TWI854391B - Wafer inspection method and device thereof - Google Patents

Abstract

A wafer inspection method and device are disclosed. The wafer inspection method includes: providing a wafer device including a carrier, a robot arm, a working platform, an inspection seat, a light source group and cameras; moving the robot arm and clamping the wafer to the inspection seat; moving the inspection seat to a capture plane; starting the light source group and the cameras to illuminate the capture plane and capture macro images of the wafer; performing a macro image analysis; moving the inspection seat; and moving the robot arm, and clamping the wafer to the carrier. This disclosure also discloses a wafer inspection device.

Description

Wafer inspection method and device

The present invention relates to a semiconductor testing device, and more particularly to a wafer testing method and a device thereof.

In the traditional semiconductor process, standard defect detection is performed by operators visually inspecting the wafer surface and judging defects, which is prone to misjudgment. In response to this, most current wafer inspection devices use automated optical inspection (AOI) to automate defect detection.

Furthermore, as shown in FIG1 , the automatic optical inspection equipment is provided with a wafer seat 20a on a platform 10a, and a camera module 30a and a light source 40a are installed corresponding to the wafer seat 20a. When the wafer is transferred to the wafer seat 20a by the robot, the light source 40a will illuminate the surface of the wafer, and the camera module will take a picture of the wafer surface to capture an image to determine whether there are defects on the wafer surface.

However, the aforementioned wafer inspection device is used to inspect whether there are defects on the front side of the wafer. If it is necessary to inspect the back side of the wafer at the same time, the inspection must be completed by rotating the wafer seat 20a. However, the rotation of the wafer seat 20a will generate vibrations that will cause damage to the wafer, and the light and shadow during the flipping process will easily cause misjudgment. In addition, the rotation of the wafer seat 20a will extend the inspection time, resulting in a slower inspection speed.

One purpose of the present invention is to provide a wafer inspection method and device to shorten the inspection time, avoid damage to the wafer and improve the yield.

In order to achieve the above-mentioned purpose, the present invention is a wafer inspection method, which includes the following steps: a) providing a wafer device, including a carrier for carrying wafers, a robot arm arranged on one side of the carrier, a workbench with an imaging plane, a detection seat arranged on the workbench and capable of moving to the imaging plane position, a light source group arranged corresponding to the imaging plane position, and a plurality of cameras arranged corresponding to the light source group; b) moving the robot arm and clamping the wafer to the detection seat; c) moving the detection seat to the imaging plane position; d) starting the light source group and the cameras to illuminate the imaging plane position and capture a wafer macroscopic image; e) performing a macroscopic analysis on the wafer macroscopic image; f) moving the detection seat to one side of the carrier; and g) moving the robot arm and clamping the wafer to the carrier.

In order to achieve the above-mentioned purpose, the present invention is a wafer inspection device, including a carrier, a machine arm, a workbench, a detection seat, a light source group and a plurality of cameras. The carrier is used to carry the wafer. The machine arm is arranged on one side of the carrier, and the machine arm is used to clamp and move the wafer. The workbench is arranged on one side of the machine arm and has an imaging plane. The detection seat is movably arranged on the workbench and can be moved to the imaging plane position, and the detection seat includes a movable table for carrying the wafer. The light source group is arranged on the workbench corresponding to the imaging plane position, and the light source group includes a first light source, a second light source and a third light source which are separately arranged. The third light source is arranged perpendicular to the imaging plane. The first light source has a first irradiation direction, and the first irradiation direction has a first light source angle relative to the horizontal direction of the imaging position. The second light source has a second irradiation direction, and the second irradiation direction has a second light source angle relative to the horizontal direction of the imaging position. The range of the first and second light source angles is set to be not less than 5 degrees and not more than 80 degrees. The plurality of cameras includes a first camera and a second camera arranged on both sides of the third light source. The first camera and the third light source are arranged at a first photographic angle, and the second camera and the third light source are arranged at a second photographic angle. The range of the first and second photographic angles is set to be not less than 0 degrees and not more than 60 degrees.

Compared to the prior art, the wafer inspection method of the present invention first provides a wafer device, and sets a light source group including a first light source, a second light source and a third light source which are separately set. The third light source is set perpendicular to the imaging plane. The first and second light sources have a first and second light source angle relative to the horizontal direction of the imaging position, and the range of the first and second light source angle is set to be not less than 5 degrees and not more than 80 degrees. In addition, the range of the photography angle of the first and second cameras and the third light source is set to be not less than 0 degrees and not more than 60 degrees, thereby avoiding shadows from appearing on the captured wafer macro image for analysis, and through macroscopic inspection (Macro Furthermore, the wafer inspection process of the present invention does not need to rotate the wafer to obtain a clear image, thereby reducing the inspection time and the possibility of misjudgment. Furthermore, since the inspection process of the present invention does not need to rotate the wafer by a machine arm, the wafer can be kept in a flat state and the wafer can be avoided from being damaged, thereby reducing damage to the wafer and improving the yield.

