A wafer defect detection device and detection method

Abstract

This invention discloses a wafer defect detection device and method, belonging to the field of wafer inspection technology. Addressing the problems of low efficiency and incomplete detection of surface and dicing quality after blue film coating on wafers in existing technologies, this invention provides a wafer defect detection device and method. Several calibration plates are equidistantly arranged on a calibration ring. The calibration ring is connected to a diffuser plate. The calibration plates, calibration ring, and diffuser plate constitute a calibration device. A circuit board is fixedly mounted on a second light source component. The circuit board and the second light source component constitute a backlight device. One end of a first light source component is connected to the calibration device, and the other end of the first light source component is connected to the backlight device. The calibration device, the first light source component, and the backlight device constitute the wafer defect detection device. By fixing the calibration plates on the calibration ring, the repeated calibration of the camera-wafer positional relationship is avoided, thereby saving inspection time and effectively improving inspection efficiency.

Description

Technical Field

[0001] This invention relates to the field of wafer inspection technology, and more specifically, to a wafer defect detection device and method. Background Technology

[0002] Currently, the common manufacturing process for blue film chips involves applying a blue film to GPP (Glass Passivated Polymer) chips and then cutting them completely into loose particles using a blade. GPP wafer products refer to chips manufactured in a processing plant, meaning chips that have been etched but not yet packaged. These chips only have solder joints for packaging and cannot be directly used in actual circuits. Furthermore, these wafer chips are highly susceptible to external environmental temperatures and physical forces. Therefore, they need to be packaged inside a protective enclosure, and then led out to the corresponding solder joints via wires, thus serving as a basic electronic component. Because wafers are easily damaged by external environmental influences at various stages of production, surface visual inspection of wafer products is necessary during manufacturing. GPP blue film products refer to products with a blue film coating, typically blue, hence the name. The purpose of wafer coating is to prevent the individual chips from scattering after dicing. Therefore, the wafer needs to be coated with a blue film to ensure the position of each chip is easily handled in the next process. Since the GPP blue film products are used directly for packaging after cutting, it is necessary to inspect the surface quality and cutting quality of the GPP blue film products again. The inspection includes whether there are defects such as chipped edges and off-cut edges.

[0003] In existing technologies, using a machine vision inspection system is the most efficient and fastest way to inspect GPP blue film products. In actual production, the surface quality and cutting quality of GPP blue film products are mainly inspected using a camera. Generally, a calibration board is placed under the camera for calibration, and after calibration, it is removed before inspecting the wafer-coated product. Since moving the camera requires repositioning the calibration board under the camera for repeated calibration, it is time-consuming and labor-intensive. Furthermore, the camera's field of view cannot show the entire wafer-coated product at once; multiple photos are needed to ensure the entire wafer is captured, limiting the inspection capabilities of wafer-coated products. In addition, existing film expansion mechanisms (backlight lifting the blue film solution) easily create a sealed space between the upper surface of the light source and the blue film, preventing air from escaping in time and causing a bulge in the center of the blue film, affecting image quality. Therefore, a wafer defect detection device needs to be designed that avoids repeatedly calibrating the camera-wafer position and can promptly remove air generated between the blue film and the upper surface of the light source, ensuring image quality. Summary of the Invention

[0004] 1. Technical problems to be solved

[0005] To address the problems in existing technologies, such as cumbersome and inefficient steps for inspecting the surface and dicing quality of wafers after blue film coating via camera, incomplete inspection, and the tendency for a sealed space to form between the upper surface of the light source and the blue film in existing film expansion mechanisms, which prevents timely air expulsion and causes the center of the blue film to bulge, affecting image quality, this invention provides a wafer defect detection device and method. By fixing a calibration plate to a calibration ring, the device avoids repeatedly calibrating the positional relationship between the camera and the wafer, effectively saving inspection time. Furthermore, several vent holes are provided on the detection device to promptly expel air between the blue film and the upper surface of the light source, ensuring image quality.

