Defect detection system based on light wavefront

Abstract

This invention discloses a defect detection system based on optical wavefront, comprising a control device, a base, a laser device, a first optical wavefront sensor, and a waveform generator. The base supports the object under test. The laser device, electrically connected to the control device, includes a laser pump and a laser light source. Located on a first side of the object under test, the laser device emits a first laser beam toward the detection area of ​​the object. The first optical wavefront sensor, electrically connected to the control device, receives first reflected light from the first laser beam reflected by the detection area of ​​the object to generate a first reflected light signal, or receives first transmitted light from the first laser beam passing through the detection area of ​​the object to generate a first transmitted light signal. The waveform generator, electrically connected to the control device and the first optical wavefront sensor, receives the first reflected light signal or the first transmitted light signal and generates a first detection waveform.

Description

[Technical Field]

[0001] This invention is a division of Taiwan Patent Application No. 113120751 (application date: June 5, 2024), the full contents of which are incorporated in the patent specification of this invention for reference.

[0002] This invention relates to a defect detection system, and more particularly to a system for detecting defects on an optical wavefront. [Previous Technology]

[0003] Semiconductor manufacturing processes are becoming increasingly sophisticated with technological advancements. Defect detection in wafers and packages is becoming increasingly important. Due to the precision of the manufacturing process, the wafers and packages are numerous and have precise dimensions, making it difficult to detect defects.

[0004] Therefore, how to improve the detection effect and accuracy of the test objects (such as wafers, chips or dies) through the improvement of detection technology, and further provide feedback and improve the process to increase the efficiency of the process, has become one of the important issues that this business aims to solve. [Summary of the Invention]

[0005] The technical problem to be solved by the present invention is to provide a defect detection method based on optical wavefront, which addresses the shortcomings of the prior art. The method includes: placing a test object on a base; providing a laser device, including a laser pump and a laser light source, the laser device being located on a first side of the test object and emitting a first laser beam toward a detection area of ​​the test object; providing a first optical wavefront sensor, the first optical wavefront sensor receiving first reflected light reflected from the detection area of ​​the test object by the first laser beam to generate a first reflected light signal, or receiving first transmitted light from the test object through the detection area of ​​the test object by the first laser beam to generate a first transmitted light signal; and providing a waveform generator electrically connected to the first optical wavefront sensor, the waveform generator receiving the first reflected light signal or the first transmitted light signal to generate a first detection waveform.

[0006] According to a feasible implementation scheme, the defect detection method based on optical wavefront also includes providing a beam splitter, wherein the first reflected light is first split by the beam splitter and then transmitted to the first optical wavefront sensor.

[0007] According to a feasible implementation, the defect detection method based on optical wavefront further includes providing a second optical wavefront sensor, which is located on a second side of the object under test. A first optical wavefront sensor is located on a first side. When the first optical wavefront sensor receives a first reflected light to generate a first reflected light signal, the laser device further emits a second laser beam toward the detection area of ​​the object under test. The second optical wavefront sensor receives a second transmitted light from the second laser beam passing through a portion of the object under test to generate a second transmitted light signal. A waveform generator receives the second transmitted light signal and generates a second detection waveform.

[0008] According to a feasible implementation, the defect detection method based on optical wavefront further includes providing a second optical wavefront sensor electrically connected to a waveform generator, the second optical wavefront sensor being located on a first side of the object under test; a first optical wavefront sensor being located on a second side of the object under test, when the first optical wavefront sensor receives a first transmitted light to generate a first transmitted light signal, the laser device also emits a second laser beam toward the detection portion of the object under test, the second optical wavefront sensor receiving a second reflected light reflected from the detection portion of the second laser beam to generate a second reflected light signal, wherein the waveform generator receives the second reflected light signal and generates a second detection waveform.

[0009] According to a feasible implementation, the wavefront-based defect detection method further includes: providing a laser moving device, connecting a laser device, the laser moving device being used to move the laser device in a three-dimensional space. Providing a first moving device, connecting a first wavefront sensor, the first moving device being used to move the first wavefront sensor in a three-dimensional space.

