 230 is used to image the surface of the sample 300 onto the first detector 240 by using the first signal light 91. The first detector 240 is used to obtain a detection image of the surface of the sample 300 according to the first signal light 91 and form a light spot 400 on the photosensitive surface of the first detector 240. The second mirror 220 is used to make the light spot 400 formed by the first signal light 91 reflected by the surface of the sample 300 at a preset calibration position be at a preset position on the photosensitive surface of the first detector 240.

[0040] The adjustment module is used to synchronously adjust the rotation angles of the first mirror 110 and the second mirror 220 relative to the normal plane of the surface of the sample 300, so that the first signal light 91 formed by the first illumination light 90 reflected by the points on the surface of the sample 300 with different heights perpendicular to its surface and the same along the surface of the sample 300 is collected at the same position of the first detector 240.

[0041] Reference Figure 1 As shown, the monitoring system can be applied to an optical system on the surface of a processed sample 300. The first optical component 100 is used to provide first illumination light 90 as detection light to the surface of the sample 300. The first illumination light 90 is reflected by the surface of the sample 300 to form first signal light 91. The second optical component 200 is used to image the first signal light 91 on the surface of the sample 300, and determine whether the light spot 400 formed by the first signal light 91 on the first detector 240 is at a preset position 500. According to the offset between the light spot 400 and the preset position 500, the first emitting mirror 110 and the second reflecting mirror 220 are adjusted by an adjustment module to automatically adjust the incident position 310 of the first illumination light 90 incident on the surface of the sample 300, so that when the height of the surface of the sample 300 changes, the adjustment module can make the first illumination light 90 at the same incident position on the surface of the sample 300, thereby improving the detection accuracy of the sample.

[0042] Specifically, referring to Figure 1 As shown, the first optical component 100 and the second optical component 200 are located on the same side of the sample 300. As Figure 1 shown, the first optical component 100 includes a first reflecting mirror 110 to obliquely incident the first illumination light 90 on the surface of the sample 300 through the first reflecting mirror. Obliquely incident on the surface of the sample 300 can be understood as the incident angle of the first illumination light 90 on the surface of the sample 300 being an acute angle.

[0043] Continuing to refer to Figure 1 , the first reflecting mirror 110 reflects the first illumination light 90 and obliquely incident it on the surface of the sample 300. The first illumination light 90 is reflected by the surface of the sample 300 to form first signal light 91, and the first signal light 91 is received by the second optical component 200.

[0044] Reference Figure 1 , the second optical component 200 includes a second reflecting mirror 220, an imaging component 230, and a first detector 240. The imaging component 230 can receive the first signal light 91 and use the first signal light 91 to image the surface of the sample 300 onto the first detector 240. The first detector 240 can obtain a detection image of the surface of the sample 300 according to the first signal light 91 and form a light spot 400 on the photosensitive surface of the first detector 240. The second reflecting mirror 220 is used to make the light spot 400 formed by the first signal light 91 reflected from the surface of the sample 300 at a preset calibration position on the photosensitive surface of the first detector 240 be at the preset position 500.

[0045] Among them, the preset calibration position is the height position of the sample 300 when detecting the surface of the sample 300. For example, the preset calibration position can be the position of the surface of the sample 300 at any height.

[0046] In this embodiment, the sample 300 used is, for example, a wafer. In other embodiments, the sample 300 can also be a chip, a display panel, a mobile phone glass shell, etc., which are samples capable of surface defect detection.

[0047] The preset position 500 is any position on the photosensitive surface of the first detector 240. Specifically, the preset position 500 can be the center of the photosensitive surface of the first detector 240.

[0048] Specifically, during the alignment process, the first signal light 91 reflected by the sample 300 in the preset calibration position can be made to form a light spot on the surface of the first detector 240 at the center of the photosensitive surface through the second mirror 220.

[0049] When detecting multiple samples, due to the different thicknesses of the samples 300 or the vibration of the samples 300, the height of the surface of the samples 300 will change in the thickness direction. Specifically, referring to Figure 1 and Figure 2 As shown, when detecting different samples 300, the position of the surface of the sample 300 may change in the second direction Z. For example, when the sample 300 needs to be replaced during the detection of the sample 300, the thickness of the replaced sample 300 is different from that of the previous sample 300. Therefore, the surface positions of different samples 300 shift in the second direction Z. As Figure 1 and Figure 2 shown, for example, when the thickness D2 of the replaced sample 300 is greater than the thickness D1 of the previous sample 300, without the adjustment module of the present application, the incident position 310 of the first illumination light 90 on the surface of the sample 300 will shift to the left in the first direction X, resulting in the light spot 400 formed by the first signal light 91 reflected by the surface of the sample 300 on the first detector 240 also shifting from the preset position 500. This light spot 400 is also the actual position of the imaging formed by the first signal light 91 on the photosensitive surface of the first detector 240. Therefore, by adjusting the incident position 310 of the first illumination light 90 on the surface of the sample 300, the same measurement point on the surfaces of samples 300 at different height positions can form light spots at the same position on the photosensitive surface of the first detector 240, thereby avoiding the change in the incident position of the first illumination light 90 on the surface of the sample 300 in the direction perpendicular to the height direction of the sample 300 due to the change in the surface height of the sample 300. The height direction is perpendicular to the surface of the sample 300.

[0050] Therefore, in the embodiments of the present application, an adjustment module is provided in the monitoring system. The adjustment device is used to synchronously adjust the rotation angles of the first mirror 110 and the second mirror 220 relative to the normal plane of the surface of the sample 300, so that the first illumination light 90 reflected from the same point on the surface of the sample 300 with different heights perpendicular to the surface of the sample 300 forms a first signal light 91, which is collected at the same position of the first detector.

[0051] In the monitoring system, when the height of the surface of the sample 300 changes, resulting in the offset of the incident position 310 of the first illumination light 90 on the surface of the sample 300, during the process of using the adjustment module to adjust the second mirror 220 to adjust the light spot 400 to the preset position 500 on the first detector 240, the first mirror 110 is also synchronously adjusted to adjust the incident position 310 of the first illumination light 90 on the surface of the sample 300, thereby eliminating the phenomenon of inaccurate detection position caused by the offset of the incident position 310 of the first illumination light 90 on the surface of the sample 300 due to the change in the height of the surface of the sample 300.

[0052] It should be noted that the adjustment module synchronously adjusts the first mirror 110 and the second mirror 220, not emphasizing the synchronization in time, but referring to the adjustment of both the first mirror 110 and the second mirror 220.

[0053] The preset calibration position is a position with a preset coordinate in the height direction. For example, the preset calibration position can be the position with a coordinate of 0 in the height direction of the coordinate system of the optical processing device.

[0054] The monitoring system synchronously adjusts the rotation angles of the first mirror 110 and the second mirror 220 relative to the normal plane of the surface of the sample 300 through the adjustment module, so as to synchronously adjust the incident optical path A of the first optical component 100 and the optical path (reflection optical path B) where the first signal light 91 is located, so that the first illumination light 90 reflected from the same point on the surface of the sample 300 with different heights perpendicular to the surface of the sample 300 forms a first signal light 91, which can be collected at the same position of the first detector 240, so as to eliminate the offset of the incident position 310 caused by the change in the height of the surface of the sample 300 of the first illumination light 90, and to accurately collect the position to be detected on the surface of the sample 300, thereby obtaining accurate position information of the defects on the surface of the sample 300 and improving the detection accuracy of the surface of the sample 300.