The detailed description and technical contents of the present invention are described below with reference to the accompanying drawings. However, the accompanying drawings are only provided for reference and description and are not intended to limit the present invention.

Please refer to Figures 2 and 3, which are a plan view and a side view of the wafer inspection device of the present invention. The present invention is a wafer inspection device 1, including a carrier 10, a robot arm 20, a workbench 30, a detection base 40, a light source group 50 and a plurality of cameras 60. The carrier 10 is used to carry the wafer 2 to be tested and the wafer 2 that has completed the inspection. The robot arm 20 is arranged between the carrier 10 and the workbench 30, and is used to clamp the wafer 2 to be tested on the carrier 10 to the workbench 30, and clamp the wafer that has completed the inspection on the workbench 30 and put it back on the carrier 10. In addition, the light source group 50 and the plurality of cameras 60 are installed on the workbench 30 to capture the image of the wafer 2 to be tested for inspection.

The robot arm 20 is disposed on one side of the carrier 10. The robot arm 20 has a Y-shaped clamp 21 for clamping and moving the wafer 2.

The workbench 30 is disposed on one side of the robot arm 20 and has an imaging plane 31. Moreover, the detection seat 40 is movably disposed on the workbench 30 and moved to the imaging plane 31. Preferably, the detection seat 40 includes a movable table 41 capable of carrying the wafer 2, and the movable table 41 is configured to be able to be lifted and rotated relative to the detection seat 40, so as to facilitate the image capture operation of the wafer 2 on the movable table 41.

The light source group 50 is arranged on the workbench 30 corresponding to the position of the imaging plane 31. The light source group 50 includes a first light source 51, a second light source 52 and a third light source 53 which are separately arranged. The third light source 53 is arranged perpendicular to the imaging plane 31. The first light source 51 and the second light source 52 are auxiliary lights. The first light source 51 has a first irradiation direction L1, and the first irradiation direction L1 has a first light source angle A1 relative to the horizontal direction of the imaging position 31. In addition, the second light source 52 has a second irradiation direction L2, and the second irradiation direction L2 has a second light source angle A2 relative to the horizontal direction of the imaging position 31. The angle setting range of the first light source angle A1 and the second light source angle A2 is not less than 5 degrees and not more than 80 degrees, and the ranges of the first and second light source angles A1 and A2 are not necessarily the same.

Specifically, the light source group 50 is disposed on a side of the workbench 30 away from the carrier 10. In addition, the light source group 50 includes at least two linear light sources, such as ring light, coaxial light, bar light, flat light, RGB light, spot light, ultraviolet light, or infrared light.

It should be noted that the angles of the first light source angle A1 and the second light source angle A2 can be adjusted according to actual conditions such as design parameters such as wafer size to obtain the required illumination, thereby obtaining a clear image.

The plurality of cameras 60 includes a first camera 61 and a second camera 62 which are separately arranged. In addition, the first camera 61 is arranged at a first camera angle B1 with the third light source 53, and the second camera 62 is arranged at a second camera angle B2 with the third light source 53. The angle setting range of the first camera angle B1 and the second camera angle B2 is not less than 0 degrees and not more than 60 degrees, and the angle ranges of the first camera angle B1 and the second camera angle B2 are not necessarily the same.

It is worth noting that the first camera 61 and the second camera 62 can be disposed around the third light source 53 and only need to be disposed within the angle setting range that conforms to the first photographing angle B1 and the second photographing angle B2.

It should be noted that the angles of the first camera angle B1 and the second camera angle B2 can be adjusted according to actual conditions such as wafer film thickness and other design parameters. In addition, the cameras 60 can include area scan cameras, line scan cameras or 3D cameras.

In actual use, the first light source 51 and the second light source 52 can be symmetrically arranged. In addition, the angle of the first light source 51 relative to the first camera 61 and the angle of the second light source 52 relative to the second camera 62 can be set to be different.

It should also be noted that the present invention avoids shadows on the wafer 2 by selecting the light source type of the light source group 50 and adjusting the angle settings of the cameras 60, so that the image of the wafer 2 can be accurately captured and analyzed to perform macro inspection and determine whether the wafer 2 has defects. Therefore, the wafer inspection device 1 of the present invention can obtain clear images without rotating the wafer 2.