[0010] According to a feasible implementation, the defect detection method based on optical wavefront further includes providing a second moving device connected to a second optical wavefront sensor, the second moving device being used to move the second optical wavefront sensor in three-dimensional space.

[0011] According to a feasible implementation scheme, the defect detection method based on the light wavefront further includes: providing an imaging device to capture multiple images of the shadow portion of the detection area that has not received the first laser beam and provide them to an analysis module to receive the multiple images and determine and calculate the defects and probabilities of the shadow portion based on the multiple images; or compensating the multiple images and determining and calculating the defects and probabilities of the shadow portion.

[0012] The present invention also provides a system for defect detection based on optical wavefront, comprising a control device, a base, a laser device, a first optical wavefront sensor, and a waveform generator. The base supports the object under test. The laser device is electrically connected to the control device, and includes a laser pump and a laser light source. The laser device is located on a first side of the object under test and emits a first laser beam toward the detection area of ​​the object under test. The first optical wavefront sensor is electrically connected to the control device. The first optical wavefront sensor receives first reflected light reflected from the detection area of ​​the first laser beam to generate a first reflected light signal, or receives first transmitted light passing through the detection area of ​​the first laser beam to generate a first transmitted light signal. The waveform generator is electrically connected to the control device and the first optical wavefront sensor. The waveform generator receives the first reflected light signal or the first transmitted light signal and generates a first detection waveform.

[0013] According to a feasible implementation scheme, the system for defect detection based on optical wavefront also includes a beam splitter, wherein the first reflected light is first split by the beam splitter and then transmitted to the first optical wavefront sensor.

[0014] According to a feasible embodiment, the system for defect detection based on optical wavefront further includes a second optical wavefront sensor, an electrical connection control device, and a waveform generator. The second optical wavefront sensor is located on the second side of the object under test. The first optical wavefront sensor is located on the first side. When the first optical wavefront sensor receives the first reflected light to generate a first reflected light signal, the laser device also emits a second laser beam toward the detection area of ​​the object under test. The second optical wavefront sensor receives the second transmitted light passing through the area of ​​the object under test to generate a second transmitted light signal. The waveform generator receives the second transmitted light signal and generates a second detection waveform.

[0015] According to a feasible embodiment, the system for defect detection based on optical wavefront further includes a second optical wavefront sensor, an electrical connection control device, and a waveform generator. The second optical wavefront sensor is located on a first side of the object under test. The first optical wavefront sensor is located on a second side of the object under test. When the first optical wavefront sensor receives a first transmitted light to generate a first transmitted light signal, the laser device also emits a second laser beam toward the detection area of ​​the object under test. The second optical wavefront sensor receives a second reflected light reflected from the detection area of ​​the object under test by the second laser beam to generate a second reflected light signal. The waveform generator receives the second reflected light signal and generates a second detection waveform.

[0016] According to a feasible embodiment, the system for defect detection based on optical wavefront further includes a laser moving device and a first moving device. The laser moving device is electrically connected to a control device and connected to a laser device, and the laser moving device is used to move the laser device in three-dimensional space. The first moving device is electrically connected to the control device and connected to a first optical wavefront sensor, and the first moving device is used to move the first optical wavefront sensor in three-dimensional space.

[0017] According to a feasible implementation, the system for defect detection based on optical wavefront also includes a second moving device, an electrically connected control device, and a connection to a second optical wavefront sensor, the second moving device being used to move the second optical wavefront sensor in three-dimensional space.

[0018] According to a feasible implementation, the system for defect detection based on optical wavefront further includes an imaging device and a connected control device, the control device including an analysis module. The imaging device captures multiple images of the shadowed area of ​​the detection region that has not received the first laser beam. The analysis module receives the multiple images and determines and calculates the defects and probabilities present in the shadowed area based on the multiple images. Alternatively, it may compensate for multiple images and determine and calculate the defects and probabilities present in the shadowed area.