[0055] The first detector 240 is, for example, a Time Delay Integration (TDI) detector, or a Charge Coupled Device (CCD), or a Position Sensitive Detector (PSD), or a Photomultiplier Tube Array (PMT), which is not specifically limited herein.

[0056] In this embodiment, the monitoring system further includes a control system. The control system is configured to determine whether the light spot deviates from a preset position according to the detection image of the first detector. If so, the control system controls the adjustment module to synchronously adjust the rotation angles of the first mirror 110 and the second mirror 220 relative to the normal plane of the surface of the sample 300 until the light spot in the detection image is located at the preset position.

[0057] Specifically, the second optical component 200 forms a light spot 400 on the photosensitive surface of the first detector 240 by using the first signal light 91. The control system can obtain the detection image of the first detector 240, and the detection image includes a preset position 500 of the light spot imaging. It can be understood that the preset position 500 is a preset acquisition area within a certain range, and the size of the preset acquisition area can be set according to the actual situation. For example, the preset position can be the center of the detection image; it is not specifically limited herein. If the light spot 400 deviates from the preset position 500, that is, the light spot 400 is not formed within the range of the preset position 500, then the control system controls the adjustment module to synchronously adjust the rotation angles of the first mirror 110 and the second mirror 220 relative to the normal plane of the surface of the sample 300, so that the first illumination light 90 reflected by the same points on the surface of the sample 300 with different heights perpendicular to the surface forms the first signal light 91 to be collected at the same position of the first detector 240. If it is determined that the light spot 400 does not deviate from the preset position 500, that is, the light spot 400 is formed within the range of the preset position 500, then no adjustment is required.

[0058] Such as Figure 1 、 Figures 3 to 5 , the first optical component 100 further includes a first focusing mirror 120. The first focusing mirror 120 is configured to focus the first illumination light 90 onto the surface of the sample 300. Among them, the arrangement order of the first mirror 110 and the first focusing mirror 120 in the incident optical path A in the incident direction can be interchanged. Such as Figure 1 shown, the first mirror 110 and the first focusing mirror 120 are arranged along the incident optical path A of the first illumination light 90 in the incident direction. Such as Figure 4As shown, the first focusing mirror 120 and the first reflecting mirror 110 are arranged along the incident optical path A of the incident direction of the first illumination light 90. In the second optical component 200, the first detector 240 is always located in the optical path after the imaging component 230, and the positional relationship between the second reflecting mirror 220 and the imaging component 230 can be interchanged, as Figure 3 and Figure 4 shown, the second reflecting mirror 220 is located in the optical path between the imaging component 230 and the first detector 240. As Figure 5 shown, the second reflecting mirror 220 is located in the optical path before the imaging component 230, that is, the second reflecting mirror 220 is located in the optical path between the imaging component 230 and the sample 300.

[0059] Among them, the imaging component can be an integral structure or a structure composed of multiple components. As Figures 1 to 5 shown, for example, the imaging component 230 can include a first collimating mirror 231 and a second focusing mirror 232. The first collimating mirror 231 is used to collimate the first signal light 91, and the second focusing mirror 232 is used to focus the first signal light 91. As Figure 1 shown, the second reflecting mirror 220 can also be located in the optical path between the first collimating mirror 231 and the second focusing mirror 232.

[0060] As Figure 1 shown, the first optical component 100 is composed of a first reflecting mirror 110 and a first focusing mirror 120 arranged in sequence along the incident optical path A of the first illumination light 90. The first focusing mirror 120 is used to focus the first illumination light 90 reflected by the first reflecting mirror 110 onto the surface of the sample 300. The second optical component 200 is composed of a first collimating mirror 231, a second reflecting mirror 220, a second focusing mirror 232, and a first detector 240 located at the rear focal plane of the second focusing mirror 232, which are arranged in sequence along the reflection optical path B of the first signal light 91. The first collimating mirror 231 and the second focusing mirror 232 jointly use the first signal light 91 to image the surface of the sample 300. The second reflecting mirror 220 can be located at any position in the parallel optical path after the collimating plane of the first collimating mirror 231, and the first reflecting mirror 110 can be located at any position in the optical path before the first focusing mirror 120.

[0061] In a specific embodiment, as Figure 1 shown, the imaging component 230 includes a first collimating mirror 231 and a second focusing mirror 232. The first detector 240 is located at the rear focal plane of the second focusing mirror 232; the first reflecting mirror 110 and the first focusing mirror 120 are arranged along the incident direction of the first illumination light 90; the second reflecting mirror 220 is located between the first collimating mirror 231 and the second focusing mirror 232; the first illumination light reflected by the first reflecting mirror 110 is parallel light. The focal length of the first focusing mirror 120 is equal to the focal length of the first collimating mirror 231.

[0062] Reference Figure 1 As shown, the optical paths on both sides of the normal plane of the surface of sample 300 include an incident optical path A and a reflected optical path B. Figure 1 The reflected optical path B from the second reflector 220 to the surface of sample 300 and the incident optical path A from the first reflector 110 to sample 300 shown are symmetric about the normal plane of the surface of sample 300. In other embodiments of the present application, the reflected optical path B from the second reflector 220 to the surface of sample 300 and the incident optical path A from the first reflector 110 to sample 300 may not be symmetric about the normal plane of the surface of sample 300.

[0063] In one embodiment, specifically, during the process that the control system controls the adjustment module to synchronously adjust the rotation angles of the first reflector 110 and the second reflector 220 relative to the normal plane of the surface of sample 300, the control system can be used to control the adjustment module to make the incident position 310 of the first illumination light 90 on sample 300 have a first change amount along a plane parallel to the converging surface of the first focusing mirror 120, and the conjugate point of the light spot of the first detector 240 in the object space has a second change amount along a direction parallel to the photosensitive surface of the first detector 240 in the conjugate plane in the object space, and the first change amount is equal to the second change amount.

[0064] Reference Figure 1 and Figure 2 , when the surface of sample 300 changes in the second direction Z, the adjustment module can be used to synchronously adjust the first reflector 110 and the second reflector 220 to rotate in opposite directions relative to the normal plane of the surface of sample 300, so that the incident position 310 of the first illumination light 90 on sample 300 has a first change amount along a plane parallel to the converging surface, and the conjugate point of the light spot of the first detector 240 in the object space has a second change amount along a direction parallel to the photosensitive surface of the first detector 240 in the conjugate plane in the object space, and the first change amount is equal to the second change amount, so as to adjust the symmetric optical path, so as to eliminate the offset of the incident position 310 caused by the height change of the surface of sample 300 of the first illumination light 90, and accurately collect the position to be detected on the surface of sample 300, thereby obtaining accurate surface information of sample 300 and improving the processing precision of the surface of sample 300.