[0006] 2. Technical Solution

[0007] The objective of this invention is achieved through the following technical solutions.

[0008] A wafer defect detection device includes a calibration plate, a calibration ring, a diffuser plate, a first light source component, a circuit board, and a second light source component. A plurality of calibration plates are equidistantly distributed on the calibration ring, and the calibration ring is connected to the diffuser plate. The calibration plates, calibration ring, and diffuser plate constitute a calibration device. The circuit board is fixedly mounted on the second light source component, and the circuit board and second light source component constitute a backlight device. One end of the first light source component is connected to the calibration device, and the other end of the first light source component is connected to the backlight device. The calibration device, first light source component, and backlight device constitute the detection device. The circuit board, first light source component, diffuser plate, and calibration ring are arranged sequentially along the light source direction.

[0009] Furthermore, the calibration plate is provided with closed loop markings.

[0010] Furthermore, the detection device has several exhaust holes arranged at equal intervals.

[0011] Furthermore, the circuit board is provided with a number of regularly distributed surface-mount LEDs.

[0012] Furthermore, the diffuser angle of the patch LED is 90° to 150°.

[0013] Furthermore, the detection device also includes a light source connector, which is connected to the circuit board.

[0014] A detection method based on a wafer defect detection device includes the following steps:

[0015] After the wafer is cut into several grains, it is coated with a blue film and then placed on the detection device.

[0016] The calibration board calibrates the positional relationship between the camera and the wafer;

[0017] Stretching the blue film increases the kerf between grains on the wafer;

[0018] The light source connector connects to the power supply, and the light source emitted by the circuit board passes through the slits in the wafer;

[0019] The camera and wafer are moved in parallel, and the camera is used to photograph the wafer surface to detect whether there are defects on the wafer surface.

[0020] Furthermore, the calibration plate is used to ensure that the camera is always positioned directly above the wafer to be photographed during shooting.

[0021] Furthermore, after the blue film is stretched, it expands, and the vent hole is used to remove air between the blue film and the detection device.

[0022] Furthermore, the diffuser is used to uniformly guide the light source emitted by the circuit board through the slits in the wafer.

[0023] 3. Beneficial effects

[0024] Compared with the prior art, the advantages of this invention are:

[0025] The present invention discloses a wafer defect detection device and method. By equidistantly arranging several calibration plates on a calibration ring, it is not necessary to repeatedly pick up and put down the calibration plates to calibrate the positional relationship between the camera and the wafer after moving the camera. This ensures that the movement direction of the wafer is parallel to the camera, effectively saving wafer defect detection time and greatly improving wafer defect detection efficiency. In addition, several vent holes are provided in the detection device to promptly remove air between the blue film and the upper surface of the light source, ensuring image quality and also effectively improving wafer defect detection efficiency. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention;

[0027] Figure 2 This is a three-dimensional exploded view of an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the calibration plate and calibration ring fixing structure according to an embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of the exhaust port structure according to an embodiment of the present invention;

[0030] Figure 5 This is a schematic diagram of the circuit board structure according to an embodiment of the present invention;

[0031] Figure 6 This is a top view of the blue film structure on the wafer in an embodiment of the present invention.

[0032] Figure 7 This is a front view of the blue film structure on a wafer, as described in an embodiment of the present invention.

[0033] Figure 8 This is an image showing the result of taking a picture where the moving direction of the wafer blue film structure is parallel to the moving direction of the camera, according to an embodiment of the present invention.

[0034] Figure 9 This is an image showing the result of a wafer blue film structure moving in a direction that is not parallel to the camera's moving direction, according to an embodiment of the present invention.

