Jig for checking and calculating defects on back surface of wafer

Abstract

The utility model provides a jig for checking and calculating wafer back defects, which is applied to the technical field of wafer defect detection and comprises a first side plate, a second side plate, a rear side plate, an INK plate and a wafer base, sliding chutes are arranged on the first side plate and the second side plate, a groove is arranged on the rear side plate, and the INK plate is arranged on the wafer base. The wafer base and the INK plate are slidably connected to the sliding groove and are in butt joint with the groove to achieve positioning. Magnetic strips are further arranged on the two sides of the INK plate and the wafer base, magnetic strips are arranged at the corresponding positions of the sliding grooves, and the INK plate and the wafer base are fixed through the magnetic strips; according to the jig, the wafer and the INK plate are fixed through the side plates with the three surrounding faces, the wafer is prevented from falling off and being damaged, and meanwhile the wafer defect is accurately judged through the equally-divided grids of the INK plate.

Description

Technical Field

[0001] The utility model relates to the technical field of wafer defect inspection, in particular to a jig for inspecting and calculating defects on the back side of a wafer. Background Art

[0002] As a high-efficiency power device, wafers are widely used in power electronic equipment. Their performance directly affects the reliability and working efficiency of the equipment. Therefore, wafer quality inspection is particularly important in the production process, among which back-side defect inspection is one of the important inspection items before shipment.

[0003] In the current wafer backside defect inspection process, major concerns include backside scratches, contamination, and color aberration, which can affect the overall performance and stability of the wafer. Traditional backside defect inspection is typically performed manually, with operators visually observing the wafer surface and manually estimating the defect ratio. However, this method has the following major drawbacks: Without a specific coordinate or grid reference, operators can only visually estimate the defect distribution on the wafer surface based on experience. This not only results in low inspection accuracy but is also prone to significant errors due to subjective judgment. It is also inconvenient and poses safety risks. During inspection, operators typically need to hold the wafer or manually position it under strong light. Due to the fragility of wafer material, the slightest mistake can cause the wafer to fall and break, further affecting product yield and cost. Due to the lack of precise reference tools, operators often spend a considerable amount of time repeatedly comparing the wafer, resulting in low efficiency, especially when inspecting large quantities of shipped wafers.

[0004] Due to the above issues, existing wafer backside defect detection methods suffer from low accuracy, inefficiency, and a high risk of wafer damage. Therefore, a dedicated fixture that can improve detection accuracy, facilitate operation, and effectively protect wafers is urgently needed to address the shortcomings of current technology and improve wafer inspection efficiency and safety. Utility Model Content

[0005] The purpose of the utility model is to provide a jig for inspecting and calculating defects on the back side of a wafer, thereby replacing the traditional method of observing defects by holding the wafer with the naked eye and providing a better basis for judging wafer defects.

[0006] The purpose of the present invention is achieved by the following technical solution: The present invention provides a jig for inspecting and calculating defects on the back side of a wafer, which includes:

[0007] a first side panel, a second side panel, and a rear side panel, wherein the first side panel and the second side panel are arranged in parallel, the first side panel and the second side panel are provided with at least one sliding groove, and the rear side panel is arranged in an area between the first side panel and the second side panel;

[0008] An INK plate, wherein an equally divided grid is provided on the INK plate, and the INK plate is placed above the wafer. The equally divided grid area is projected to cover the wafer and is used to mark the defect distribution area on the back side of the wafer;

[0009] A wafer base is placed under the INK plate and is used to place a wafer;

[0010] At least two magnetic strips, at least one magnetic strip is fixed to the INK plate and / or the wafer base, at least one magnetic strip is fixed to the slide groove, and the INK plate and / or the wafer base are fixed in position by the magnetic strips; the INK plate and / or the wafer base are slidably connected to the slide groove.

[0011] Furthermore, it also includes a bottom plate, the first side plate, the second side plate and the rear side plate are arranged on the bottom plate; the first side plate and the second side plate are each provided with a slide groove, the INK plate is slidably connected to the slide groove, and the wafer base is placed on the bottom plate.

[0012] Furthermore, the number of the magnetic strips is at least 4, each of the slide slots is provided with at least one magnetic strip, and each of the two sides of the INK plate or wafer base is provided with at least one magnetic strip.

[0013] Furthermore, the jig for inspecting and calculating defects on the back side of the wafer also includes a base plate, and the first side plate, the second side plate and the rear side plate are arranged on the base plate; the first side plate and the second side plate are each provided with a slide groove, and at least one magnetic strip is provided on each side of the INK plate, and the INK plate is slidably connected to the slide groove; the wafer base is placed on the base plate.