[0065] Specifically, as Figure 1 shown, both the first focusing mirror 120 and the first collimating mirror 231 have focal lengths. The focal length of the first focusing mirror 120 is denoted as f 1 , and the focal length of the first collimating mirror 231 is denoted as f 2 , and the adjustment module can be used to make the first change amount of the incident position 310 of the first illumination light 90 on sample 300 along a plane parallel to the converging surface be f 1 *tan∠1 or f 1 *∠1; ∠1 is the rotation angle of the first reflector, and f 1is the focal length of the first focusing lens 120. Meanwhile, the second change amount of the spot of the first detector 240 on the conjugate point in the object space along the direction parallel to the photosensitive surface of the first detector 240 in the conjugate plane of the object space is adjusted by the adjustment module to be f 2 *tan∠2 or f 2 *∠2, f 2 is the focal length of the first collimating lens 231. Among them, the first change amount is equal to the second change amount, that is, the control system controls the adjustment module to make f 1 *tan∠1 = f 2 *tan∠2 or f 1 *∠1 = f 2 *∠2. When the first reflecting mirror rotates by ∠1, correspondingly, the second reflecting mirror rotates by ∠2. Among them, when the focal length f 1 of the first focusing lens 120 is equal to the focal length f 2 of the first collimating lens 231, then the rotation angle ∠1 of the first reflecting mirror 110 is equal to the rotation angle ∠2 of the second reflecting mirror 220, and the adjustment directions of the first reflecting mirror 110 and the second reflecting mirror 220 are opposite, and the adjustment amounts are the same. That is, when adjusting the incident optical path A and the reflected optical path B by using the adjustment module, the first reflecting mirror 110 and the second reflecting mirror 220 can be synchronously adjusted to rotate in opposite directions along the normal plane of the surface of the sample 300, so that the rotation angle of the first reflecting mirror 110 is the same as the rotation angle of the second reflecting mirror 220. The first illumination light is incident on the first focusing lens 120 in parallel.

[0066] Among them, both the first change amount and the second change amount are vectors. For example, the projection of the first change amount on the normal line of the surface of the sample 300 along the second direction Z upward can be recorded as the positive direction, and the projection of the first change amount on the normal line of the surface of the sample 300 along the opposite direction of the second direction Z downward is recorded as the negative direction. When the first change amount is equal to the second change amount, the projection direction of the second change amount is also the same as the projection direction of the first change amount.

[0067] In one embodiment, as shown in Figure 3 , the first optical assembly 100 is composed of a first reflecting mirror 110 and a first focusing lens 120 arranged in sequence along the incident optical path A of the first illumination light 90, and the second reflecting mirror 220 is located in the optical path between the imaging assembly 230 and the first detector 240. The second optical assembly 200 is composed of an imaging assembly 230, a second reflecting mirror 220 and a first detector 240 arranged in sequence along the reflected optical path B of the first signal light 91. In this embodiment, the imaging assembly 230 includes a first collimating lens 231 and a second focusing lens 232 arranged along the reflected optical path B. The first detector 240 is located at the rear focal plane of the second focusing lens 232.

[0068] It should be noted that in the above embodiments, the first detector 240 is located at the rear focal plane of the second focusing mirror 232, and the optical path between the first collimating mirror 231 and the second focusing mirror 232 is a parallel optical path. In other embodiments, the first detector 240 may not be located at the rear focal plane of the second focusing mirror 232, and the optical path between the first collimating mirror 231 and the second focusing mirror 232 is not parallel. The first reflecting mirror 110 may be located between the first collimating mirror 231 and the second focusing mirror 232. The adjustment angles of the synchronous adjustment of the first reflecting mirror 110 and the second reflecting mirror 220 only need to ensure that the first change amount is equal to the second change amount, and will not be elaborated here.

[0069] In this embodiment, the first reflecting mirror is located in the parallel optical path, and the second emitting mirror is also located in the parallel optical path. The first reflection is at any position between the first collimating mirror and the second focusing mirror, and the second reflecting mirror is at any position in the parallel optical path after the first focusing mirror. The rotation angles and rotation directions of the first reflecting mirror and the second reflecting mirror are fixed and unchanged. Therefore, the position requirements during the installation of the first reflecting mirror and the second reflecting mirror are very low, which is more conducive to accurate monitoring.

[0070] Reference Figure 3 In this embodiment of, when the surface of the sample 300 changes in the second direction Z, the rotation directions of the first reflecting mirror 110 and the second reflecting mirror 220 can be adjusted through the adjustment module, so that they rotate in opposite directions, and the first reflecting mirror 110 is adjusted through the adjustment module so that the incident position 310 of the first illumination light 90 on the sample 300 has a first change amount of f 1 *tan∠1 or f 1 *∠1; ∠1 is the rotation angle of the first reflecting mirror 110, f 1 is the focal length of the first focusing mirror 120; the second reflecting mirror 220 is adjusted through the adjustment module so that the light spot of the first detector 240 at the conjugate point in the object space has a second change amount of (d 3* ∠2) / M or (d 3* tan∠2) / M in the direction parallel to the photosensitive surface of the first detector 240 in the conjugate plane in the object space. d 3 is the distance between the second reflecting mirror 220 and the first detector 240, ∠2 is the rotation angle of the second reflecting mirror 220, and M is the magnification of the imaging assembly 230; among them, the magnification of the imaging assembly 230 can be the sum value of the magnification of the first collimating mirror 231 and the magnification of the second focusing mirror 232. Among them, when the first reflecting mirror 110 and the second reflecting mirror 220 are adjusted through the adjustment module, the first change amount is made equal to the second change amount, that is, the control system controls the adjustment module to make f 1 *tan∠1 = (d 3* tan∠2) / M, or f1 *∠1 = (d 3* ∠2) / M, so that the first signal light 91 formed by the first illumination light 90 reflected from points at different heights perpendicular to the surface of the sample 300 is collected at the same position by the first detector 240. When the first mirror rotates by ∠1, correspondingly, the second mirror rotates by ∠2. The first illumination light is incident parallel to the first focusing mirror.

[0071] In one embodiment, illustratively, the arrangement of the first focusing mirror 120 and the first mirror 110 in the incident optical path A can also be changed. As Figure 4 shown, the first optical assembly 100 is composed of a first focusing mirror 120 and a first mirror 110 arranged in sequence along the incident optical path A of the first illumination light 90, and the second optical assembly 200 is composed of an imaging assembly 230, a second mirror 220, and a first detector 240 arranged in sequence along the reflection optical path B of the first signal light 91. In this embodiment, the imaging assembly 230 includes a first collimating mirror 231 and a second focusing mirror 232 arranged along the reflection optical path B. The first detector 240 is located at the rear focal plane of the second focusing mirror 232.

[0072] Reference Figure 4 , in this monitoring system, when the surface of the sample 300 changes in the second direction Z, the rotation directions of the first mirror 110 and the second mirror 220 can be adjusted by the adjustment module so that they rotate in opposite directions. The adjustment module adjusts the first mirror 110 so that the incident position 310 of the first illumination light 90 on the sample 300 has a first change amount along a direction parallel to the converging surface, and the first change amount is d 1 *tan∠1, or the first change amount is d 1 *∠1, d 1 is the distance between the first mirror 110 and the converging surface of the first illumination light; the adjustment module adjusts the second mirror 220 so that the spot of the first detector 240 has a second change amount in the direction of the conjugate point in the object space along a direction parallel to the photosensitive surface of the first detector 240 in the conjugate plane of the object space, which is (d 3* ∠2) / M or (d 3* tan∠2) / M, d 3 is the distance between the second mirror 220 and the first detector 240, ∠2 is the rotation angle of the second mirror 220, and M is the magnification of the imaging assembly 230; among them, the magnification of the imaging assembly 230 can be the sum of the magnification of the first collimating mirror 231 and the magnification of the second focusing mirror 232. Among them, when the adjustment module adjusts the first mirror 110 and the second mirror 220, the first change amount is made equal to the second change amount, that is, the control system controls the adjustment module so that d 1 *tan∠1 = (d 3* tan∠2) / M, or d1 *∠1 = (d 3* ∠2) / M, so that the first signal light 91 formed by the first illumination light 90 reflected from points at different heights perpendicular to the surface of the sample 300 is collected at the same position by the first detector 240. When the first mirror rotates by ∠1, correspondingly, the second mirror rotates by ∠2.