[0035] The labels in the diagram are as follows: 1. Calibration plate; 2. Calibration ring; 3. Diffuser plate; 4. First light source component; 5. Circuit board; 6. Second light source component; 7. Light source connector; 8. Exhaust hole; 9. Wafer; 10. Blue film. Detailed Implementation

[0036] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0037] Example

[0038] like Figure 1 The image shows a wafer defect detection device provided in this embodiment. The detection device includes a calibration plate 1, a calibration ring 2, a diffuser plate 3, a first light source component 4, a circuit board 5, and a second light source component 6. A plurality of calibration plates 1 are equidistantly distributed on the calibration ring 2. The calibration ring 2 is connected to the diffuser plate 3, and the calibration plate 1, calibration ring 2, and diffuser plate 3 constitute a calibration device. The circuit board 5 is fixedly mounted on the second light source component 6, and the circuit board 5 and second light source component 6 constitute a backlight device. One end of the first light source component 4 is connected to the calibration device, and the other end of the first light source component 4 is connected to the backlight device. The calibration device, first light source component 4, and backlight device constitute the detection device. Furthermore, along the light source direction, the components are arranged in sequence: circuit board 5, first light source component 4, diffuser plate 3, and calibration ring 2.

[0039] Specifically, in this embodiment, such as Figure 2 As shown, the testing device includes a calibration plate 1, a calibration ring 2, a diffuser plate 3, a first light source component 4, a circuit board 5, a second light source component 6, and a light source connector 7. Figure 3As shown, several calibration plates 1 are evenly distributed on the calibration ring 2. In the prior art, the size of wafer 9 is 5 inches, 6 inches, 8 inches, and 12 inches, etc. After wafer 9 is cut into several dies, the field of view of ordinary cameras cannot capture the entire die of wafer 9 in one shot. Multiple shots are required to ensure that the entire die of wafer 9 is captured. Before camera detection, the positional relationship between wafer 9 and camera needs to be calibrated. This requires that there is no angle between the movement direction of wafer 9 and the movement direction of camera, that is, the movement direction of wafer 9 must be parallel to the movement direction of camera, so as to avoid only capturing incomplete die of wafer 9 after several camera movements. Therefore, in this embodiment, by setting several calibration plates 1, there is no angle between the movement direction of wafer 9 and the movement direction of camera, ensuring that the movement direction of wafer 9 is parallel to the movement direction of camera, and the entire die of wafer 9 can be captured in one shot. It is worth noting that in this embodiment, several calibration plates 1 are equidistantly distributed on the calibration ring 2. The calibration plates 1 calibrate the positional relationship between the wafer 9 and the camera, that is, the calibration plates 1 are used to ensure that the camera is always directly above the wafer 9 to be photographed during shooting. Therefore, if the position of the camera is moved during the inspection process, it is not necessary to recalibrate the positional relationship between the wafer 9 and the camera, thereby quickly determining the positional relationship between the wafer 9 and the camera, effectively saving wafer 9 defect inspection time, and greatly improving wafer 9 defect inspection efficiency. In this embodiment, preferably, four calibration plates 1 are equidistantly distributed on the calibration ring 2. The calibration plates 1 are provided with closed loop-shaped marks. In this embodiment, the calibration plates 1 are provided with circular ring-shaped marks. Furthermore, the four equidistantly distributed calibration plates 1 are connected with the center of the circular ring-shaped marks distributed on them as the origin to form an X / Y rectangular coordinate system, thereby the wafer 9 moves along the X / Y rectangular coordinate system. The calibration ring 2 is connected to the diffuser plate 3, and the calibration plate 1, calibration ring 2, and diffuser plate 3 constitute a calibration device. Further, the circuit board 5 is fixedly mounted on the second light source component 6. In this embodiment, preferably, the circuit board 5 is an aluminum-based circuit board. It should be noted that, as... Figure 5As shown, the circuit board 5 has several regularly distributed surface-mount LEDs, with a diffuser angle of 90° to 150°. It should be noted that the larger the diffuser angle of the surface-mount LEDs, the more overlapping areas there are between the light-emitting surfaces of each LED, resulting in a more uniform backlight surface. Furthermore, the optimal arrangement of surface-mount LEDs at different angles needs to be determined through software simulation. Preferably, in this embodiment, the diffuser angle of the surface-mount LEDs is 120°. The second light source component 6 is used to fix the circuit board 5 and also serves to dissipate heat from the circuit board 5. Thus, the circuit board 5 and the second light source component 6 constitute a backlight device. The light source connector 7 is connected to the circuit board 5. The light source connector 7 is used to supply power to the circuit board 5. One end of the first light source component 4 is connected to the calibration device, and the other end of the first light source component 4 is connected to the backlight device. The calibration device, the first light source component 4, and the backlight device constitute the detection device. In this embodiment, along the light source direction, the components are, in sequence, the circuit board 5, the first light source component 4, the diffuser plate 3, and the calibration ring 2.