[0014] Preferably, the first side plate and the second side plate are each provided with a slide groove, at least one magnetic strip is provided on each side of the wafer base, and the wafer base is slidably connected to the slide groove; the INK is placed above the first side plate and the second side plate.

[0015] Preferably, the first side plate and the second side plate are each provided with at least two slide grooves, and the INK plate and the wafer base are slidably connected to the slide grooves.

[0016] Furthermore, the first side plate and the second side plate are each provided with at least three slide grooves, and the INK plate and the wafer base are slidably connected to the slide grooves.

[0017] Preferably, the number of the magnetic strips is at least 8, two magnetic strips are provided at the connection between the INK plate and the slide, and two magnetic strips are provided at the connection between the wafer base and the slide; the slide connected to the INK plate or the wafer base is provided with at least one magnetic strip.

[0018] Furthermore, the rear side plate is provided with at least one groove, and the INK plate and / or wafer base is docked in the groove.

[0019] Preferably, the wafer base is provided with a groove for placing the wafer.

[0020] Furthermore, the number of equally divided grids is 100.

[0021] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0022] First, the utility model can accurately mark and project the defect distribution area on the back of the wafer by setting equally divided grids on the INK plate, effectively improving the accuracy of back defect calculation and avoiding the errors of traditional manual visual inspection.

[0023] Second, the utility model adopts a wafer fixing structure that is surrounded on three sides, which avoids the risk of handheld wafers being damaged due to falling in traditional manual operations, and significantly improves operational safety.

[0024] Third, the slide groove and magnetic strip design of the fixture of the present invention enable the INK plate and wafer base to be reliably positioned and fixed. The automatic fixation of the magnetic strip ensures that they remain stable during operation, avoids displacement during the inspection process, and ensures the accuracy of the test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 A schematic diagram of the structure of a fixture for inspecting and calculating defects on the back side of a wafer according to the present invention;

[0027] Figure 2 A top view of a jig for inspecting and calculating defects on the back side of a wafer according to the present invention;

[0028] Figure 3 This is a rear view of the fixture used to inspect and count defects on the back side of a wafer according to the present invention.

[0029] Description of Reference Numerals

[0030] 1. First side panel; 2. Second side panel; 21. Slide slot; 3. Rear side panel; 4. Bottom panel; 5. INK panel; 6. Magnetic strip; 7. Wafer base. DETAILED DESCRIPTION

[0031] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0032] The following describes the implementation of the present invention through specific concrete examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. The present invention can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0033] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present invention, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement an apparatus and / or practice a method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this apparatus and / or practice this method.

[0034] The wafers inspected by the fixture of the present application include but are not limited to IGBT wafers; for ease of description, the wafers inspected by the fixture in the following preferred embodiments are all illustrated using IGBT wafers as an example, but it should be understood that the wafers inspected by the fixture in the present application should not be limited to IGBT wafers. All wafers that need to be inspected for back defects during production, such as single crystal silicon wafers, polycrystalline silicon wafers, compound semiconductor wafers, gallium arsenide wafers, gallium nitride wafers, silicon carbide wafers, indium phosphide wafers, silicon-on-insulator wafers, zinc sulfide wafers, sapphire wafers and graphene wafers, can use the solution of the present application. IGBT wafers should not be understood as a limitation to the wafers inspected by the fixture in the present application. Other types of wafers can also use the fixture of the present application to inspect back defects.

[0035] In the existing technology, in order to realize the defect inspection on the back side of IGBT wafers, manual visual inspection is usually used to estimate the percentage of defects in the IGBT wafer area. There is no coordinate reference and the accuracy is not high. In addition, manual inspection with an iron ring under strong light can easily cause the IGBT wafer to fall and be damaged.

[0036] Based on this, the embodiment of this specification proposes a solution for inspecting defects on the back side of an IGBT wafer: this solution only uses a fixture to fix the IGBT wafer, and then uses an INK board 5 to inspect the defect percentage on the back side of the IGBT wafer.

