Method and device for detecting postures of wafers in wafer box

Abstract

The invention relates to the technical field of automatic detection and control of semiconductor manufacturing, in particular to a method and a device for detecting postures of wafers in a wafer box. According to the method provided by the invention, double light sources are adopted to irradiate the two sides of the wafer to form bright spots, and the number of the wafers in the wafer box is calculated by analyzing the width and position of the bright spots and the center deviation information of the bright spots in the left area and the right area, so that accurate detection of the positions of the wafers is realized, and the problem of wafer lamination or dislocation is judged; the wafer posture detection device realizes accurate detection of the number and position of wafers with different sizes and shapes in wafer boxes with different poses, can improve the detection precision and efficiency, improves the production automation level, effectively solves the problem that the wafers are easy to misplace in the semiconductor production process, fills the blank of wafer posture detection in the wafer box, and improves the production efficiency. The method has great technical advantages, market prospect and application value.

Description

Technical Field

[0001] The present invention relates to the technical field of automated detection and control of semiconductor manufacturing, and in particular to a method and device for detecting the posture of a wafer in a wafer box. Background Art

[0002] In the semiconductor manufacturing process, accurate detection of the number and position of wafers in a wafer box is crucial to ensuring production quality and efficiency. Traditional manual inspection methods have problems such as low efficiency and high error rate, especially in large-scale production environments, where manual inspection is difficult to meet the requirements of high accuracy and high speed.

[0003] With the development of automation technology, accurate detection of the number and position of wafers has become a necessity, but the existing detection methods still have certain limitations in detection accuracy and applicability. Traditional visual inspection methods usually adopt a single light source and single-point detection. This method is easily affected by ambient light and other interference factors, resulting in unstable detection results. Especially when dealing with complex situations (such as wafer stacking or tilting), it is often difficult to accurately judge the exact number and actual position of the wafer. Another common laser detection method is to use laser technology to perform high-precision spatial measurement and position detection of the number and position of wafers. In addition to the high cost problem, this method has poor adaptability to the system environment. When detecting wafer stacking, it is difficult to accurately distinguish the specific position of the wafer. Summary of the invention

[0004] In order to overcome the defect that the laser detection system in the above-mentioned prior art cannot identify the wafer posture in the wafer box, the present invention proposes a method for detecting the wafer posture in a wafer box, which realizes the accurate detection of the number and position of wafers of different sizes and shapes in wafer boxes with different postures, thereby ensuring high efficiency of wafer management and production.

[0005] The present invention proposes a method for detecting the posture of wafers in a wafer box, which comprises setting two light sources that do not block each other, irradiating light beams from above the wafer box to both sides of the wafer box respectively, and each light source forms a bright spot close to the corresponding light source on the wafer in the wafer box; an image of the wafer box is photographed from above the wafer box, and then the number and posture of the wafers in each tooth groove in the wafer box are identified according to the size of the bright spot on the wafer box image and the relative positions of the bright spots corresponding to different light sources on the same wafer.

[0006] Preferably, the method for identifying the wafer posture according to the bright spots on the wafer box image comprises the following steps:

[0007] First, the bright spots are extracted from the wafer box image, and the corresponding relationship between the bright spots and the light sources is identified; the area where the bright spots corresponding to the light sources on one side are located is taken as the main area, and the area where the bright spots corresponding to the light sources on the other side are located is taken as the auxiliary area; the length direction on the wafer box image is taken as parallel to the wafer, and the width direction is taken as perpendicular to the wafer; the distance between the maximum bright spot in the main area and the maximum bright spot in the auxiliary area in the length direction of the wafer image is taken as the area interval;

[0008] Then, a recognition algorithm is used to extract bright spots from the wafer box image, and the length of the detection frame is greater than the length value of the longest bright spot in the main area; the width of the detection frame is determined according to the scaling state of the tooth groove where the bright spot is located;

[0009] The detection frame in the main area is translated to the auxiliary area along the length direction of the wafer image by a distance as an auxiliary frame, and the number and posture of wafers in the tooth groove corresponding to the detection frame are determined by combining the corresponding detection frame and the auxiliary frame.