[0040] It is worth noting that, because a sealed space easily forms between the upper surface of the existing expanded film structure light source and the blue film 10, air cannot be expelled in time, causing a bulge in the center of the blue film 10, which affects the image quality. Therefore, if... Figure 4 As shown, in this embodiment, a plurality of vent holes 8 are equidistantly arranged on the detection device. The vent holes 8 can promptly expel the air between the blue film 10 and the upper surface of the light source, thereby ensuring the image capture effect. In the prior art, the blue film 10 is elastic; the protruding blue film 10 compresses the air in the sealed space, and the vent holes 8 can quickly expel the air. In this embodiment, considering the exhaust speed and structural strength of the detection device, preferably, four vent holes 8 are equidistantly arranged on the detection device.

[0041] like Figures 6-7As shown, this embodiment also provides a detection method based on the wafer defect detection device described above. The steps include: attaching a blue film 10 to a wafer 9 cut into several dies; placing the wafer 9 with the blue film 10 attached onto the detection device. It should be noted that attaching the wafer 9 to the blue film 10 is prior art. Further, a calibration plate 1 calibrates the positional relationship between the wafer 9 and the camera, i.e., the calibration plate 1 is used to ensure that the camera is always directly above the wafer 9 to be photographed during shooting, thereby ensuring that the movement direction of the wafer 9 is always parallel to the movement direction of the camera; stretching the blue film 10 increases the kerf of the wafer 9. It should be noted that since the kerf after wafer 9 is cut is very small, it is difficult for the backlight device to transmit light through the kerf. Therefore, the blue film 10 needs to be stretched outwards to enlarge the kerf of the wafer 9, allowing the light source to pass through. The blue film 10 is elastic. Therefore, after stretching the blue film 10, the blue film 10 expands, and the vent 8 is used to remove the air between the blue film 10 and the detection device; the light source connector 7 is connected to the power supply, and the light source emitted by the circuit board 5 passes through the slit of the wafer 9. Since the circuit board 5 is provided with several regularly distributed surface-mount LEDs, the brightness of the backlight device can be made as uniform as possible. At the same time, the diffuser 3 makes the light source emitted by the circuit board 5 pass evenly through the slit of the wafer 9; the camera and the wafer 9 are moved in parallel, and the camera is used to photograph the surface of the wafer 9 to detect whether there are defects on the surface of the wafer 9.

[0042] Furthermore, the wafer defect detection device and method described in this embodiment calibrates the positional relationship between the wafer 9 and the camera using a calibration plate 1, ensuring that the movement direction of the wafer 9 is parallel to the movement direction of the camera. Figure 8 As shown, the camera photographs wafer 9. The first photograph, area A, contains several complete wafer 9 dies. After multiple photographs, area B still contains several complete wafer 9 dies. However, the relationship between the moving direction of wafer 9 and the camera's position was not calibrated using calibration plate 1, or the calibration plate 1 was not placed first to calibrate the relationship between wafer 9 and the camera. If the camera position is moved during the inspection process, the relationship between wafer 9 and the camera needs to be repeatedly calibrated using calibration plate 1, ensuring that the moving direction of wafer 9 is not parallel to the moving direction of the camera. Figure 9 As shown, the camera takes pictures of wafer 9. The first shooting area A' contains several complete wafer 9 grains, while the shooting area B' after multiple shots contains several incomplete wafer 9 grains.

