Wafer hidden crack detection device

Abstract

The utility model discloses a wafer hidden crack detection device, and the device comprises a moving assembly which comprises a heat conduction pipe, a drive unit, and at least one guide rail extending in a set direction; the hidden crack detection assembly comprises a working platform deck used for fixing a wafer, the working platform deck is installed on the guide rail and can move relative to the guide rail in the set direction under the action of the driving unit, and at least part of the working platform deck covers the heat conduction pipe; and the visual detection assembly comprises an infrared detection camera, and the infrared detection camera is used for shooting an image of the wafer heated by the heat conduction pipe. According to the device, hidden crack detection can be carried out on the heated wafer, and the detection effect on the hidden crack defect of the wafer is improved.

Description

Technical Field

[0001] This application relates to the field of wafer defect detection technology, and in particular to a wafer microcrack detection device. Background Technology

[0002] Silicon carbide (SiC) wafers, as an important semiconductor material, are widely used in electronic devices operating in extreme environments such as high power, high frequency, and high temperature. During the production and manufacturing process of SiC wafers, wafer stability plays a crucial role in their operational efficiency. However, due to the instability of upstream processes and the influence of environmental factors, microcracks can appear in SiC wafers. Microcracks not only affect the physical structure of the wafer but also have a serious negative impact on subsequent processing techniques. Particularly in wafer doping control, the inability to effectively distinguish between heavily doped and lightly doped SiC wafers further reduces wafer quality and performance. Therefore, timely detection of microcrack defects during wafer manufacturing is extremely important.

[0003] In the existing technology, infrared microcrack imaging is the main method for detecting microcrack defects, and its detection rate is relatively high. However, due to the complex distribution of microcrack defects in heavily doped silicon carbide wafers, traditional infrared microcrack detection methods cannot effectively identify microcrack defects on heavily doped silicon carbide wafers in some cases, resulting in a low detection rate of microcrack defects on heavily doped silicon carbide wafers. The detection effect of wafer microcrack defects needs to be further improved. Utility Model Content

[0004] To address the shortcomings of existing technologies, the purpose of this application is to provide a wafer microcrack detection device that can detect microcracks in heated wafers, thereby improving the detection effect of wafer microcrack defects.

[0005] To achieve the above objectives, this application adopts the following technical solution:

[0006] A wafer microcrack detection device includes: a moving component, which includes a heat pipe, a driving unit, and at least one guide rail extending along a predetermined direction; a microcrack detection component, which includes a work stage for fixing the wafer, the work stage being mounted on the guide rail and capable of moving relative to the guide rail along the predetermined direction under the action of the driving unit, with at least a portion of the work stage covering the heat pipe; and a vision inspection component, which includes an infrared detection camera for capturing images of the wafer after it has been heated by the heat pipe.

[0007] Furthermore, the extension direction of the heat pipe is parallel to the extension direction of the guide rail, enabling the heat pipe to continuously heat the wafer during the movement of the work platform.

[0008] Furthermore, the work stage includes a stage base plate, which forms a mounting area for placing wafers. The stage base plate is provided with multiple clamping mechanisms, at least a portion of which extends into the mounting area, wherein the mounting area penetrates the stage base plate.

[0009] Furthermore, the work platform also includes a platform cover and control elements for driving the clamping mechanism. The platform cover is disposed on the platform base plate, so that the control elements and / or at least part of the clamping mechanism are located within the space formed by the platform cover.

[0010] Furthermore, the clamping mechanism includes an adjusting bracket and a fixed shaft. The adjusting bracket is connected to the base plate of the platform via the fixed shaft and is capable of rotating circumferentially along the fixed shaft. The control element includes a cylinder. One end of the adjusting bracket extends into the installation area, and the other end of the adjusting bracket is connected to the cylinder.

[0011] Furthermore, the control element also includes an elastic element, which is located at the same end of the adjusting bracket as the cylinder. The elastic element is used to apply an adjusting force to the adjusting bracket, and the adjusting force is opposite to the driving force of the cylinder.

[0012] Furthermore, the guide rail includes a first guide rail extending along a first predetermined direction and a second guide rail extending along a second predetermined direction. The first predetermined direction and the second predetermined direction are both parallel to the horizontal plane and perpendicular to each other. The second guide rail is mounted on the first guide rail and can slide relative to the first guide rail along the first predetermined direction. The work platform is mounted on the second guide rail and can slide relative to the second guide rail along the second predetermined direction.

[0013] Furthermore, the guide rail includes a pair of second guide rails extending along a second predetermined direction, and the pair of second guide rails are distributed along a first predetermined direction on two opposite sides of the worktable.