[0010] Preferably, for the bright spot Q in the detection frame, obtain the bright spot Q' in the auxiliary frame that is closest to the bright spot Q in the width direction of the wafer box, and let the bright spot Q and the bright spot Q' be a bright spot pair, and the distance between the center points of the two be the position difference;

[0011] The rule for judging the number and posture of wafers in the corresponding tooth slot of the detection frame by combining the corresponding detection frame and auxiliary frame is as follows:

[0012] When there is a bright spot in the detection frame:

[0013] If the width of the bright spot is less than or equal to the set value a, and the position difference is less than the set value b, it is judged that there is a wafer in the tooth groove and it is placed normally;

[0014] If the width of the bright spot is less than or equal to the set value a, and there is no bright spot in the auxiliary frame, it is determined that there is a wafer in the tooth groove and it is placed tilted;

[0015] If the width of the bright spot is greater than the set value a, and the position difference is less than the set value b, it is judged that two wafers overlap in the tooth slot and are placed normally;

[0016] If the width of the bright spot is greater than the set value a, and there is no bright spot in the auxiliary frame, it is determined that two wafers overlap and are tilted in the tooth groove;

[0017] When there are 2 bright spots in the detection frame and 2 bright spots in the auxiliary frame L'n, it is judged that there are two wafers overlapping in the tooth slot and they are placed normally;

[0018] When there are two bright spots in the detection frame and no bright spots in the auxiliary frame, it is judged that there are two wafers overlapping and tilted in the broken tooth groove;

[0019] When there are two bright spots in the detection frame and one bright spot in the auxiliary frame, it is determined that there are two wafers in the tooth slot, one of which is placed normally and the other is placed tilted.

[0020] Preferably, a is greater than or equal to the thickness of a single wafer and less than or equal to the thickness of two wafers; b is greater than 0 and less than the width of a single tooth groove.

[0021] Preferably, when there is a bright spot in the main area of ​​the nth tooth groove of the wafer box, the width of the detection frame corresponding to the bright spot is W0×Hn, wherein W0 is a set value; Hn is the width factor of the nth tooth groove, which is the ratio of the width of the nth tooth groove on the wafer box image to the standard tooth groove width.

[0022] Preferably, W0 is between 1 and 2 times the tooth groove width.

[0023] Preferably, after taking an image of the wafer box from above the wafer box, the wafer box image is first adjusted so that the length direction of the wafer box in the wafer box image is in the horizontal direction; then, the bright spot area is extracted in combination with threshold segmentation, and the bright spot area is morphologically processed to extract the bright spot information; and then, the number and posture of wafers in each tooth groove in the wafer box are identified based on the bright spot size on the wafer box image and the relative positions of the bright spots corresponding to different light sources on the same wafer.

[0024] A wafer detection device proposed in the present invention includes: a first light source, a second light source, a visual sensor, a processor, and a station for placing a wafer box;

[0025] The visual sensor is arranged directly above the workstation for photographing the wafer box; the first light source and the second light source are both bar-shaped light sources and are relatively arranged on both sides of the visual sensor, the first light source and the second light source are parallel to each other and perpendicular to the wafer plane in the wafer box, and the light emitting directions of the first light source and the second light source are both vertically downward; and the projection of the light emitting surface of the first light source on the horizontal plane and the projection of the light emitting surface of the second light source on the horizontal plane are both located in the wafer box;

[0026] The processor is connected to the visual sensor and is used to process the image collected by the visual sensor to implement the wafer posture detection method in the wafer box and determine the placement posture of the wafer in each tooth groove in the wafer box.

[0027] Preferably, the first light source and the second light source are both bar-shaped light sources.

[0028] Preferably, the first light source and the second light source are the same light source, and the light emitting surfaces both cover the wafer box in the width direction of the wafer box.

[0029] The advantages of the present invention are:

[0030] (1) The present invention proposes a method for detecting the posture of wafers in a wafer box. The method uses dual light sources to illuminate both sides of the wafer to form bright spots. By analyzing the width, position and center deviation of the bright spots in the left and right areas, the method calculates the number of wafers in the wafer box, realizes accurate detection of the wafer position, and determines the problem of wafer stacking or misalignment. The method realizes accurate detection of the number and position of wafers of different sizes and shapes in wafer boxes with different postures, can improve detection accuracy and efficiency, improve the level of production automation, effectively solve the problem of easy misplacement of wafers in the semiconductor production process, fills the gap in wafer posture detection in wafer boxes, and has great technical advantages, market prospects and application value.