[0073] In one embodiment, illustratively, the arrangement of the second mirror 220 and the imaging assembly 230 in the reflection optical path B can also be changed. As Figure 5 shown, the first optical assembly 100 is composed of a first focusing mirror 120 and a first mirror 110 arranged in sequence along the incident optical path A of the first illumination light 90, and the second optical assembly 200 is composed of a second mirror 220, an imaging assembly 230, and a first detector 240 arranged in sequence along the reflection optical path B of the first signal light 91. In this embodiment, the imaging assembly 230 includes a first collimating mirror 231 and a second focusing mirror 232 arranged along the reflection optical path B. The first detector 240 is located at the rear focal plane or other positions of the second focusing mirror 232.

[0074] As Figure 5 shown, when the surface of the sample 300 changes in the second direction Z in this monitoring system, the first mirror 110 is adjusted by the adjustment module so that the incident position 310 of the first illumination light 90 on the sample 300 has a first change amount of d 1 *tan∠1, or d 1 *∠1, d 1 is the distance between the first mirror 110 and the converging surface of the first illumination light; the second mirror 220 is adjusted by the adjustment module so that the spot of the first detector 240 has a second change amount of d 2 *∠2 or d 2* tan∠2 in the direction of the conjugate plane of the object with respect to the photosensitive surface of the first detector 240 parallel to the conjugate point of the object; d 2 is the distance between the second mirror and the object focal plane of the imaging assembly; wherein, when the first mirror 110 and the second mirror 220 are adjusted by the adjustment module, the first change amount is made equal to the second change amount, that is, the control system controls the adjustment module so that d 1 *tan∠1 = d 2* tan∠2, or d 1 *∠1 = d 2* tan∠2, so that the first signal light 91 formed by the first illumination light 90 reflected from points at different heights perpendicular to the surface of the sample 300 is collected at the same position by the first detector 240. When the first mirror rotates by ∠1, correspondingly, the second mirror rotates by ∠2.

[0075] Therefore, the monitoring system can adjust the first mirror 110 through the adjustment module to correct the incident position 310 of the first illumination light 90 on the surface of the sample 300, and adjust the second mirror 220 to correct the light spot 400 formed by the first signal light 91 on the first detector 240 to the same preset position 500 of the first detector 240, thereby improving the detection accuracy of the surface of the sample 300.

[0076] In the above embodiment, in order to ensure that the adjustment angles of the first mirror 110 and the second mirror 220 are the same during the adjustment process, the optical path from the first mirror 110 to the surface of the sample 300 is symmetric with respect to the normal plane of the surface of the sample 300 to the optical path of the second mirror 220 to the surface of the sample 300. In other embodiments, they may not be symmetric.

[0077] In this embodiment, the adjustment module is a piezoelectric adjustment device, or a motor or a manual control module.

[0078] Figure 6 It is a flowchart of a monitoring method of a monitoring system provided by an embodiment of the present disclosure. The monitoring method of the monitoring system is used for the monitoring system provided by the above embodiment, as Figure 6 shown, a monitoring method of a monitoring system includes:

[0079] Step S110: Reflect the first illumination light through the first mirror and obliquely incident the first illumination light on the surface of the sample 300, and the surface of the sample reflects the first illumination light to form a first signal light;

[0080] Step S120: Obtain a detection image of the surface of the sample through a second optical component;

[0081] Step S130: Perform monitoring processing on the sample according to the detection image. The monitoring processing includes: if the light spot deviates from the preset position, synchronously adjust the rotation angles of the first mirror and the second mirror relative to the normal plane of the surface of the sample through the adjustment module, so that the first illumination light reflected by the same points on the surface of the sample with different heights perpendicular to the surface and along the surface of the sample forms a first signal light to be collected at the same position of the first detector.

[0082] Combined with Figure 1 and Figure 2As shown, during or before the processing of the sample 300, when the thickness D2 of the replaced sample 300 is greater than the thickness D1 of the previous sample 300 or the sample vibrates up and down during the processing, the incident position 310 of the first illumination light 90 on the surface of the sample 300 shifts in the first direction X. Synchronously, the spot 400 formed by the first signal light 91 reflected from the surface of the sample 300 on the first detector 240 and the preset position 500 also shift. In order to obtain the shift situation of the spot 400 and the preset position 500 to obtain the shift situation of the incident position 310 on the surface of the sample 300, it is necessary to obtain the detection image of the surface of the sample 300 through the second optical component 200; according to the shift situation of the spot 400 and the preset position 500 in the detection image, the adjustment module is used to synchronously adjust the first mirror 110 and the second mirror 220 to rotate in opposite directions along the normal plane of the surface of the sample 300, so that the first illumination light 90 reflected by the same points on the surface of the sample 300 with different heights perpendicular to the surface forms the first signal light to be collected at the same position of the first detector.

[0083] The monitoring method of this monitoring system can, when the surface of the sample 300 changes in the second direction Z perpendicular to the surface of the sample 300, automatically calibrate the incident position 310 of the first illumination light 90 on the surface of the sample 300 by adjusting the incident optical path A and the reflection optical path B of the first optical component 100, so as to obtain accurate defect information on the surface of the sample 300 and improve the detection accuracy of the sample 300.

[0084] In one embodiment, in step S130, monitoring and processing the sample according to the detection image includes:

[0085] Step S132, judging whether the spot deviates from the preset position according to the detection image; if the spot deviates from the preset position, execute step S134; if the spot does not deviate from the preset position, no adjustment is required;

[0086] Step S134, determining the rotation directions of the first mirror and the second mirror according to the deviation direction of the spot from the preset position, and synchronously adjusting the rotation angles of the first mirror and the second mirror relative to the normal plane of the sample surface according to the rotation directions until the spot is at the preset position.

[0087] Figures 1 to 5 The monitoring systems of the illustrated embodiments can all be cited here.

[0088] Specifically, refer to Figure 1 and Figure 2, the detection image of the first detector 240 can be obtained, and the preset position 500 of the spot imaging is included in the detection image. If the spot 400 is not formed within the range of the preset position 500, that is, the position of the spot 400 is offset from the preset position 500, it means that the incident position 310 of the first illumination light 90 on the sample is also offset. The offset situation between the spot 400 and the preset position 500 includes the offset direction and the offset amount.

[0089] As Figure 2 shown, if the spot position 400 has an offset amount in the first direction relative to the preset position 500, it can be obtained that the incident position 310 of the sample has an offset amount in the first direction relative to the point to be measured of the sample. Therefore, according to the deviation direction of the spot from the preset position, the rotation directions of the first mirror and the second mirror are determined, and according to the rotation direction, the rotation angles of the first mirror 110 and the second mirror 220 relative to the normal plane of the surface of the sample 300 are synchronously adjusted, and the position of the spot 400 is gradually adjusted until the spot is within the range of the preset position 500. Through such a repeated adjustment process, the first illumination light 90 perpendicular to the surface of the sample 300 and reflected by the same points along the surface of the sample forms the first signal light 91 and is collected at the same position by the first detector 240, so that the incident position 310 of the first illumination light 90 on the surface of the sample 300 does not shift, so as to collect the imaging of the surface of the sample 300 at the same position, thereby improving the detection accuracy of the surface of the sample 300.