[0019] One of the beneficial effects of the present invention is that the defect detection method and system based on optical wavefront provided by the present invention can improve the accuracy of defect detection by means of the technical solutions of "a first optical wavefront sensor receiving a first reflected light reflected from a first laser beam through a detection part of the object under test to generate a first reflected light signal, or receiving a first transmitted light through a first laser beam passing through a detection part of the object under test to generate a first transmitted light signal" and "a waveform generator receiving the first reflected light signal or the first transmitted light signal to generate a first detection waveform".

[0020] Furthermore, by setting a second optical wavefront sensor, the user can first use the first detection waveform formed by the reflected light to preliminarily detect whether the object under test contains the above-mentioned defects, and then use the second detection waveform formed by the transmitted light to detect or confirm the detection status of the object under test again, thereby improving the accuracy of the detection results.

[0021] Furthermore, by setting a second light wavefront sensor, the user can first use the first detection waveform formed by the transmitted light to preliminarily detect whether the object under test contains the above-mentioned defects, and then use the second detection waveform formed by the reflected light to re-detect or confirm the detection status of the object under test, thereby improving the accuracy of the detection results.

[0022] To further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are for reference and illustration only and are not intended to limit the present invention.

Implementation Method

[0025] The following specific embodiments illustrate the implementation of the "Defect Detection Method and System Based on Optical Wavefront" disclosed in this invention. Those skilled in the art can understand the advantages and effects of this invention from the content disclosed in this specification. This invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of this invention. Furthermore, the accompanying drawings of this invention are for simple illustrative purposes only and are not depictions of actual dimensions; this is stated in advance. The following embodiments will further describe the relevant technical content of this invention in detail, but the disclosed content is not intended to limit the scope of protection of this invention.

[0026] Please refer to Figure 1, which is a schematic flowchart of a defect detection method 100 based on optical wavefront according to an embodiment of the present invention, which includes steps S10 to S13.

[0027] Step S10: Place the object to be tested on the base.

[0028] Step S11: Provide a laser device, including a laser pump and a laser light source. The laser device is located on the first side of the object to be tested and emits a first laser beam toward the detection area of ​​the object to be tested.

[0029] Step S12: Provide a first optical wavefront sensor, the first optical wavefront sensor receives the first reflected light reflected by the detection part of the first laser beam through the detection part of the object under test to generate a first reflected light signal, or receives the first transmitted light of the first laser beam through the detection part of the object under test to generate a first transmitted light signal.

[0030] Step S13: Provide a waveform generator, electrically connected to the first optical wavefront sensor. The waveform generator receives the first reflected light signal or the first transmitted light signal and generates a first detection waveform.

[0031] According to some embodiments, the base may be a transparent sheet such as glass or sapphire. According to some embodiments, the base is a movable base with a drive motor. According to other embodiments, the base includes a conveyor belt carrying multiple objects to be tested.

[0032] According to some embodiments, the object under test (DUT) may be a wafer, a chip, or a die. According to other embodiments, the DUT may be a package. According to other embodiments, the DUT is located on a substrate (e.g., a circuit board), with the substrate supported by a base. The detection location may be a surface, a hole, a via, or a welded structure; the present invention is not limited in this respect. Through a first detection waveform, the user can determine whether the detection location has defects, such as cracks, uneven surfaces, or detached welded structures, thus identifying the problem causing the defect (e.g., stress concentration) at the defective portion.

[0033] Taking perforated (TGV or TSV) as an example, common defects include burrs on its inner wall surface, unevenness, perforation channel misalignment, incorrect angle between the channel and the substrate, perforation not penetrating the substrate, incorrect size or shape, etc. By detecting the waveform diagram, it is possible to distinguish which of the above categories of defects it may be, and find a solution in the process for the defect.