[0014] Furthermore, the heat pipe is arranged between a pair of second guide rails, and the two ends of the heat pipe are respectively connected to the second guide rails in the corresponding directions.

[0015] Furthermore, the wafer microcrack detection device also includes a base plate, a moving component mounted on the base plate, a vision inspection component mounted on the base plate, and an infrared inspection camera suspended above the guide rail.

[0016] The wafer microcrack detection device provided in this application heats the wafer on the work platform through a heat pipe, so that the microcrack defect can be more clearly displayed under the action of thermal stress. Compared with the prior art, the vision inspection component can capture clearer and higher contrast microcrack images when inspecting the heated wafer, thereby significantly improving the detection effect of wafer microcrack defects. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the wafer microcrack detection device in the embodiments of this application;

[0018] Figure 2 This is a schematic diagram of the wafer microcrack detection device from another angle in the embodiments of this application;

[0019] Figure 3 This is a schematic diagram of the structure of the microcrack detection component in the embodiments of this application;

[0020] Figure 4 This is a schematic diagram of the structure of the platform base plate in the embodiment of this application.

[0021] Reference numerals: 100, wafer microcrack detection device; 10, base plate; 20, moving component; 21, heat pipe; 22, drive unit; 23, guide rail; 231, first guide rail; 232, second guide rail; 30, microcrack detection component; 31, work platform; 311, platform base plate; 3111, mounting area; 312, platform cover; 313, control element; 3131, cylinder; 3132, elastic element; 3133, limit block; 314, clamping mechanism; 3141, adjusting bracket; 3142, fixed shaft; 40, vision inspection component; 41, infrared inspection camera; 42, support frame. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present application, the technical solutions in specific embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0023] It should be noted that the directional terms such as up, down, left, right, front, and back, or ordinal numbers such as "first," "second," "third," and "fourth" mentioned in this document are introduced for ease of description based on the accompanying drawings and do not imply any limitation on the order of the components. Furthermore, since some parts of the components provided in the above embodiments have the same function, this specification uses a unified naming convention for these parts. The above provides a detailed description of the pipe connection device provided by the relevant technical solution. Specific embodiments have been used in this document for illustration. The descriptions of the above embodiments are only for helping to understand the method and core ideas of the present invention and are not intended to limit the present invention in any way.

[0024] like Figure 1 As shown, this application provides a wafer microcrack detection device 100. The wafer microcrack detection device 100 includes a base plate 10, a moving component 20, a microcrack detection component 30, and a vision inspection component 40. The base plate 10 is the basic support part of the entire device. The moving component 20 and the vision inspection component 40 are mounted on the base plate 10. The microcrack detection component 30 is indirectly mounted on the base plate 10 through the moving component 20. The base plate 10 provides stable support for the entire device, ensuring that each component maintains a precise relative position during operation.

[0025] The moving assembly 20 includes a heat pipe 21, a drive unit 22, and at least one guide rail 23 extending along a predetermined direction. The guide rail 23 is fixed to the base plate 10, and at least a portion of the heat pipe 21 is fixed to the guide rail 23. The heat pipe 21 is responsible for heating the wafer to generate the necessary thermal stress, allowing microcracks to appear during heat treatment. The drive unit 22 is the power source for the entire assembly. By controlling the movement of the work stage 31 along the guide rail 23, it achieves precise positioning of the wafer and coverage of the heating area, thereby ensuring the uniformity of the heating process. The guide rail 23 serves as a basic support structure, ensuring that the work stage 31 can move smoothly and accurately along the predetermined direction. The guide rail 23 provides a fixed path, ensuring that the work stage 31 does not deviate from the predetermined trajectory during movement, thereby maintaining the stability of the wafer's position and preventing unnecessary displacement of the wafer during heating and inspection.

[0026] In some examples, if the guide rail 23 can move relative to the base plate 10, the heat pipe 21 can move under the influence of the guide rail 23.

[0027] The microcrack detection assembly 30 includes a work stage 31 for fixing the wafer. The work stage 31 is mounted on a guide rail 23 and can move relative to the guide rail 23 in a set direction under the action of the drive unit 22. The guide rail 23 provides guidance for the work stage 31. At least a portion of the work stage 31 covers a heat pipe 21, which is located below the work stage 31. The function of the work stage 31 is to fix the wafer, ensuring that the wafer maintains a stable position during detection and heating. The fact that the work stage 31 at least partially covers the heat pipe 21 ensures that the heat pipe 21 is always covered by the bottom of the wafer during heating, providing a stable heat source.