[0090] In other embodiments of the present application, if the spot deviates from the preset position, step S134 is executed, including: determining the rotation angles and rotation directions of the first mirror and the second mirror according to the offset amount and the deviation direction of the spot from the preset position; after determining the rotation angles and rotation directions, the first mirror and the second mirror are respectively adjusted by the adjustment module. Specifically, before the monitoring process, the first corresponding relationship between the offset amount of the spot deviating from the preset position and the rotation angle, and the second corresponding relationship between the deviation direction and the rotation direction can be stored in the monitoring system, and the rotation angles and rotation directions are directly obtained according to the first corresponding relationship and the second corresponding relationship during the monitoring process. The first corresponding relationship can be a data list or a functional relationship. This method can avoid repeatedly adjusting the first mirror and the second mirror, thereby improving the processing speed.

[0091] If it is determined according to the detection image that the spot 400 does not deviate from the preset position 500 after replacing the sample or during the process of the processing system processing the sample, that is, the spot 400 is formed within the range of the preset position 500, it means that the incident position 310 of the first illumination light 90 on the sample does not shift relative to the point to be measured of the sample, and no adjustment is required.

[0092] The monitoring method of the monitoring system monitors the offset of the light spot 400 from the preset position 500 according to the detected image, so as to synchronously adjust the incident optical path A of the first optical component 100 and the optical path (reflection optical path B) where the first signal light 91 is located according to the offset between the two, so that the first signal light 91 formed by the first illumination light 90 reflected by the sample 300 along the points with different surface heights perpendicular to the surface and the same along the sample surface can be collected at the same position of the first detector 240, so as to calibrate the offset phenomenon of the light spot caused by the position offset of the incident position 310 of the first illumination light 90 due to the change of the surface height of the sample 300, thereby realizing the automatic correction of the incident position 310 of the first illumination light 90 on the surface of the sample 300 and improving the detection accuracy of the surface of the sample 300.

[0093] In one embodiment, in step S130, as Figure 5 shown, there is no reflecting element between the first reflecting mirror 110 and the sample 300, and there is no reflecting element between the second reflecting mirror 220 and the surface of the sample 300; the rotation angles of the first reflecting mirror 110 and the second reflecting mirror 220 relative to the normal plane of the surface of the sample 300 are synchronously adjusted by the adjustment module, including: synchronously adjusting the first reflecting mirror 110 and the second reflecting mirror 220 to rotate in opposite directions relative to the normal plane of the surface of the sample 300 by the adjustment module.

[0094] Specifically, when there is no reflecting element between the first reflecting mirror 110 and the sample 300 and between the second reflecting mirror 220 and the sample 300, that is, there is no other reflecting element between the first reflecting mirror 110 and the sample 300 that changes the oblique incident direction of the first illumination light 90 and the sample 300 surface, and there is no other reflecting element between the second reflecting mirror 220 and the sample 300 that changes the optical path direction of the first signal light 91 reflected to the second reflecting mirror 220, when using this rotation method for adjustment, the first reflecting mirror 110 and the second reflecting mirror 220 can be synchronously adjusted by the adjustment module to rotate in opposite directions relative to the normal plane of the surface of the sample 300, so that the first signal light 91 formed by the first illumination light 90 reflected by the sample 300 along the points with different surface heights perpendicular to the surface and the same along the sample surface can be collected at the same position of the first detector 240, so as to calibrate the offset phenomenon of the light spot caused by the position offset of the incident position 310 of the first illumination light 90 due to the change of the surface height of the sample 300, thereby realizing the automatic correction of the incident position 310 of the first illumination light 90 on the surface of the sample 300 and the position of the light spot 400 formed by the first signal light 91 on the first detector 240.

[0095] In one embodiment, a reflecting element may be disposed between the first mirror 110 and the sample 300, and a reflecting element may also be disposed between the second mirror 220 and the sample 300. For example, when an even number of reflecting elements are disposed between the first mirror 110 and the sample 300, and an even number of reflecting elements are disposed between the second mirror 220 and the sample 300, the first mirror 110 and the second mirror 220 can be synchronously adjusted by the adjustment module to rotate in opposite directions along the normal plane of the surface of the sample 300. Alternatively, when an odd number of reflecting elements are disposed between the first mirror 110 and the sample 300, and an odd number of reflecting elements are disposed between the second mirror 220 and the sample 300, the first mirror 110 and the second mirror 220 can be synchronously adjusted by the adjustment module to rotate in opposite directions along the normal plane of the surface of the sample 300.

[0096] In another embodiment, when an even number of reflecting elements are disposed between the first mirror 110 and the sample 300, and a single reflecting element is disposed between the second mirror 220 and the sample 300, the first mirror 110 and the second mirror 220 can be synchronously adjusted by the adjustment module to rotate in the same direction along the normal plane of the surface of the sample 300. Alternatively, when an odd number of reflecting elements are disposed between the first mirror 110 and the sample 300, and an even number of reflecting elements are disposed between the second mirror 220 and the sample 300, the first mirror 110 and the second mirror 220 can be synchronously adjusted by the adjustment module to rotate in the same direction along the normal plane of the surface of the sample 300.

[0097] For example, when two reflecting elements are disposed between the first mirror 110 and the sample 300, and the oblique incident direction of the first illumination light 90 on the surface of the sample 300 remains unchanged after the optical path of the first illumination light 90 is adjusted by the two reflecting elements, and two reflecting elements are disposed between the second mirror 220 and the sample 300, and the optical path direction of the first signal light 91 reflected to the second mirror 220 remains unchanged after the optical path of the first signal light 91 is adjusted by the two reflecting elements, the first mirror 110 and the second mirror 220 can be synchronously adjusted by the adjustment module to rotate in opposite directions along the normal plane of the surface of the sample 300.

[0098] In one embodiment, in the monitoring method of the monitoring system, synchronously adjusting the first mirror 110 and the second mirror 220 to rotate in opposite directions along the normal plane of the surface of the sample 300 by the adjustment module includes:

[0099] The first mirror 110 is adjusted by an adjustment module so that the incident position 310 of the first illumination light 90 on the sample 300 has a first change amount parallel to the converging surface, and the second mirror 220 is adjusted so that the spot of the first detector 240 has a second change amount in the direction of the object conjugate plane parallel to the photosensitive surface of the first detector 240 in the object space, and the first change amount is equal to the second change amount.

[0100] Reference Figures 3 - 4 , the second mirror 220 is located in the optical path between the imaging assembly 230 and the first detector 240, and the monitoring method further includes: adjusting the first mirror 110 and the second mirror 220 to rotate in opposite directions by an adjustment module, and adjusting the second mirror 220 by the adjustment module so that the second change amount is (d 3* ∠2) / M or (d 3* tan∠2) / M, d 3 is the distance between the second mirror 220 and the first detector 240, ∠2 is the rotation angle of the second mirror 220, and M is the magnification of the imaging assembly 230.

[0101] Reference Figure 5 , the second mirror 220 is located in the optical path between the imaging assembly 230 and the sample 300; the monitoring method further includes: adjusting the first mirror 110 and the second mirror 220 to rotate in opposite directions by an adjustment module, and adjusting the second mirror 220 by the adjustment module so that the second change amount is d 2 *∠2 or d 2* tan∠2; d 2 is the distance between the second mirror 220 and the object focal plane of the imaging assembly.