[0031] (2) This application extracts bright spot area information through image processing, divides the tooth groove, calculates the number of wafers according to the number and width information of bright spots in the detection frame; realizes the position detection function according to the center position offset information of the corresponding detection frame and auxiliary frame; effectively solves the problem that the wafer size is too large and the specific placement of each tooth groove cannot be clearly photographed, and at the same time eliminates the influence of camera distortion on the detection results, improves the detection accuracy of the number and placement of wafers, and further realizes the detection of the wafer placement state. The present invention realizes an efficient, accurate and adaptable method for detecting the number and position of wafers in a wafer box, realizes accurate detection of the number and position of wafers of different sizes and shapes in wafer boxes with different postures, and ensures high efficiency of wafer management and production.

[0032] (3) The wafer detection device proposed in the present invention can monitor and adjust in real time and adapt to wafer boxes of different specifications and states, so as to realize accurate detection of the number and position of wafers of conventional and special shapes; it can be integrated into an automatic production line to improve the automation and intelligence level of the semiconductor manufacturing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A flow chart of a wafer posture method in a wafer box;

[0034] Figure 2 is a schematic diagram of a wafer inspection device;

[0035] Figure 3 Schematic diagram of image area division;

[0036] Figure 4 A spatial diagram of a wafer inspection device in an embodiment;

[0037] Figure 5 This is a physical picture of the wafer placement in the embodiment;

[0038] Figure 6 This is a physical diagram of wafer placement in another embodiment.

[0039] Illustration: 1-wafer box; 2-wafer; 3-light source; 4-camera; 5-computer. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] Reference Figure 1 , a method for detecting the posture of a wafer in a wafer box proposed in the present application comprises the following steps:

[0042] S1. Reference Figure 2 , two light sources are arranged in parallel above the wafer box to illuminate the wafer box and form bright spots on the wafer.

[0043] In this embodiment, the plane of the light beam emitted by the light source is parallel to the width direction of the wafer box, that is, the plane of the light beam is perpendicular to the plane of the wafer in the wafer box; the light source is used to illuminate the wafer box and form a bright spot on the side of the wafer close to the light source; a camera for photographing the wafers in the wafer box is arranged directly above the wafer box;

[0044] In this embodiment, in order to ensure that the illumination areas of the two light sources do not overlap, the two light sources can be respectively arranged close to the two sides of the wafer box, so that the bright spots illuminated by the light sources on the wafer are respectively close to the two ends of the wafer.

[0045] S2, turn on two light sources, each light source forms a bright spot corresponding to the position on the wafer; the bright spots formed by the same light source on different wafers form a bright spot string parallel to the width direction of the wafer box; collect the wafer box image by the camera and adjust the image so that the length direction of the wafer box in the wafer box image, that is, the tooth groove direction, is in the horizontal direction; let the area where the bright spot of the light source on one side is located be the main area, and the area where the bright spot of the light source on the other side is located be the auxiliary area; the main area is area A shown in the figure, and the auxiliary area is area B shown in the figure; let the brightness with the largest length in the main area A be the reference bright spot, let the brightness with the largest length in the auxiliary area B be the auxiliary bright spot, and calculate the distance between the reference bright spot and the auxiliary two points in the length direction of the wafer box as the area interval d;

[0046] S3, using a recognition algorithm to identify the bright spot in the adjusted wafer box image, the length of each detection frame is a multiple of the length of the reference bright spot, such as 2 times; Figure 3 , let the detection frame marking the bright spot in the nth tooth groove in the main area A of the wafer box be recorded as Ln, let the starting coordinate of Ln in the width direction of the wafer box be C(0,n), the end coordinate of Ln in the width direction of the wafer box be Cn, and the size of Ln in the width direction of the wafer box be Wn;

[0047] Then: Wn = W0 × Hn

[0048] Cn = C(0,n) + Wn

[0049] Wherein, W0 is a set value, which can be specifically set to a value between 1 times and 2 times the tooth groove width, for example, 1.5 times the tooth groove width; Hn is the width factor of the nth tooth groove, which can be specifically set to the ratio of the width of the nth tooth groove on the wafer cassette image to the standard tooth groove width.