Preferably, in one use condition, the angle of the first photographing angle B1 and the second photographing angle B2 can be set to 10 degrees, and the angle of the first photographing angle B1 and the second photographing angle B2 is set to 25 degrees. In another use condition, the angle of the first photographing angle B1 and the second photographing angle B2 can be set to 15 degrees, and the angle of the first photographing angle B1 and the second photographing angle B2 is set to 30 degrees, thereby providing a wafer inspection device 1 that meets the needs of users.

In this embodiment, the wafer inspection device 1 further includes a bottom camera 70 and a bottom light source 72, and the bottom camera 70 can be superimposed on the bottom light source 72. In addition, an opening 410 is correspondingly provided at the bottom side of the movable table 41. Accordingly, under the illumination of the bottom light source 72, the bottom camera 70 can capture images of the back side of the wafer 2 through the opening 410 and perform inspection.

It should be noted that the number and position of the bottom camera 70 and the bottom light source 72 are not limited and can be adjusted according to actual usage conditions.

Accordingly, the wafer inspection device 1 of the present invention can implement a wafer inspection method, the steps of which include: a) providing a wafer device 1, including a carrier 10 for carrying a wafer 2, a robot arm 20 disposed on one side of the carrier 10, a workbench 30 having an imaging plane 31, a detection seat 40 disposed on the workbench 30 and capable of moving to the position of the imaging plane 31, a light source group 50 disposed corresponding to the position of the imaging plane 31, and a plurality of cameras 60 disposed corresponding to the light source group 50; b) moving the robot arm 20 and clamping the wafer 2 to the detection seat 40; c) moving the detection seat 40 to the position of the imaging plane 31; d) Start the light source group 50 and the cameras 60 to illuminate the imaging plane 31 and capture the wafer macro image; e) perform macro analysis on the wafer macro image; f) move the inspection base 40 to one side of the carrier 10; and g) move the robot arm 20 and clamp the wafer 2 to the carrier 10.

In an embodiment of the present invention, the wafer inspection device 1 further includes a micro camera 80 and a micro light source 81 for performing micro inspection. The micro camera 80 and the micro light source 81 are disposed on the workbench 30 near one side of the carrier 10 .

Accordingly, the wafer inspection method of the present invention further includes activating the microscopic camera 80 and a microscopic light source 81 to capture wafer microscopic images and perform microscopic analysis.

It is worth noting that, in actual use, the wafer inspection device 1 of the present invention can be equipped with light sources in different areas according to customer needs to improve the accuracy of inspection.

Please also refer to Figures 4 to 7, which are schematic diagrams of the operation of the wafer inspection device of the present invention for performing a macroscopic inspection process. Please refer to Figures 4 and 5, when the wafer inspection device 1 of the present invention performs inspection, the machine arm 20 first clamps a wafer 2 to be inspected from the carrier 10, and moves the wafer 2 to the inspection seat 40 and positions it. Referring again to Figures 6 and 7, the inspection seat 40 with the wafer 2 placed thereon can be moved to the imaging plane 31 position via a conveyor belt for transportation, and image capture is performed. In this embodiment, the imaging plane 31 position is located directly below the third light source 53, and this position is the image capture area for macroscopic inspection of the present invention.

Please continue to refer to Figures 8 to 10, which are schematic diagrams of the microscopic inspection process of the wafer inspection device of the present invention. Please refer to Figure 8, when the wafer inspection device 1 of the present invention performs microscopic inspection, the inspection seat 40 carrying the wafer 2 will move from the imaging plane 31 position (macroscopic inspection area) to the microscopic inspection area 32. In this embodiment, the microscopic inspection area 32 is where the microscopic camera 80 and the microscopic light source 81 are set, and is located on the workbench 30 close to the side of the carrier 10.

Please continue to refer to FIG9 . During microscopic inspection, the movable table 41 carrying the wafer 2 can be extended from the inspection seat 40 and rotated to facilitate the microscopic camera 80 to capture images of specific positions. Please refer to FIG10 . After the microscopic camera 80 completes image capture, the movable table 41 is lowered to its original position in the inspection seat 40 , and the wafer 2 is positioned in the inspection seat 40 .