[0102] Reference Figure 1 , the imaging assembly 230 includes a first collimator 231 and a second focusing mirror 232. The first collimator 231 is used to collimate the first signal light 91, and the second focusing mirror 232 is used to focus and image the first signal light 91; the second mirror 220 is located in the optical path between the first collimator 231 and the second focusing mirror 232; the monitoring method further includes: adjusting the first mirror 110 and the second mirror 220 to rotate in opposite directions by an adjustment module, and adjusting the second mirror 220 by the adjustment module so that the second change amount is f 2 *tan∠2 or f 2 *∠2, f 2 is the focal length of the first collimator 231.

[0103] Reference Figure 1 and Figure 3, the first optical component 100 further includes a first focusing mirror 120, and the focal length of the first focusing mirror 120 is equal to the focal length of the first collimating mirror 231; the first reflecting mirror 110 and the first focusing mirror 120 are arranged along the incident direction of the first illumination light 90; the monitoring method further includes: adjusting the first reflecting mirror 110 through an adjustment module to make the first change amount be f 1 *tan∠1 or f 1 *∠1; ∠1 is the rotation angle of the first reflecting mirror 110, and f 1 is the focal length of the first focusing mirror 120.

[0104] Reference Figure 4 and Figure 5 , the first focusing mirror 120 and the first reflecting mirror 110 are arranged along the incident direction of the first illumination light, and the working method further includes: adjusting the first reflecting mirror 110 through an adjustment module to make the first change amount be d 1 *tan∠1 or d 1 *∠1, d 1 is the distance between the first reflecting mirror 110 and the converging surface of the first illumination light.

[0105] In this embodiment, during the process of synchronously adjusting the first reflecting mirror 110 and the second reflecting mirror 220 to rotate in opposite directions along the normal plane of the surface of the sample 300 by using the adjustment module, the rotation angles of the first reflecting mirror 110 and the second reflecting mirror 220 are synchronously adjusted, so as to adjust the incident optical path A of the first optical component 100 and the reflection optical path B of the first optical component 100, so as to synchronously adjust the position of the spot 400 formed by the first signal light 91 on the first detector 240 and the incident position 310 of the first illumination light 90 on the surface of the sample 300, so as to obtain accurate surface defect information of the sample 300 and improve the detection accuracy of the sample 300.

[0106] If the optical path from the first mirror to the sample surface is symmetric with respect to the normal plane of the sample surface to the optical path from the second mirror to the sample surface; or, the imaging assembly includes a first collimator and a second focusing mirror, and the first detector is located at the rear focal plane of the second focusing mirror; the first mirror and the first focusing mirror are arranged along the incident direction of the first illumination light; the second mirror is located between the first collimator and the second focusing mirror; the first illumination light reflected by the first mirror is parallel light, and the focal length of the first focusing mirror is equal to the focal length of the first collimator; the adjustment module is used to adjust the first mirror so that the incident position of the first illumination light on the sample has a first change amount along a direction parallel to the converging surface, and the second mirror is adjusted so that the conjugate point of the first detector spot in the object space has a second change amount along a direction parallel to the photosensitive surface of the first detector in the conjugate plane of the object space, and the first change amount is equal to the second change amount, including: adjusting the first mirror and the second mirror by the adjustment module so that the rotation angles of the first mirror and the second mirror are the same.

[0107] Figure 7 FIG. is a schematic structural diagram of an optical system provided by an embodiment of the present disclosure. As Figure 7 shown, an optical system includes: the monitoring system and the processing system provided in any one of the above embodiments, wherein the processing system includes a light source assembly, and the light source assembly is adapted to provide first illumination light to the first optical component 100.

[0108] It should be noted that Figures 1 to 5 the monitoring systems of the illustrated embodiments can all be introduced into this embodiment.

[0109] Specifically, in this embodiment, in combination with Figure 1 and Figure 7 for detailed description, the light source assembly includes a light source 52 and a beam splitting assembly PBS. The beam splitting assembly PBS splits the light emitted by the light source 52 into first illumination light and second illumination light. The incident angles of the first illumination light and the second illumination light on the sample surface are different. The first illumination light is obliquely incident on the sample surface, and the second illumination light can be obliquely incident or vertically incident on the sample surface. As Figure 7 shown by the dashed part 70 in the figure is the second illumination light emitted by the beam splitting assembly PBS.

[0110] In one embodiment, the first illumination light and the second illumination light are also provided by different light sources. Exemplarily, the light source assembly may further include a plurality of light sources to generate first illumination light and second illumination light with different incident angles using different light sources.

[0111] As Figure 7As shown, the first illumination light 90 is emitted toward the first optical component 100, and can be reflected by the first reflector 110 of the first optical component 100 so as to be obliquely incident on the surface of the sample 300. The surface of the sample 300 reflects the first illumination light 90 to form a first signal light (not shown in the figure).

[0112] In the optical system, the second optical component 200 in the monitoring system is used to image the surface of the sample 300 with the first signal light 91, and detect whether the position of the light spot 400 formed by the first signal light 91 on the first detector 240 is at a preset position, so as to adjust the first transmitting mirror 110 and the second reflecting mirror 220 through the adjustment module according to the offset of the light spot 400 from the preset position to automatically adjust the incident position 310 of the first illumination light 90 incident on the surface of the sample 300 on the surface of the sample 300, so that when the height of the surface of the sample 300 changes, the first illumination light 90 can be incident on the same point to be measured through the adjustment module, thereby improving the detection accuracy of the sample.

[0113] The embodiment of the present application provides an optical system, which includes the monitoring system provided in the above embodiment. Since the principle of solving the problem in the optical system is similar to that of the above monitoring system, the implementation of the monitoring system in the optical system can refer to the implementation of the above monitoring system, and the repeated parts will not be repeated.

[0114] In this optical system, Figure 7 As shown, the first illumination light 90 is also used to form a second signal light 75 after passing through the surface of the sample 300; the processing system also includes: a detection module, the detection module is used to collect the second signal light 75, and detect the surface of the sample 300 according to the second signal light 75. Specifically, in this embodiment, the second signal light 75 is formed by the first illumination light 90 being scattered by the surface of the sample 300.

[0115] Continue to refer Figure 7 As shown, the optical system also includes: the detection module includes a collecting mirror 78 and a second image detector 80. The optical path of the first illumination light 90 after being reflected by the surface of the sample 300 is received by the second optical component, and the first illumination light 90 is also scattered by the surface of the sample 300 to form a second signal light 75. The detection module collects the second signal light 75 scattered from the surface of the sample 300 through the collecting mirror 78; the second signal light 75 from the collecting mirror 78 is obtained through the second image detector 80, and the surface of the sample 300 is detected according to the second signal light 75. Exemplarily, the collecting mirror 78 can be a lens, or a reflective cup, the reflective cup is an ellipsoidal mirror or a parabolic mirror, and the second image detector 80 is, for example, a photodetector (photomultiplier tube, PMT).

[0116] The processing system further includes a carrying device for carrying a sample; a driver for driving the relative movement of the sample and the processing system to enable the processing system to perform a scanning process on the surface of the sample; when detecting the surface of the sample 300 according to the second signal light 75, the second image detector 80 is specifically configured to determine the position of the target to be measured along the direction parallel to the surface of the sample according to the movement).

[0117] In other embodiments, the processing system may not include a detection component, and the processing system is specifically configured to perform photolithography or cutting on the sample 300 according to the first illumination light 90. The processing system may be a laser cutting system or a photolithography system.