[0028] The visual inspection assembly 40 includes an infrared inspection camera 41, which is mounted on the base plate 10, suspended above and parallel to the guide rail 23. The infrared inspection camera 41 is used to capture images of the wafer after it has been heated by the heat pipe 21. The visual inspection assembly 40 uses the infrared inspection camera 41 to image the heated wafer, capturing areas of microcracks that are more easily visible due to the increased wafer temperature, and accurately detects the presence of microcracks in the wafer through image analysis.

[0029] In this embodiment, the wafer is placed in the work stage 31, and the heat pipe 21 of the work stage 31 starts working. As the work stage 31 moves along the guide rail 23, the heat pipe 21 maintains uniform heating of the wafer, causing thermal stress on the wafer. Microcrack defects become apparent as the wafer's temperature changes. The vision inspection component 40 acquires images of the heated wafer and identifies microcrack defects that have appeared due to the temperature rise. Throughout the process, the work stage 31 slides smoothly along the guide rail 23, ensuring that the wafer can be heated and accurately inspected whenever the work stage 31 moves to any position. As the work stage 31 continues to move, the device can perform continuous microcrack inspection.

[0030] With the above settings, the wafer can be stably heated on the work stage 31, and the hidden crack defects revealed by the heating can be accurately detected by the infrared detection camera 41. This enables the effective revelation of hidden crack defects in heavily doped silicon carbide wafers, significantly improving the detection rate of hidden cracks in heavily doped silicon carbide wafers and ensuring higher detection reliability.

[0031] like Figure 1 As shown, in one implementation, the extension direction of the heat pipe 21 is parallel to the extension direction of the guide rail 23, so that the heat pipe 21 can continuously heat the wafer during the movement of the work stage 31.

[0032] For example, the heat pipe 21 is disposed between a pair of guide rails 23, and the heat pipe 21 always maintains a stable position, thereby effectively heating the wafer and ensuring that the heat pipe 21 can stably heat the wafer during the sliding of the work stage 31. The movement of the work stage 31 will not cause the position of the heat pipe 21 to shift, ensuring the continuity and uniformity of the heating process.

[0033] The above settings ensure the relative positional relationship between the heat pipe 21 and the work stage 31, so that the wafer can be continuously heated by the heat pipe 21 throughout the entire movement process, avoiding interruptions, thereby ensuring more uniform heating of the wafer and improving the accuracy of microcrack detection.

[0034] like Figure 2 As shown, in one implementation, the guide rail 23 includes a first guide rail 231 extending along a first predetermined direction and a second guide rail 232 extending along a second predetermined direction. The first predetermined direction and the second predetermined direction are both parallel to the horizontal plane and perpendicular to each other. The second guide rail 232 is mounted on the first guide rail 231 and can slide relative to the first guide rail 231 along the first predetermined direction. The work platform 31 is mounted on the second guide rail 232 and can slide relative to the second guide rail 232 along the second predetermined direction.

[0035] Specifically, since the first guide rail 231 and the second guide rail 232 are perpendicular to each other and extend along two set directions on the horizontal plane respectively, the work stage 31 can slide along the two set directions. The movement of the work stage 31 along each set direction is independently controlled and is not affected by the other set direction. This allows for precise alignment with the target area for heating and detection, enabling the heat pipe 21 to heat different areas on the wafer. This ensures that the image acquired by the infrared detection camera 41 comes from the wafer after all areas have been heated, thereby obtaining more accurate microcrack detection results.

[0036] Furthermore, the guide rail 23 includes a pair of second guide rails 232 extending along a second predetermined direction, and the pair of second guide rails 232 are distributed on two opposite sides of the work platform 31 along a first predetermined direction. The pair of second guide rails 232 provide a track for the work platform 31 to slide smoothly along the second predetermined direction.

[0037] like Figure 2 As shown, in one implementation, the heat pipe 21 is arranged between a pair of second guide rails 232, and the two ends of the heat pipe 21 are respectively connected to the second guide rails 232 in the corresponding directions.

[0038] Furthermore, multiple heat pipes 21 are disposed between a pair of second guide rails 232, with the heat pipes 21 spaced apart. This spacing between the heat pipes 21 allows the wafer to receive heat evenly, avoiding localized overheating or underheating. Uniform heating helps to reveal microcracks and ensures that the image captured by the infrared camera accurately reflects the true condition of the heated area, thereby improving the accuracy of microcrack detection. Through the above arrangement, any microcracks that may exist on the wafer can be fully revealed during the heating process, facilitating subsequent inspection.

[0039] like Figure 1 and Figure 2 As shown, in one implementation, the moving component 20 is mounted on the base plate 10, and the visual inspection component 40 is mounted on the base plate 10, so that the infrared inspection camera 41 is suspended above the guide rail 23.