[0034] According to some embodiments, the wavefront-based defect detection method further includes providing a beam splitter, wherein the first reflected light is first split by the beam splitter and then transmitted to the first wavefront sensor. The difference from the aforementioned method is that in the aforementioned embodiments, the laser beam and the first reflected light are not coaxial, but after setting the beam splitter, the optical path of the first reflected light and the optical path of the laser beam are coaxial. The reflected light after passing through the beam splitter is free of stray light, which makes the light received by the first wavefront sensor purer.

[0035] Please refer to Figure 2, which is a schematic flowchart of a wavefront-based defect detection method 200 according to an embodiment of the present invention. The wavefront-based defect detection method 200 includes steps S20 to S26. In this embodiment, the wavefront-based defect detection method further includes steps S24 and S26, wherein step S24: a second wavefront sensor is provided, which is located on the second side of the object under test. A first wavefront sensor is located on the first side. When the first wavefront sensor receives a first reflected light to generate a first reflected light signal, step S25 is executed: the laser device also emits a second laser beam toward the detection area of ​​the object under test, and the second wavefront sensor receives the second transmitted light passing through the area of ​​the object under test by the second laser beam to generate a second transmitted light signal. Then step S26 is executed: the waveform generator receives the second transmitted light signal and generates a second detection waveform. In this embodiment, the user can first use the first detection waveform formed by reflected light to preliminarily detect whether the object under test contains the above-mentioned defects, and then use the second detection waveform formed by transmitted light to re-detect or confirm the detection status of the object under test, thereby improving the accuracy of the detection results.

[0036] Please refer to Figure 3, which is a schematic flowchart of a wavefront-based defect detection method 300 according to an embodiment of the present invention. The wavefront-based defect detection method 300 includes steps S30 to S36. In this embodiment, step S34: A second wavefront sensor is provided and electrically connected to a waveform generator. The second wavefront sensor is located on a first side of the object under test. A first wavefront sensor is located on a second side of the object under test. When the first wavefront sensor receives a first transmitted light to generate a first transmitted light signal, step S35 is executed: The laser device also emits a second laser beam toward the detection area of ​​the object under test. The second wavefront sensor receives a second reflected light reflected from the detection area of ​​the object under test by the second laser beam to generate a second reflected light signal. Then, step S36 is executed: The waveform generator receives the second reflected light signal and generates a second detection waveform. In this embodiment, the user can first use the first detection waveform formed by transmitted light to preliminarily detect whether the object under test contains the above-mentioned defects, and then use the second detection waveform formed by reflected light to re-detect or confirm the detection status of the object under test, thereby improving the accuracy of the detection results.

[0037] According to some embodiments, the wavefront-based defect detection method further includes: providing a laser moving device, connecting a laser device, the laser moving device being used to move the laser device in three-dimensional space. And providing a first moving device, connected to a first wavefront sensor, the first moving device being used to move the first wavefront sensor in three-dimensional space. In this way, the laser device can be moved and emit a laser beam towards a specific detection area of ​​the object under test. Correspondingly, the first wavefront sensor can also be moved to a position where it can accept a first reflected light or a first transmitted light in response to the laser beam.

[0038] According to some other embodiments, similarly, the wavefront-based defect detection method further includes providing a second moving device connected to a second wavefront sensor, the second moving device being used to move the second wavefront sensor in three-dimensional space. By connecting the second moving device, the second wavefront sensor can be moved to a position to receive second reflected light or second transmitted light.

[0039] Specifically, according to one embodiment, reflective wavefront sensing can be used to detect multiple perforations using a first or second optical wavefront sensor, thereby obtaining relevant information about each perforation. For example, the surface of the perforation can be detected to determine whether the external surface features of the perforation (e.g., the location, shape, and size of the through hole) meet engineering requirements. Alternatively, transmissive wavefront sensing can be used to detect the interior of the perforation to determine the internal surface features of the through hole (e.g., whether cracks or unevenness are present on the internal surface of the perforation). In some embodiments of the present invention, reflective wavefront sensing and transmissive wavefront sensing can also be combined to detect the same detection area.