[0118] Figure 8 A working method of an optical system provided by an embodiment of the present disclosure is applied to the optical system provided by the above embodiment, as Figure 8 shown, a working method of an optical system includes:

[0119] Step S210, providing first illumination light to the first optical component through the light source component;

[0120] Step S220, using the monitoring method of the above monitoring system, enabling the first illumination light reflected by the points on the sample with different surface heights perpendicular to the surface and the same along the surface of the sample to form a first signal light and be collected at the same position of the first detector;

[0121] Step S230, after the monitoring method, the processing system uses the first illumination light to detect the sample.

[0122] Embodiment examples of the monitoring method of the monitoring system of the present application can all be introduced into this embodiment. Specifically, taking Figure 1 and Figure 7 shown as examples for detailed description.

[0123] Refer to Figure 1 and Figure 7As shown, the first illumination light 90 is provided to the first optical component 100 by the light source component. The first illumination light 90 can be reflected by the first mirror 110 of the first optical component 100 and obliquely incident on the surface of the sample 300. The first illumination light 90 reflected by the surface of the sample 300 forms a first signal light (not shown in the figure); the first illumination light 90 scattered by the surface of the sample 300 forms a second signal light 75. The second optical component 200 is used to obtain a detection image of the surface of the sample 300 according to the first signal light 91, and determine whether the position of the light spot 400 formed by the first signal light 91 on the first detector 240 is at a preset position 500. According to the offset between the light spot 400 and the preset position 500, the rotation directions and angles of the first mirror 110 and the second mirror 220 are adjusted to automatically adjust the incident position 310 of the first illumination light 90 incident on the surface of the sample 300, so that when the height of the surface of the sample 300 changes, the first illumination light 90 can be incident at the same point to be measured, thereby improving the detection accuracy of the sample. After being adjusted by the monitoring method of the monitoring system, the second signal light 75 scattered from the surface of the sample 300 is collected by the detection module in the processing system; the second signal light 75 from the collection mirror 78 is obtained by the second image detector 80, and the surface of the sample 300 is detected according to the second signal light 75 light.

[0124] In the monitoring method of the above monitoring system, the rotation angles of the first mirror and the second mirror relative to the normal plane of the sample surface are synchronously adjusted by the adjustment module according to the detection image, including: judging whether the light spot deviates from the preset position according to the detection image; if the light spot deviates from the preset position, determining the rotation directions of the first mirror and the second mirror according to the deviation direction of the light spot from the preset position, and synchronously adjusting the rotation angles of the first mirror and the second mirror relative to the normal plane of the sample surface until the light spot is at the preset position.

[0125] In the monitoring method of the above monitoring system, there is no reflection element between the first mirror and the sample, and there is no reflection element between the second mirror and the sample surface; or, there are an even number of reflection elements between the first mirror and the sample, and there are an even number of reflection elements between the second mirror and the sample surface; the rotation angles of the first mirror and the second mirror relative to the normal plane of the sample surface are synchronously adjusted by the adjustment module, including: synchronously adjusting the first mirror and the second mirror to rotate in opposite directions relative to the normal plane of the sample surface by the adjustment module.

[0126] In the monitoring method of the above monitoring system, the rotation angles of the first mirror 110 and the second mirror 220 relative to the normal plane of the surface of the sample 300 are synchronously adjusted by the adjustment module, including: adjusting the first mirror 110 by the adjustment module to make the incident position 310 of the first illumination light 90 on the sample 300 have a first change amount parallel to the converging surface, and adjusting the second mirror 220 to make the spot of the first detector 240 have a second change amount parallel to the photosensitive surface of the first detector 240 in the conjugate plane of the object space at the conjugate point in the object space, and the first change amount is equal to the second change amount.

[0127] In the monitoring method of the above monitoring system, if the optical path from the first mirror to the surface of the sample is symmetric with respect to the normal plane of the surface of the sample to the optical path from the second mirror to the surface of the sample; or, the imaging assembly includes a first collimating mirror and a second focusing mirror, the first detector is located at the rear focal plane of the second focusing mirror; the first mirror and the first focusing mirror are arranged along the incident direction of the first illumination light; the second mirror is located between the first collimating mirror and the second focusing mirror; the first illumination light reflected by the first mirror is parallel light, and the focal length of the first focusing mirror is equal to the focal length of the first collimating mirror; adjusting the first mirror by the adjustment module to make the incident position of the first illumination light on the sample have a first change amount parallel to the converging surface, and adjusting the second mirror to make the conjugate point of the spot of the first detector in the object space have a second change amount parallel to the photosensitive surface of the first detector in the conjugate plane of the object space, and the first change amount is equal to the second change amount, including: adjusting the first mirror and the second mirror by the adjustment module to make the rotation angles of the first mirror and the second mirror the same.

[0128] For the detailed description of the monitoring method of the above monitoring system, refer to the content of the foregoing embodiments and will not be elaborated here.

[0129] The embodiment of the present application provides a working method of an optical system, and the detection method of the optical system includes the monitoring method of the monitoring system provided in the above embodiment. Since the principle of solving problems of this optical system is similar to that of the foregoing monitoring system, the implementation of the monitoring method adopted in this optical system can refer to the implementation of the monitoring method of the foregoing monitoring system, and the repeated parts will not be described again.

[0130] In the embodiments provided in the present disclosure, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architectures, functions, and operations of devices, methods, and computer program products according to multiple embodiments of the present disclosure. In this regard, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the above-mentioned module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than that marked in the accompanying drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, as well as the combination of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system that performs the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0131] It should be noted that in the present disclosure, the term "including", "comprising", or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article, or device including a series of elements not only includes those elements but also includes other elements that are not explicitly listed, or further includes elements inherent to such a process, method, article, or device. Without further limitation, the element limited by the statement "including one..." does not exclude the existence of additional identical elements in the process, method, article, or device including the element.

[0132] Although the disclosed embodiments of the present disclosure are as above, the above content is only an embodiment adopted for the convenience of understanding the present disclosure and is not used to limit the present disclosure. Any person skilled in the art within the technical field to which the present disclosure pertains may make any modifications and changes in the form of implementation and details without departing from the spirit and scope disclosed by the present disclosure. However, the scope of patent protection of the present disclosure shall still be subject to the scope defined by the appended claims.

Claims

1. A monitoring system, characterized in that: include: A first optical component includes a first reflector, wherein the first reflector is used to reflect the first illumination light and make the first illumination light obliquely incident on the sample surface, and the sample surface reflects the first illumination light to form a first signal light; a second optical component, comprising a second reflector, an imaging component and a first detector, wherein the imaging component is used to image the sample surface to the first detector using the first signal light, the first detector is used to obtain a detection image of the sample surface according to the first signal light, and to form a light spot on the photosensitive surface of the first detector, and the second reflector is used to make the light spot formed by the first signal light reflected from the sample surface at a preset calibration position on the photosensitive surface of the first detector be at a preset position; The preset calibration position is the height position of the sample when the sample surface is tested; The adjustment module is used to synchronously adjust the rotation angles of the first reflector and the second reflector relative to the normal plane of the sample surface, so that the first illumination light reflected by the sample at different heights perpendicular to the surface and at the same point along the sample surface forms a first signal light and is collected at the same position of the first detector; the adjustment module is used to make the incident position of the first illumination light on the sample have a first change amount along the direction parallel to the convergence plane, the conjugate point of the light spot of the first detector on the object side has a second change amount along the direction parallel to the photosensitive surface of the first detector in the object side conjugate plane, and the first change amount is equal to the second change amount.