[0040] For example, the visual inspection component 40 includes a support frame 42, which is configured as an H-shaped structure. One end of the support frame 42 is fixed to the base plate 10. The support frame 42 is mounted above the guide rail 23. The projection of the support frame 42 on the base plate 10 is perpendicular to the first guide rail 23. An infrared detection camera 41 is provided on the side of the crossbeam facing the work platform 31. The movement range of the work platform 31 is always kept within the detection range of the infrared detection camera 41.

[0041] With the above settings, the position and shooting angle of the infrared inspection camera 41 are not affected when the work stage 31 slides along the guide rail 23. The infrared inspection camera 41 always remains aligned with the wafer for inspection, and can stably capture images of the heated wafer, avoiding image deviations or interference caused by the movement of the work stage 31. This ensures the stability of the captured images, thereby improving the accuracy of microcrack detection and further increasing the identification rate of microcrack defects.

[0042] like Figure 3 As shown, in one implementation, the work stage 31 includes a stage base plate 311, which forms a mounting area 3111 for placing the wafer. This mounting area 3111 is used to match the size and shape of the wafer, and it extends through the stage base plate 311. This design prevents wafer fragments from falling into the mounting area 3111 and affecting the detection results of microcracks in the wafer.

[0043] The outer contour of the installation area 3111 is basically U-shaped.

[0044] The stage base plate 311 is provided with multiple clamping mechanisms 314. At least a portion of the clamping mechanism 314 extends into the mounting area 3111 and contacts the wafer to fix the wafer located in the mounting area 3111. The clamping mechanism 314 can firmly fix the wafer in the mounting area 3111. When the work stage 31 moves, the wafer can also remain stable and will not be affected by external disturbances, ensuring the accurate and stable position of the wafer during the microcrack detection process.

[0045] like Figure 3 and Figure 4 As shown, specifically, the work stage 31 also includes a stage cover 312 and a control element 313 for driving the clamping mechanism 314. The stage cover 312 covers the stage base plate 311, so that the control element 313 and / or at least part of the clamping mechanism 314 are located within the space formed by the stage cover 312. The stage cover 312 serves a protective and enclosed function. Through the enclosed design of the stage cover 312, the control element 313 and the clamping mechanism 314 can be protected from external environmental interference, such as dust and temperature changes, thereby improving the reliability and stability of the device. The control element 313 is used to precisely control the movement of the clamping mechanism 314, enabling it to adjust the clamping force as needed, thereby firmly fixing the wafer in the work stage 31 and ensuring the stability of the wafer during the inspection process.

[0046] In this embodiment, the clamping mechanism 314 includes an adjusting bracket 3141 and a fixed shaft 3142. The adjusting bracket 3141 is connected to the stage base plate 311 via the fixed shaft 3143 and can rotate circumferentially along the fixed shaft 3143. The control element 313 includes a cylinder 3131. One end of the adjusting bracket 3141 extends into the mounting area 3111 for contacting the wafer, and the other end of the adjusting bracket 3141 is connected to the cylinder 3131.

[0047] Furthermore, the control element 313 also includes an elastic element 3132, which is disposed at the same end of the adjusting bracket 3141 as the cylinder 3131. The elastic element 3132 is used to apply an adjusting force to the adjusting bracket 3141, and the adjusting force is opposite to the driving force of the cylinder 3131.

[0048] The cylinder 3131 and the elastic element 3132 are located at the same end and on the same side of the adjusting bracket 3141. When the cylinder 3131 drives the adjusting bracket 3141 to rotate, the elastic element 3132 extends and applies an adjusting force to the adjusting bracket 3141 opposite to the driving force of the cylinder 3131, thereby fine-tuning the rotation angle of the adjusting bracket 3141.

[0049] Optionally, the cylinder 3131 and the elastic element 3132 are disposed at the same end of the adjusting bracket 3141 and located on different sides of the adjusting bracket 3141. When the cylinder 3131 drives the adjusting bracket 3141 to rotate, the elastic element 3132 is compressed and applies an adjusting force to the adjusting bracket 3141 opposite to the driving force of the cylinder 3131, thereby finely adjusting the rotation angle of the adjusting bracket 3141.

[0050] More specifically, the control element 313 also includes a limiting block 3133, which is fixed to the stage base plate 311. The limiting block 3133 and the cylinder 3111 are located on the same side of the adjusting bracket 3141. When the cylinder 3111 drives the adjusting bracket 3141 to reset, the adjusting bracket 3141 abuts against the limiting block 3133, preventing the end of the adjusting bracket 3141 that is in contact with the wafer from colliding with the wafer under the elastic force of the elastic element 3132.