[0050] S4. Set a width threshold a and a distance threshold b; a is greater than or equal to the thickness of a single wafer and less than or equal to the thickness of two wafers; b is greater than 0 and less than the width of a single tooth groove; when Ln is translated a distance d along the length direction of the wafer cassette and is located on the auxiliary area B, it is denoted as the auxiliary frame L'n, and the wafer posture in the nth tooth groove in the main area A is judged in combination with the following rules;

[0051] When there are bright spots in both the detection frame Ln and the auxiliary frame L'n, for the bright spot Q in the detection frame Ln, obtain the bright spot Q' in the auxiliary frame L'n that is closest to the bright spot Q in the wafer cassette width direction, and let the bright spot Q and the bright spot Q' be a pair of bright spots, and the distance between the center points of the two is used as the position difference;

[0052] When there is only one bright spot in the detection frame Ln, let the width of the bright spot in the detection frame Ln be denoted as xn; the position difference corresponding to the bright spot in the detection frame Ln is denoted as ΔXn;

[0053] When xn ≤ a and ΔXn < b, it is judged that there is one wafer in the nth tooth groove and it is placed normally; placed normally means that the wafer plane is parallel to the length direction of the wafer cassette;

[0054] When xn ≤ a and there is no bright spot in the auxiliary frame L'n, it is judged that there is one wafer in the nth tooth groove and it is placed obliquely; placed obliquely means that the wafer plane is inclined to the length direction of the wafer cassette;

[0055] When xn > a and ΔXn < b, it is judged that there are two wafers overlapping in the nth tooth groove and they are placed normally;

[0056] When xn > a and there is no bright spot in L'n, it is judged that there are two wafers overlapping in the nth tooth groove and they are placed obliquely;

[0057] When there are 2 bright spots in the detection frame Ln and there are also two bright spots in the auxiliary frame L'n, it is judged that there are two wafers overlapping in the nth tooth groove and they are placed normally;

[0058] When there are 2 bright spots in the detection frame Ln and there is no bright spot in the auxiliary frame L'n, it is judged that there are two wafers overlapping in the nth tooth groove and they are placed obliquely;

[0059] When there are two bright spots in the detection frame Ln and only one bright spot in the auxiliary frame L'n, it is determined that there are two wafers in the nth tooth slot, one of which is placed normally and the other is placed tilted.

[0060] In the above step S2, the number of bright spots is first counted according to the bright spots in the main area A; for each bright spot in the main area, when its width is less than a, it is determined that the bright spot corresponds to one wafer; when its width is greater than a, the bright spot corresponds to two wafers.

[0061] In order to improve the accuracy of identifying bright spots using the recognition algorithm in step S3, the wafer box image is first processed in step S2, including image preprocessing, rotating the image to keep the tooth groove level, threshold segmenting the image to extract the bright spot area, and then performing morphological processing on the bright spot area, such as closing operation or expansion operation, to obtain accurate bright spot information, so as to facilitate the subsequent recognition algorithm to identify the bright spot and improve the labeling accuracy of the detection frame. The recognition algorithm can use an existing target detection algorithm, such as the YOLOv series algorithm.

[0062] A wafer inspection device comprises: a first light source, a second light source, a visual sensor, a processor and a station for placing a wafer box;

[0063] The first light source and the second light source are both bar-shaped light sources and are arranged on two sides of the workstation opposite to each other. The light emitting directions of the first light source and the second light source are both parallel to the wafers in the wafer box.

[0064] The visual sensor is set just above the workstation to photograph the wafer box;

[0065] The processor is connected to the visual sensor and is used to process the image collected by the visual sensor to implement the wafer posture detection method in the wafer box as described above, and determine the placement posture of the wafer in each tooth groove in the wafer box.

[0066] The above-mentioned wafer detection device and wafer posture detection method in a wafer box are explained and verified in combination with specific embodiments below.

[0067] The wafer inspection device in this embodiment includes a bar light source 3, a camera 4 and a computer 5 as a processor. Two bar light sources 3 and the camera 4 are installed above the wafer box 1, and the two bar light sources 3 are arranged on opposite sides of the camera.

[0068] The wafer box 1 is a base type with a size of 320×250mm, 25 teeth and grooves, and an interval of 10mm between adjacent teeth and grooves; the wafer 2 is 12 inches in size and 0.4mm in thickness; the strip light source 3 uses a direct light source with a length of 400mm to ensure normal reflection at the edge of the wafer to form a bright spot; the camera 5 uses a 50-megapixel area array camera with a single pixel accuracy of 0.05mm.