[0037] Example 1:

[0038] Figure 1 The figure shows a jig for inspecting and counting defects on the back side of an IGBT wafer in the present application, which is intended to improve inspection accuracy and ease of operation and avoid damage to the IGBT wafer; Figure 1 As shown, the fixture includes a first side plate 1, a second side plate 2, a rear side plate 3, a bottom plate 4, an INK plate 5, a magnetic strip 6 and a wafer base 7; the first side plate 1 and the second side plate 2 are arranged in parallel, and the first side plate 1 and the second side plate 2 are each provided with a slide groove 21, and magnetic strips 6 are provided on both sides of the INK plate 5 and at the slide groove 21 for sliding connection of the INK plate 5; the design of the slide groove 21 facilitates adjustment of the position of the INK plate 5 according to the IGBT wafer so that it is always located above the IGBT wafer; the wafer base 7 is placed on the bottom plate 4 for placing the IGBT wafer; the INK plate 5 is moved at the slide groove 21 by pushing it, and thus placed above the IGBT wafer.

[0039] In a preferred embodiment, the wafer base 7 is provided with a groove, the size of the groove matches the IGBT wafer, which can effectively fix the IGBT wafer and prevent the IGBT wafer from sliding or falling during the detection process; magnetic strips 6 are provided on both sides of the wafer base 7, and are fixed in the slide groove 21 through the magnetic strips 6; the groove can also be directly provided on the bottom plate 4, thereby replacing the wafer base 7.

[0040] In a preferred embodiment, the INK plate 5 is made of a transparent acrylic material and is provided with a grid area divided into 100 equal parts for marking and projecting the distribution of defects on the back side of the IGBT wafer; each equally divided grid represents a percentage of the area of the back side of the IGBT wafer, making it convenient for the operator to accurately calculate the defect ratio; the INK plate 5 is slidably connected to the fixture through a slide groove 21 and can be slid back and forth to ensure accurate coverage of the back side of the IGBT wafer; magnetic strips 6 are embedded on both sides of the INK plate 5 and on both sides of the slide groove 21, and the magnetic strips 6 are used to fix the position of the INK plate 5 and the wafer base 7 to ensure that the INK plate 5 does not move during the inspection process; the fixing method of the magnetic strips 6 is not only stable, but also easy to disassemble and adjust.

[0041] Example 2:

[0042] Compared with the jig of the first embodiment, the second embodiment of the present application is a jig for inspecting and calculating defects on the back side of an IGBT wafer. In this embodiment, a wafer base 7 is slidably connected to a slide groove 21, magnetic strips 6 are provided on both sides of the wafer base 7 and at the slide groove 21, and an INK plate 5 is fixed above the wafer base 7; preferably, the INK plate 5 is placed on the first side plate and the second side plate, and is fixedly connected to the first side plate and the second side plate by bolts; by pushing the wafer base 7 to move at the slide groove 21, it is placed under the INK plate 5, which facilitates observation of the IGBT wafer placed on the wafer base 7 through the INK plate 5.

[0043] Example 3:

[0044] Compared with the jigs of the first and second embodiments, the jig for inspecting and calculating defects on the back side of IGBT wafers in the third embodiment of the present application has two slide grooves 21 on each of the first side plate 1 and the second side plate 2 for sliding connection of the INK plate 5 and the wafer base 7; it should be noted that the slide groove 21 can be set only on one side of the INK plate 5 and the wafer base 7, that is, the slide groove 21 is only set on the first side plate 1 or the second side plate 2, and the magnetic strip 6 corresponding to the slide groove 21 is also only set on one side, so as to realize unilateral fixation of the INK plate 5 and the wafer base 7; by pushing the INK plate 5 and the wafer base 7 to move them at the slide groove 21, the IBGT wafer is placed under the INK plate 5, which is convenient for observing the IGBT wafer placed on the wafer base 7 through the INK plate 5, and the positions of the INK plate 5 and the wafer base 7 can be adjusted, which greatly increases the flexibility of the jig.

[0045] In a preferred embodiment, Figure 1 As shown, the rear side panel 3 is arranged perpendicular to the direction of the left and second side panels 2, serving as an additional support and positioning structure to improve the overall stability of the fixture and prevent the INK plate 5 and the wafer base 7 from escaping from the slide groove 21; a groove is provided on the rear side panel 3, and the INK plate 5 and the wafer base 7 can be slidably connected and docked into the groove to ensure the stability of the IGBT wafer inspection; preferably, the position of the rear side panel 3 should be located in the middle area between the first side panel 1 and the second side panel 2; the rear side panel 3 can be set at a position exceeding the length of the first side panel 1 and the second side panel 2, but the length exceeding the first side panel 1 and the second side panel 2 should be less than the length of the IGBT wafer to be inspected; the rear side panel 3 can also be arranged in contact with the first side panel 1 and the second side panel 2, or be integrally formed with the first side panel 1 and the second side panel 2.