[0051] As one implementation, the wafer microcrack detection device 100 also includes a signal processing module, which is used to receive detection commands sent by the host computer and control the motor, infrared detection camera 41 and / or heat pipe 21 in response to the detection commands.

[0052] For example, when the work stage 31 needs to be precisely positioned, the signal processing module adjusts the position of the work stage 31 by precisely controlling the drive unit 22, and adjusts the imaging parameters of the infrared detection camera 41 or the heating temperature of the heat pipe 21 according to the need for accurate image acquisition.

[0053] The addition of a signal processing module makes the operation of the wafer microcrack detection device 100 more automated. By responding to the detection commands from the host computer, the signal processing module can effectively control the working status of each component. Through the coordinated control of multiple components (such as the drive unit 22, the infrared detection camera 41, and the heat pipe 21), the signal processing module ensures the consistency and synchronization of the heating process, the image acquisition process, and the detection process, avoiding microcrack detection errors caused by uneven heating or image misalignment, and enhancing the reliability of microcrack detection results.

[0054] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A wafer microcrack detection device, characterized in that, include: The moving component (20) includes a heat pipe (21), a drive unit (22) and at least one guide rail (23) extending in a set direction; The microcrack detection assembly (30) includes a work stage (31) for fixing the wafer, the work stage (31) is mounted on the guide rail (23) and can move relative to the guide rail (23) in the set direction under the action of the drive unit (22), and at least part of the work stage (31) covers the heat pipe (21). A visual inspection component (40) includes an infrared inspection camera (41) for capturing images of the wafer after it has been heated by the heat pipe (21).

2. The wafer microcrack detection device according to claim 1, characterized in that, The extension direction of the heat pipe (21) is parallel to the extension direction of the guide rail (23), so that the heat pipe (21) can continuously heat the wafer during the movement of the work stage (31).

3. The wafer microcrack detection device according to claim 1, characterized in that, The work stage (31) includes a stage base plate (311), which forms a mounting area (3111) for placing wafers. A plurality of clamping mechanisms (314) are provided on the stage base plate (311), at least a portion of which extends into the mounting area (3111), wherein the mounting area (3111) penetrates the stage base plate (311).

4. The wafer microcrack detection device according to claim 3, characterized in that, The work platform (31) also includes a platform cover (312) and a control element (313) for driving the clamping mechanism (314). The platform cover (312) covers the platform base plate (311) so that the control element (313) and / or at least part of the clamping mechanism (314) are located within the space formed by the platform cover (312).

5. The wafer microcrack detection device according to claim 4, characterized in that, The clamping mechanism (314) includes an adjusting bracket (3141) and a fixed shaft (3143). The adjusting bracket (3141) is connected to the base plate (311) of the platform via the fixed shaft (3143) and is rotatable around the fixed shaft (3143). The control element (313) includes a cylinder (3131). One end of the adjusting bracket (3141) extends into the mounting area (3111), and the other end of the adjusting bracket (3141) is connected to the cylinder (3131).

6. The wafer microcrack detection device according to claim 5, characterized in that, The control element (313) further includes an elastic element (3132), which is disposed at the same end of the adjusting bracket (3141) as the cylinder (3131). The elastic element (3132) is used to apply an adjusting force to the adjusting bracket (3141), and the adjusting force is opposite to the driving force of the cylinder (3131).

7. The wafer microcrack detection device according to claim 1, characterized in that, The guide rail (23) includes a first guide rail (231) extending along a first set direction and a second guide rail (232) extending along a second set direction. The first set direction and the second set direction are both parallel to the horizontal plane and perpendicular to each other. The second guide rail (232) is mounted on the first guide rail (231) and can slide relative to the first guide rail (231) along the first set direction. The work platform (31) is mounted on the second guide rail (232) and can slide relative to the second guide rail (232) along the second set direction.

8. The wafer microcrack detection device according to claim 7, characterized in that, The guide rail (23) includes a pair of second guide rails (232) extending along the second set direction, and the pair of second guide rails (232) are distributed along the first set direction on two opposite sides of the work platform (31).

9. The wafer microcrack detection device according to claim 8, characterized in that, The heat pipe (21) is arranged between a pair of second guide rails (232), and the two ends of the heat pipe (21) are respectively connected to the second guide rails (232) in the corresponding directions.

10. The wafer microcrack detection device according to claim 1, characterized in that, The wafer microcrack detection device (100) also includes a base plate (10), the moving component (20) is mounted on the base plate (10), and the visual inspection component (40) is mounted on the base plate (10), so that the infrared inspection camera (41) is suspended above the guide rail (23).

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