[0040] According to some embodiments, the wavelength range of the first laser beam and the second laser beam is 300-2000 nm. The pulse width range of the first laser beam and the second laser beam is 50 fs to 50 ns.

[0041] However, the present invention is not limited thereto. The projection angles of the first laser beam and the second laser beam can be adjusted according to the position of the detection site or the material being detected. Furthermore, in some embodiments, the first laser beam and the second laser beam can be adjusted to suitable wavelengths for different materials being detected, thereby improving the accuracy of the detection.

[0042] Referring again to Figure 1, this embodiment further includes steps S14 and S15. Step S14: An imaging device is provided to capture multiple images of the shadowed area of ​​the detection region that has not received the first laser beam. Step S15: An analysis module is provided to receive the multiple images and determine and calculate the defects and probabilities of the shadowed area based on the multiple images; or to compensate the multiple images and determine and calculate the defects and probabilities of the shadowed area. The imaging device is any device capable of capturing images, specifically capturing the shadowed area (detection region) of the object under test, particularly the area that cannot receive the first laser beam (or the second laser beam). The analysis module is, for example, a computer, which can determine the possible defects of the shadowed area and the probability of such defects occurring through deep learning. The analysis module may further determine and calculate the defects and probabilities of the shadowed area by compensating the images.

[0043] Please refer to Figure 4, which is a schematic diagram of the architecture of a wavefront-based defect detection system Z1 according to an embodiment of the present invention. The wavefront-based defect detection system Z1 includes a control device 1, a base 2, a laser device 3, a first wavefront sensor 4, and a waveform generator 5. The base 2 supports the object under test 6. The laser device 3 is electrically connected to the control device 1. The laser device 3 includes a laser pump 31 and a laser light source 32. The laser device 3 is located on the first side S1 of the object under test 6 and emits a first laser beam toward the detection area of ​​the object under test 6. The first wavefront sensor 4 is electrically connected to the control device 1. The first wavefront sensor 4 receives the first reflected light R1 reflected from the detection area of ​​the object under test 6 by the first laser beam to generate a first reflected light signal. The waveform generator 5 is electrically connected to the control device 1 and the first wavefront sensor 4. The waveform generator 5 receives the first reflected light signal and generates a first detection waveform.

[0044] Please refer to the above description regarding the base 2, the object to be tested 6, the detection location, and the first detection waveform.

[0045] Please refer to Figure 5, which shows a defect detection system Z2 based on optical wavefront according to an embodiment of the present invention. The difference between this system and the embodiment shown in Figure 4 is that the first optical wavefront sensor 4 receives the first transmitted light L1 of the first laser beam passing through the detection part of the object under test 6 to generate a first transmitted light signal. The waveform generator 5 receives the first transmitted light signal and generates a first detection waveform.

[0046] Please refer to Figure 6, which shows a wavefront-based defect detection system Z3 according to an embodiment of the present invention. In this embodiment, the wavefront-based defect detection system further includes a beam splitter 7. The first reflected light R1 is first split by the beam splitter 7 and then transmitted to the first wavefront sensor 4. In this way, a stray light beam can be transmitted to the first wavefront sensor 4, making the sensing more accurate.

[0047] Please refer to Figure 7, which shows a wavefront-based defect detection system Z4 according to an embodiment of the present invention. In this embodiment, the wavefront-based defect detection system Z4 further includes a second wavefront sensor 8, an electrical connection control device 1, and a waveform generator 5. The second wavefront sensor 8 is located on the second side S2 of the object under test 6. The first wavefront sensor 4 is located on the first side S1. When the first wavefront sensor 4 receives the first reflected light R1 to generate a first reflected light signal, the laser device 3 also emits a second laser beam toward the detection area of ​​the object under test 6. The second wavefront sensor 8 receives the second transmitted light L2 passing through the detection area of ​​the object under test 6 to generate a second transmitted light signal. The waveform generator 5 receives the second transmitted light signal and generates a second detection waveform. In this embodiment, the user can first preliminarily detect whether the object under test 6 contains the above-mentioned defects by using the first detection waveform formed by the reflected light, and then re-detect or confirm the detection status of the object under test 6 based on the second detection waveform formed by the transmitted light, thereby improving the accuracy of the detection results.