2. The monitoring system according to claim 1, characterized in that: The second reflector is located in the optical path between the imaging assembly and the first detector. The first reflector and the second reflector rotate in opposite directions. The second change is (d 3* ∠2) / M or (d 3* tan∠2) / M, d3 is the distance between the second reflector and the first detector, ∠2 is the rotation angle of the second reflector, and M is the magnification of the imaging component; Alternatively, the second reflector is located in the optical path between the imaging component and the sample, the first reflector and the second reflector rotate in opposite directions, and the second change is d2*∠2 or d 2* tan∠2; d2 is the distance between the second reflector and the object focal plane of the imaging component; Alternatively, the imaging component includes a first collimator and a second focusing lens, wherein the first collimator is used to collimate the first signal light, and the second focusing lens is used to focus the first signal light; The second reflecting mirror is located in the optical path between the first collimating mirror and the second focusing mirror; The first reflector and the second reflector rotate in opposite directions; the second change amount is f2*tan∠2 or f2*∠2, where f2 is the focal length of the first collimator.

3. The monitoring system according to claim 1, characterized in that: The first optical assembly further includes a first focusing mirror, and the first focusing mirror is used to focus the first illumination light; The first reflector and the first focusing mirror are arranged along the incident direction of the first illumination light, and the first illumination light is incident on the first focusing mirror in parallel; the first change amount is f1*tan∠1 or f1*∠1; ∠1 is the rotation angle of the first reflector, and f1 is the focal length of the first focusing mirror; Alternatively, the first focusing mirror and the first reflecting mirror are arranged along the incident direction of the first illumination light, and the first change amount is d1*tan∠1, or d1*∠1, where d1 is the distance from the first reflecting mirror to the converging surface of the first illumination light.

4. The monitoring system according to claim 3, characterized in that: The imaging assembly includes a first collimator and a second focusing mirror, the first detector is located at the rear focal plane of the second focusing mirror; the first reflector and the first focusing mirror are arranged along the incident direction of the first illumination light; the second reflector is located between the first collimator and the second focusing mirror; the first illumination light reflected by the first reflector is parallel light; the first change amount is f1*tan∠1 or f1*∠1, and the second change amount is f2*tan∠2 or f2*∠2.

5. The monitoring system according to claim 4, characterized in that: The focal length of the first focusing mirror is equal to the focal length of the first collimating mirror; the adjustment directions of the first reflecting mirror and the second reflecting mirror are opposite, and the adjustment amounts are the same.

6. The monitoring system according to any one of claims 1 to 5, characterized in that: The optical path from the first reflector to the sample surface is symmetrical with the optical path from the second reflector to the sample surface about a normal plane of the sample surface.

7. The monitoring system according to claim 1, characterized in that: Also includes: A control system is used to determine whether the light spot deviates from a preset position according to the detection image; if so, the control system controls the adjustment module to synchronously adjust the rotation angle of the first reflector and the second reflector relative to the normal plane of the sample surface.

8. A monitoring method applied to the monitoring system according to any one of claims 1 to 7, characterized in that: include: Reflecting the first illumination light through a first reflector and making the first illumination light obliquely incident on a sample surface, wherein the sample surface reflects the first illumination light to form a first signal light; Acquiring a detection image of the sample surface through a second optical component; The sample is monitored and processed according to the detection image, and the monitoring and processing includes: if the light spot deviates from a preset position, the rotation angle of the first reflector and the second reflector relative to the normal plane of the sample surface is synchronously adjusted by an adjustment module, so that the first illumination light reflected by the sample at different heights perpendicular to the surface and at the same point along the sample surface forms a first signal light and is collected at the same position of the first detector.

9. The monitoring method of the monitoring system according to claim 8, characterized in that: Monitoring and processing the sample according to the detection image includes: judging whether the light spot deviates from a preset position according to the detection image; if the light spot deviates from the preset position, determining the rotation direction of the first reflector and the second reflector according to the deviation direction of the light spot from the preset position, and synchronously adjusting the rotation angle of the first reflector and the second reflector relative to the normal plane of the sample surface according to the rotation direction until the light spot is at the preset position.

10. The monitoring method of the monitoring system according to claim 8, characterized in that: There is no reflective element between the first reflector and the sample, and there is no reflective element between the second reflector and the sample surface; or, an even number of reflective elements are provided between the first reflector and the sample, and an even number of reflective elements are provided between the second reflector and the sample surface; Synchronously adjusting the rotation angles of the first reflector and the second reflector relative to the normal plane of the sample surface by the adjustment module includes: synchronously adjusting the first reflector and the second reflector relative to the normal plane of the sample surface in opposite directions by the adjustment module.

11. The monitoring method of the monitoring system according to claim 9, characterized in that: The method further comprises: synchronously adjusting the rotation angles of the first reflector and the second reflector relative to the normal plane of the sample surface by the adjustment module; The first reflector is adjusted by the adjustment module so that the incident position of the first illumination light on the sample has a first change amount along the direction parallel to the converging surface, and the second reflector is adjusted so that the light spot of the first detector at the conjugate point on the object side has a second change amount along the direction parallel to the photosensitive surface of the first detector in the object side conjugate plane, and the first change amount is equal to the second change amount.

12. The monitoring method of the monitoring system according to claim 11, characterized in that: If the optical path from the first reflector to the sample surface is symmetrical with the optical path from the second reflector to the sample surface about the normal plane of the sample surface; Alternatively, the imaging assembly includes a first collimator and a second focusing mirror, the first detector is located at the rear focal plane of the second focusing mirror; the first reflector and the first focusing mirror are arranged along the incident direction of the first illumination light; the second reflector is located between the first collimator and the second focusing mirror; the first illumination light reflected by the first reflector is parallel light, and the focal length of the first focusing mirror is equal to the focal length of the first collimator; The first reflector is adjusted by the adjustment module so that the incident position of the first illumination light on the sample has a first change amount along the direction parallel to the converging surface, and the second reflector is adjusted so that the conjugate point of the first detector light spot on the object side has a second change amount along the direction parallel to the photosensitive surface of the first detector in the object side conjugate plane, and the first change amount is equal to the second change amount, including: adjusting the first reflector and the second reflector by the adjustment module so that the rotation angles of the first reflector and the second reflector are the same.

13. An optical system, characterized in that: include: A monitoring system as claimed in any one of claims 1 to 7; The processing system includes a light source assembly adapted to provide the first illumination light to a first optical assembly.

14. The optical system according to claim 13, characterized in that The first illumination light is also used to form a second signal light after passing through the sample surface; The processing system further includes: a detection module, which is used to collect the second signal light and detect the sample surface according to the second signal light.

15. A method for operating an optical system, characterized in that: include: Providing a first illumination light to the first optical component through the light source component; Using the monitoring method of the monitoring system of any one of claims 8 to 12, the first illumination light reflected from the sample at different heights perpendicular to the surface and at the same point along the sample surface forms the first signal light which is collected at the same position of the first detector; After the monitoring method, the sample is detected by a processing system using the first illumination light.

16. The operating method of the optical system according to claim 15, characterized in that: The first illumination light is also used to form a second signal light after passing through the sample surface; Detecting the sample using the first illumination light by the processing system includes: The second signal light formed by the first illumination light passing through the sample surface is collected by the detection module, and the sample surface is detected according to the second signal light.

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