[0046] The utility model has a wide range of application scenarios and is suitable for various types of IGBT wafer back side defect detection, including but not limited to back side scratches, stains, color difference, etc.; during use, the operator first places the IGBT wafer in the groove of the wafer base 7, and adjusts the INK plate 5 above the IGBT wafer so that 100 equally divided grids cover the back side of the IGBT wafer; by observing the grid area, the operator can accurately locate and mark the distribution area of defects on the back side of the IGBT wafer; according to the number of grids where the defects are located, the percentage of defects in the IGBT wafer area can be quickly calculated, thereby accurately evaluating the quality of the IGBT wafer.

[0047] In addition, under the spirit of the invention, the specific embodiment of the jig for inspecting and calculating defects on the back side of the IGBT wafer of the present invention can also add new variations on the basis of the above embodiments, such as Figure 1 As shown: three slide grooves 21 are respectively provided on the first side plate 1 and the second side plate 2, so as to adjust the vertical relative position of the INK plate 5 and the wafer base 7, so that the IGBT wafer can be inspected from a distance or near; and the other components and the connection methods between the components are the same as the embodiments described above in the present invention, and will not be repeated here due to space reasons; but it should be understood that these components and the connection methods between the components can be introduced into this variation as equivalent embodiments.

[0048] In this specification, the same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments; in particular, for the embodiments described later, the description is relatively simple, and the relevant parts can be referred to the partial description of the aforementioned embodiments.

[0049] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A jig for inspecting and counting defects on the back side of a wafer, characterized in that: include: a first side panel, a second side panel, and a rear side panel, wherein the first side panel and the second side panel are arranged in parallel, each of the first side panel and the second side panel is provided with at least one sliding groove, and the rear side panel is arranged in an area between the first side panel and the second side panel; An INK plate, wherein an equally divided grid is provided on the INK plate, and the INK plate is placed above the wafer. The equally divided grid area is projected to cover the wafer and is used to mark the defect distribution area on the back side of the wafer; A wafer base, which is placed under the INK plate and is used to place the wafer; At least two magnetic strips, at least one magnetic strip is fixed to the INK plate and / or the wafer base, at least one magnetic strip is fixed to the slide groove, and the INK plate and / or the wafer base are fixed in position by the magnetic strips; the INK plate and / or the wafer base are slidably connected to the slide groove.

2. The jig for inspecting and calculating wafer backside defects according to claim 1, characterized in that: The number of the magnetic strips is at least 4, each of the chute is provided with at least one magnetic strip, and each of the two sides of the INK plate or the wafer base is provided with at least one magnetic strip.

3. The jig for inspecting and calculating wafer backside defects according to claim 2, wherein: It also includes a bottom plate, the first side plate, the second side plate and the rear side plate are arranged on the bottom plate; the first side plate and the second side plate are each provided with a slide groove, at least one magnetic strip is provided on each side of the INK plate, and the INK plate is slidably connected to the slide groove; the wafer base is placed on the bottom plate.

4. The jig for inspecting and calculating wafer backside defects according to claim 2, wherein: The first side plate and the second side plate are each provided with a slide groove, at least one magnetic strip is provided on each side of the wafer base, and the wafer base is slidably connected to the slide groove; the INK is placed above the first side plate and the second side plate.

5. The jig for inspecting and calculating wafer backside defects according to claim 1, wherein: The first side plate and the second side plate are each provided with at least two slide grooves, and the INK plate and the wafer base are slidably connected to the slide grooves.

6. The jig for inspecting and calculating wafer backside defects according to claim 5, characterized in that: The first side plate and the second side plate are each provided with at least three slide grooves, and the INK plate and the wafer base are slidably connected to the slide grooves.

7. The jig for inspecting and calculating wafer backside defects according to claim 5 or 6, characterized in that: The number of the magnetic strips is at least 8, two magnetic strips are provided at the connection between the INK plate and the slide, and two magnetic strips are provided at the connection between the wafer base and the slide; the slide connected to the INK plate or the wafer base is provided with at least one magnetic strip.

8. The jig for inspecting and calculating wafer backside defects according to claim 7, characterized in that: The rear side plate is provided with at least one groove, and the INK plate and / or the wafer base is docked in the groove.

9. The jig for inspecting and calculating wafer backside defects according to claim 1, wherein: The wafer base is provided with a groove for placing the wafer.

10. The jig for inspecting and calculating wafer backside defects according to claim 1, wherein: The number of the equally divided grids is 100.

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