Please refer to Figures 11 and 12, which are schematic diagrams of the wafer inspection device of the present invention completing the inspection process. As shown in Figure 11, when the wafer 2 completes the inspection operation, the robot arm 20 will clamp the wafer 2 on the inspection seat 40. Please refer to Figure 12 again, finally, the robot arm 20 moves the wafer 2 to the position on the carrier 10 where the inspection has been completed. Accordingly, the wafer inspection device 1 completes the macroscopic and microscopic inspection of the wafer 2.

The above description is only a preferred embodiment of the present invention and is not intended to define the patent scope of the present invention. Other equivalent variations that utilize the patent spirit of the present invention should all fall within the patent scope of the present invention.

10a: platform 20a: wafer seat 30a: camera module 40a: light source 1: wafer inspection device 10: carrier 20: machine arm 21: Y-type clamp 30: workbench 31: imaging plane 32: microscopic inspection area 40: inspection seat 41: movable table 410: opening 50: light source group 51: first light source 52: second light source 53: third light source 60: camera 61: first camera 62: second camera 70: bottom camera 72: bottom light source 80: microscopic camera 81: microscopic light source L1: first irradiation direction L2: second irradiation direction A1: First light source angle A2: Second light source angle B1: First photography angle B2: Second photography angle

FIG1 is a schematic diagram showing the operation of a conventional wafer inspection device.

FIG. 2 is a schematic plan view of the wafer inspection device of the present invention.

FIG. 3 is a side view of the wafer inspection device of the present invention.

4 to 7 are schematic diagrams showing the operation of the wafer inspection device of the present invention in performing a macroscopic inspection process.

8 to 10 are schematic diagrams showing the operation of the wafer inspection device of the present invention in performing a microscopic inspection process.

11 to 12 are schematic diagrams showing the operation of the wafer inspection device of the present invention to complete the inspection process.

1: Wafer inspection device

20: Robotic arm

21: Y-type clamp

30: Workbench

31: Imaging plane

32: Microscopic detection area

40: Detection seat

41: Activity table

410: Open mouth

50: Light source group

51: The first light source

52: Second light source

53: The third light source

60: Camera

61: First Camera

62: Second camera

70: Bottom camera

72: Bottom light source

80: Micro camera

81: Microscopic light source

L1: First irradiation direction

L2: Second irradiation direction

A1: Angle of the first light source

A2: Second light source angle

B1: First camera angle

B2: Second photography angle

Claims (6)

A wafer inspection method comprises the following steps: a) providing a wafer device, comprising a carrier for carrying a wafer, a robot arm arranged on one side of the carrier, a workbench having an imaging plane, a detection seat arranged on the workbench and capable of moving to the imaging plane, a light source group arranged corresponding to the imaging plane position, and a plurality of cameras arranged corresponding to the light source group, wherein the light source group comprises a first light source, a second light source, and a third light source which are arranged above the imaging plane and are separated, the third light source being arranged perpendicular to the imaging plane, the first light source having a first irradiation direction, the first irradiation direction being relative to the imaging plane; The horizontal direction has a first light source angle, the second light source has a second irradiation direction, the second irradiation direction has a second light source angle relative to the horizontal direction of the imaging plane, and the range of the first and second light source angles is set to be not less than 5 degrees and not more than 80 degrees; b) move the machine arm and clamp the wafer to the detection seat; c) move the detection seat to the imaging plane position; d) start the light source group and the cameras, illuminate the imaging plane position and capture the wafer macroscopic image; e) perform macroscopic analysis on the wafer image; f) move the detection seat to one side of the carrier; and g) move the machine arm and clamp the wafer to the carrier. The wafer inspection method as described in claim 1, wherein in step a), the plurality of cameras include a first camera and a second camera disposed on both sides of the third light source, the first camera and the third light source are disposed at a first photographic angle, the second camera and the third light source are disposed at a second photographic angle, and the range of the first and second photographic angles is set to be not less than 0 degrees and not more than 60 degrees. As described in claim 1, in step a), the wafer device further includes a bottom camera and a bottom light source disposed below the imaging plane, the inspection seat includes a movable table for carrying the wafer, and the bottom side of the movable table is correspondingly provided with an opening. The wafer inspection method as described in claim 3, wherein in step d), the bottom camera and the bottom light source are activated simultaneously to illuminate the upper and lower sides of the imaging plane and capture images of the upper and lower surfaces of the wafer. As described in claim 1, in step a), the wafer inspection method further includes a microscopic camera and a microscopic light source, and the microscopic camera and the microscopic light source are arranged on a side of the workbench close to the carrier. The wafer inspection method as described in claim 5, wherein step f) further includes activating the microscopic camera and a microscopic light source to capture microscopic images of the wafer and perform microscopic analysis.

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