[0043] Therefore, the wafer defect detection device and method provided in this embodiment, by equidistantly arranging several calibration plates 1 on the calibration ring 2, eliminates the need for repeated calibration of the positional relationship between the camera and the wafer 9 after moving the camera, ensuring that the moving direction of the wafer 9 is parallel to the moving direction of the camera. This effectively saves wafer defect detection time and greatly improves wafer defect detection efficiency. In addition, several vent holes 8 are provided in the detection device to promptly remove air between the blue film 10 and the upper surface of the light source, ensuring image quality and also effectively improving wafer defect detection efficiency.

[0044] The invention and its embodiments have been described above illustratively. This description is not restrictive, and the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. The accompanying drawings are only one embodiment of the invention, and the actual structure is not limited thereto. No reference numerals in the claims should limit the scope of the claims. Therefore, if a person skilled in the art is inspired by this description and designs a similar structure and embodiment without departing from the spirit of the invention, such design should fall within the scope of protection of this patent. Furthermore, the word "comprising" does not exclude other elements or steps, and the word "a" preceding an element does not exclude the inclusion of "a plurality" of that element. Multiple elements stated in the product claims may also be implemented by a single element through software or hardware. The terms "first," "second," etc., are used to indicate names and do not indicate any specific order.

Claims

1. A wafer defect detection device, characterized in that, The detection device includes a calibration plate (1), a calibration ring (2), a diffuser plate (3), a first light source component (4), a circuit board (5), and a second light source component (6); several calibration plates (1) are equidistantly distributed on the calibration ring (2), and the calibration ring (2) is connected to the diffuser plate (3). The calibration plate (1), the calibration ring (2), and the diffuser plate (3) constitute a calibration device; the circuit board (5) is fixedly mounted on the second light source component (6), and the circuit board (5) and the second light source component (6) constitute a backlight device; one end of the first light source component (4) is connected to The calibration device, the other end of the first light source component (4) is connected to the backlight device, the calibration device, the first light source component (4) and the backlight device constitute the detection device; along the light source direction are the circuit board (5), the first light source component (4), the diffuser plate (3) and the calibration ring (2), the calibration plate (1) is provided with a closed ring mark, the detection device is provided with several exhaust holes (8) at equal intervals, the calibration plates (1) are distributed at equal intervals with the center of the ring mark distributed on them as the origin, and the four calibration plates (1) are connected at equal intervals to form a rectangular coordinate system.

2. The wafer defect detection device according to claim 1, characterized in that, The circuit board (5) has a number of regularly distributed surface-mount LEDs.

3. The wafer defect detection device according to claim 2, characterized in that, The diffuser angle of the surface-mount LED is 90°~150°.

4. The wafer defect detection device according to claim 1, characterized in that, The detection device also includes a light source connector (7), which is connected to the circuit board (5).

5. A detection method based on the wafer defect detection apparatus according to any one of claims 1-4, comprising the following steps: The wafer (9) cut into several grains is attached to the blue film (10), and the wafer (9) with the blue film (10) attached is placed on the detection device; The calibration board (1) calibrates the positional relationship between the camera and the wafer (9); Stretching the blue film (10) increases the kerf between the grains on the wafer (9); The light source connector (7) is connected to the power supply, and the light source emitted by the circuit board (5) passes through the slit of the wafer (9); The camera and wafer (9) are moved in parallel, and the camera is used to photograph the surface of the wafer (9) to detect whether there are defects on the surface of the wafer (9).

6. The detection method according to claim 5, characterized in that, The calibration plate (1) is used to ensure that the camera is always directly above the wafer (9) to be photographed during shooting.

7. The detection method according to claim 5, characterized in that, After the blue film (10) is stretched, the blue film (10) expands, and the vent (8) is used to remove the air between the blue film (10) and the detection device.

8. The detection method according to claim 5, characterized in that, The diffuser plate (3) is used to uniformly pass the light source emitted by the circuit board (5) through the slit of the wafer (9).

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