[0048] Please refer to Figure 8, which shows a wavefront-based defect detection system Z5 according to an embodiment of the present invention. According to this embodiment, the wavefront-based defect detection system further includes a second wavefront sensor 8, an electrical connection control device 1, and a waveform generator 5. The second wavefront sensor 8 is located on the first side S1 of the object under test 6. The first wavefront sensor 4 is located on the second side S2 of the object under test 6. When the first wavefront sensor 4 receives the first transmitted light L1 to generate a first transmitted light signal, the laser device 3 also emits a second laser beam toward the detection area of ​​the object under test 6. The second wavefront sensor 8 receives the second reflected light R2 reflected by the second laser beam through the detection area of ​​the object under test 6 to generate a second reflected light signal. The waveform generator 5 receives the second reflected light signal and generates a second detection waveform. In this embodiment, the user can first use the first detection waveform formed by transmitted light to preliminarily detect whether the object under test 6 contains the above-mentioned defects, and then use the second detection waveform formed by reflected light to re-detect or confirm the detection status of the object under test 6, thereby improving the accuracy of the detection results.

[0049] According to some embodiments, the system for defect detection based on optical wavefront also includes a laser moving device and a first moving device (not shown). The laser moving device is electrically connected to the control device 1 and to the laser device 3, and is used to move the laser device 3 in three-dimensional space. The first moving device is electrically connected to the control device 1 and to the first optical wavefront sensor 4, and is used to move the first optical wavefront sensor 4 in three-dimensional space. In this way, the laser device 3 can move in three-dimensional space and emit a laser beam for a specific detection area of ​​the object 6 under test. Correspondingly, the first optical wavefront sensor 4 can also be moved to a position that can accept the first reflected light R1 or the first transmitted light L1 in response to the laser beam.

[0050] According to some other embodiments, the system for defect detection based on optical wavefronts further includes a second moving device (not shown), electrically connected to the control device 1 and connected to the second optical wavefront sensor 8. The second moving device is used to move the second optical wavefront sensor 8 in three-dimensional space. By connecting the second moving device, the second optical wavefront sensor 8 can be moved to a position to receive the second reflected light R2 or the second transmitted light L2.

[0051] According to some embodiments, the system for defect detection based on light wavefront further includes an imaging device (not shown). The imaging device is connected to a control device, which includes an analysis module (not shown). The imaging device captures multiple images of the shadowed portion of the detection area that does not receive the first laser beam. The analysis module receives the multiple images and determines and calculates the defects and probabilities present in the shadowed portion based on the multiple images. The analysis module may also compensate for the multiple images and determine and calculate the defects and probabilities present in the shadowed portion. The imaging device can be any device capable of capturing images (such as a camera), capturing the shadowed portion of the detection area of ​​the object under test, particularly the portion that cannot receive the first laser beam (or the second laser beam). The analysis module, such as a computer, can determine the possible defects in the shadowed portion and the probability of such defects occurring through deep learning. The analysis module may further determine and calculate the defects and probabilities present in the shadowed portion by compensating the images. With this configuration, the accuracy of defect detection can be improved.

[0052] It should be noted that the wavelength of the laser beam emitted by the laser device 3 of the present invention can be adjusted according to the detection distance (the distance between the laser device 3 and the object to be tested 6) and the characteristics of the part to be detected (such as the above-mentioned cracks, holes, perforations, bonds, uneven surfaces, etc.). The present invention is not limited to this.