[0069] The strip light sources 3 are symmetrically mounted on both sides of the wafer box 1. Uniform illumination is formed by adjusting the light emitting angle of the strip light sources 3, ensuring that clearly visible bright spots are formed symmetrically on both sides of the edges of the wafer 2 in the wafer box.

[0070] The camera 4 has high resolution and is located directly above the wafer box 2 , and is used to capture the distribution of bright spots at the edge of the wafer 2 inside the wafer box 1 .

[0071] The computer 5 receives the wafer box image transmitted by the camera and processes it.

[0072] In this embodiment, the computer first adjusts the angle of the wafer box image, takes the tooth groove at the edge of the wafer box 1 as the reference line, and rotates the image 5 to make the reference line horizontal. In this way, the wafer box on the wafer box image can be placed approximately horizontally and vertically, and the bright spot strings corresponding to the same light source are approximately distributed on a vertical line perpendicular to the reference line, which is convenient for bright spot extraction.

[0073] In this embodiment, after the computer 5 adjusts the wafer box image, it executes the wafer posture detection method in the wafer box shown in the above steps S1-S4, and calculates the number of wafers 2 in the wafer box 1 by analyzing the position and width of the bright spots on both sides of the edge of the wafer 2 and the offset of the center position of the bright spots on both sides, and determines the misplacement problems such as stacking or misalignment of the wafer 2.

[0074] In this embodiment, first Figure 5 As shown, wafers are placed in wafer box 1. According to the algorithm setting, the area corresponding to the bright spot string on the lower side of the image is the main area, and the area corresponding to the bright spot string on the upper side of the image is the auxiliary area. In this embodiment, the detection results of the detection method proposed in this application are: the wafer in slot 1 is placed normally, two wafers overlap and are placed normally in slot 2, and single wafers are placed tilted in slots 3 and 4; there are no wafers in slots 5-25.

[0075] Normal placement means that both ends of the wafer are located in the same tooth groove; tilted placement means that both ends of the wafer are located in different tooth grooves.

[0076] In this embodiment, further Figure 6 The wafers are placed as shown, and the algorithm settings are as follows Figure 5 Embodiment; Then the detection results of the detection method proposed in this application are: the wafers in slots 1 and 3 are placed normally, there are 2 wafers overlapping and placed normally in slot 2, the wafer in slot 4 is placed tilted; there are no wafers in slots 5-25.

[0077] It can be seen that in this embodiment, the wafer posture can be correctly identified under both placement modes, which proves that the present application can identify the number and posture of wafers in the wafer box.

[0078] Of course, it is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, but also includes the same or similar structures that can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any reference numerals in the claims should not be regarded as limiting the claims involved.

[0079] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0080] The techniques, shapes, and structural parts not described in detail in the present invention are all well-known techniques.

Claims

1. A method for detecting the posture of a wafer in a wafer box, characterized in that: Two light sources that do not block each other are set up, and light beams are irradiated from above the wafer box to both sides of the wafer box respectively. Each light source forms a bright spot close to the corresponding light source on the wafer in the wafer box; the wafer box image is taken from above the wafer box, and then the number and posture of the wafers in each tooth groove in the wafer box are identified according to the size of the bright spot on the wafer box image and the relative positions of the bright spots corresponding to different light sources on the same wafer.

2. The method for detecting the wafer posture in a wafer box according to claim 1, characterized in that: The method for identifying the wafer posture according to the bright spots on the wafer box image comprises the following steps: First, the bright spots are extracted from the wafer box image, and the corresponding relationship between the bright spots and the light sources is identified; the area where the bright spots corresponding to the light sources on one side are located is taken as the main area, and the area where the bright spots corresponding to the light sources on the other side are located is taken as the auxiliary area; the length direction on the wafer box image is taken as parallel to the wafer, and the width direction is taken as perpendicular to the wafer; the distance between the maximum bright spot in the main area and the maximum bright spot in the auxiliary area in the length direction of the wafer image is taken as the area interval; Then, a recognition algorithm is used to extract bright spots from the wafer box image, and the length of the detection frame is greater than the length value of the longest bright spot in the main area; the width of the detection frame is determined according to the scaling state of the tooth groove where the bright spot is located; The detection frame in the main area is translated to the auxiliary area along the length direction of the wafer image by a distance as an auxiliary frame, and the number and posture of wafers in the tooth groove corresponding to the detection frame are determined by combining the corresponding detection frame and the auxiliary frame.