[0053] It should also be noted that, according to some embodiments, the base 2 is a penetrable platform, so that the first penetrating light L1 and the second penetrating light L2 can pass through without being affected by the base 2.

[0054] It should also be noted that in some embodiments, the first laser beam and the second laser beam may be distinguished as the same laser beam or different laser beams, depending on the material of the object to be tested 6 or the location of the detection part.

[0055] [Beneficial Effects of the Embodiments]

[0056] One of the beneficial effects of the present invention is that the defect detection method and system based on optical wavefront provided by the present invention can improve the accuracy of defect detection results by means of the technical solutions of "a first optical wavefront sensor receiving a first reflected light reflected from a first laser beam through a detection part of the object under test to generate a first reflected light signal, or receiving a first transmitted light through a first laser beam passing through a detection part of the object under test to generate a first transmitted light signal" and "a waveform generator receiving the first reflected light signal or the first transmitted light signal to generate a first detection waveform".

[0057] Furthermore, by setting a second light wavefront sensor, the user can first use the first detection waveform formed by the reflected light to preliminarily detect whether the object under test contains the above-mentioned defects, and then use the second detection waveform formed by the transmitted light to detect or confirm the detection status of the object under test again, thereby improving the accuracy of the detection results.

[0058] Furthermore, by setting a second light wavefront sensor, the user can first use the first detection waveform formed by the transmitted light to preliminarily detect whether the object under test contains the above-mentioned defects, and then use the second detection waveform formed by the reflected light to re-detect or confirm the detection status of the object under test, thereby improving the accuracy of the detection results.

[0059] The content disclosed above is only a preferred and feasible embodiment of the present invention, and is not intended to limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made using the contents of the present invention specification and drawings are included in the scope of the patent application of the present invention. [Simplified Explanation of the Diagram]

[0023] Figures 1 to 3 are schematic flowcharts of a defect detection method based on optical wavefront according to an embodiment of the present invention.

[0024] Figures 4 to 8 are schematic diagrams of the system architecture for defect detection based on optical wavefront according to an embodiment of the present invention.

Claims

1. A system for defect detection based on optical wavefront, comprising: A control device, the control device including an analysis module; A base that supports an object to be tested located on a substrate; A laser device electrically connected to the control device, the laser device including a laser pump and a laser light source, the laser device being located on a first side of the object under test, emitting a first laser beam toward a detection portion of the object under test, the first laser beam projected onto the object under test located on the substrate being reflected; a first optical wavefront sensor electrically connected to the control device, the first optical wavefront sensor receiving a first reflected light from the first laser beam reflected by the detection portion of the object under test to generate a first reflected light signal; a waveform generator electrically connected to the control device and the first optical wavefront sensor, the waveform generator receiving the first reflected light signal to generate a first detection waveform; and an imaging device connected to the control device; wherein, the imaging device captures multiple images of a shadow portion of the detection portion that did not receive the first laser beam, and the analysis module receives multiple images. Specifically, the defects and probabilities of the shadow area are determined and calculated based on multiple images; or multiple images are compensated, and the defects and probabilities of the shadow area are determined and calculated.

2. The system for defect detection based on optical wavefront as described in claim 1 further includes a beam splitter, wherein the first reflected light is first split by the beam splitter and then transmitted to the first optical wavefront sensor.

3. The system for defect detection based on optical wavefront as described in claim 1 further includes a second optical wavefront sensor electrically connected to the control device and the waveform generator, wherein the second optical wavefront sensor is located on a second side of the object under test.

4. The system for defect detection based on optical wavefront as described in claim 1 further includes a second optical wavefront sensor electrically connected to the control device and the waveform generator, the second optical wavefront sensor being located on the first side of the object under test; the laser device further emits a second laser beam toward the detection portion of the object under test, and the second optical wavefront sensor receives a second reflected light reflected from the second laser beam at the detection portion of the object under test to generate a second reflected light signal, wherein... The waveform generator receives the second reflected light signal and generates a second detection waveform.

Images