3. The method for detecting the wafer posture in a wafer box according to claim 2, characterized in that: For the bright spot Q in the detection frame, obtain the bright spot Q' in the auxiliary frame that is closest to the bright spot Q in the width direction of the wafer box, and let the bright spots Q and Q' be a bright spot pair, and the distance between the center points of the two be the position difference; The rule for judging the number and posture of wafers in the corresponding tooth slot of the detection frame by combining the corresponding detection frame and auxiliary frame is as follows: When there is a bright spot in the detection frame: If the width of the bright spot is less than or equal to the set value a, and the position difference is less than the set value b, it is judged that there is a wafer in the tooth groove and it is placed normally; If the width of the bright spot is less than or equal to the set value a, and there is no bright spot in the auxiliary frame, it is determined that there is a wafer in the tooth groove and it is placed tilted; If the width of the bright spot is greater than the set value a, and the position difference is less than the set value b, it is judged that two wafers overlap in the tooth slot and are placed normally; If the width of the bright spot is greater than the set value a, and there is no bright spot in the auxiliary frame, it is determined that two wafers overlap and are tilted in the tooth groove; When there are 2 bright spots in the detection frame and 2 bright spots in the auxiliary frame L'n, it is judged that there are two wafers overlapping in the tooth slot and they are placed normally; When there are two bright spots in the detection frame and no bright spots in the auxiliary frame, it is judged that there are two wafers overlapping and tilted in the broken tooth groove; When there are two bright spots in the detection frame and one bright spot in the auxiliary frame, it is determined that there are two wafers in the tooth slot, one of which is placed normally and the other is placed tilted.

4. The method for detecting the wafer posture in a wafer box according to claim 3, characterized in that: a is greater than or equal to the thickness of a single wafer and less than or equal to the thickness of two wafers; b is greater than 0 and less than the width of a single tooth groove.

5. The method for detecting the posture of wafers in a wafer box according to claim 2, characterized in that: When there is a bright spot in the main area of ​​the nth tooth groove of the wafer box, the width of the detection frame corresponding to the bright spot is W0×Hn, where W0 is the set value; Hn is the width factor of the nth tooth groove, which is the ratio of the width of the nth tooth groove on the wafer box image to the standard tooth groove width.

6. The method for detecting the posture of a wafer in a wafer box as claimed in claim 45, characterized in that: W0 is a value between 1 and 2 times the tooth width.

7. The method for detecting the posture of wafers in a wafer box according to claim 1, characterized in that: After taking the wafer box image from above the wafer box, the wafer box image is first adjusted so that the length direction of the wafer box in the wafer box image is in the horizontal direction; then the bright spot area is extracted by combining threshold segmentation, and the bright spot area is morphologically processed to extract the bright spot information; then the number and posture of wafers in each tooth groove in the wafer box are identified according to the bright spot size on the wafer box image and the relative position of the bright spots corresponding to different light sources on the same wafer.

8. A wafer inspection device, characterized in that: include: A first light source, a second light source, a visual sensor, a processor, and a station for placing a wafer box; The visual sensor is set just above the workstation to photograph the wafer box; The first light source and the second light source are both bar-shaped light sources and are relatively arranged on both sides of the visual sensor. The first light source and the second light source are parallel to each other and perpendicular to the wafer plane in the wafer box. The light emitting directions of the first light source and the second light source are both vertically downward; and the projection of the light emitting surface of the first light source on the horizontal plane and the projection of the light emitting surface of the second light source on the horizontal plane are both located in the wafer box; The processor is connected to the visual sensor and is used to process the image collected by the visual sensor to implement the wafer posture detection method in the wafer box as described in any one of claims 1-7, and determine the placement posture of the wafer in each tooth groove in the wafer box.

9. The wafer inspection device according to claim 8, characterized in that: The first light source and the second light source are both bar-shaped light sources.

10. The wafer inspection device according to claim 9, characterized in that: The first light source and the second light source are the same light source, and the light emitting surfaces both cover the wafer box in the width direction of the wafer box.

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