Wafer defect inspection machine

Abstract

The utility model relates to a wafer defect inspection machine. The wafer defect inspection machine comprises a controller; the machine table is provided with a wafer feeding station; the pre-positioning device is used for adjusting the position of the wafer; the macroscopic detection device comprises a front surface detection mechanism and a back surface detection mechanism, and the front surface detection mechanism is used for adsorbing the back surface of the wafer and driving the wafer to rotate; the back surface detection mechanism is used for adsorbing the back surface of the wafer and driving the wafer to turn over; and the moving device comprises a moving mechanism and a pick-up piece used for adsorbing the wafer, and the moving mechanism drives the pick-up piece to move among the feeding station, the pre-positioning device and the macroscopic inspection device. According to the utility model, the wafer can be directly grabbed for inspection, and the overturning inspection of the wafer is convenient.

Description

Technical Field

[0001] This utility model relates to the field of wafer processing auxiliary equipment technology, and in particular to a wafer defect inspection machine. Background Technology

[0002] After wafers (DIEs) are diced in batches on a wafer, surface defects of the wafers and the wafers on them need to be inspected. Due to factors such as the angle of the light source and the type of defect, some wafer surface defects are not obvious and difficult to see clearly with a camera. Therefore, many manufacturers still use manual visual inspection for wafer surface defects. Furthermore, because direct human contact with wafers is not allowed during wafer processing, wafer surface defect inspection relies on mechanical equipment to handle the wafers. Therefore, most existing manual visual inspection methods involve: a robotic arm removing the wafer from the fodder bin (FOUP / FOSB) and placing it on a dedicated tray; the tray is then transported to a designated rotary station, where an operator performs visual inspection by rotating the station. The use of a carrier tray undoubtedly makes wafer transport more complicated and hinders inspection of the back side of the wafer. Moreover, if the wafer needs to be flipped for inspection, it must first be removed from the carrier tray, flipped, and then put back on the carrier tray. After the back side of the wafer is inspected, it must be flipped back to the front side for easy storage and organization. The operation is cumbersome, and the associated flipping mechanism is also relatively complex. Utility Model Content

[0003] The purpose of this invention is to provide a wafer defect inspection machine that can directly pick up wafers for inspection and facilitate wafer flipping for inspection.

[0004] To achieve the above objectives, this utility model discloses a wafer defect inspection machine, which includes:

[0005] The machine is equipped with a loading station, which is used to position and place the material box, or the loading station cooperates with the output end of an external wafer transfer device to perform wafer positioning.

[0006] A pre-positioning device is disposed on the machine platform, and the pre-positioning device is used to adjust the position of the wafer;

[0007] A macroscopic inspection device is installed on the machine platform. The macroscopic inspection device includes a front inspection mechanism and a back inspection mechanism. The front inspection mechanism is used to adsorb the back side of the wafer and drive the wafer to rotate. The back inspection mechanism is used to adsorb the back side of the wafer and drive the wafer to flip.

[0008] A moving device is provided on the machine base. The moving device includes a moving mechanism and a pick-up component for adsorbing wafers. The moving mechanism drives the pick-up component to move between the loading station, the pre-positioning device and the macroscopic inspection device.

[0009] The controller connects the pre-positioning device, the macroscopic inspection device, and the moving device.

[0010] After the above setup, the moving device picks up the wafers at the loading station and places them on the pre-positioning device. The pre-positioning device adjusts the wafer's position, such as centering and orienting it, to ensure a uniform wafer orientation. This prevents wafer misalignment and potential collisions with the equipment during subsequent visual inspection, and ensures the wafer is accurately placed in the designated position after inspection. After pre-positioning, the moving device moves the wafer to the front inspection mechanism, where the front side can be visually inspected. After the front inspection is complete, the front inspection mechanism resets, and the back inspection mechanism picks up the wafer from the front and flips it, allowing for quick and easy visual inspection of the back side. After the back inspection is complete, the back inspection mechanism resets and returns the wafer to the front inspection mechanism, where the moving device removes the wafer. With the above setup, macroscopic inspection of wafers does not require a carrier tray, which simplifies the overall components of the machine, makes wafer transfer more convenient, and allows for a more compact machine layout, thus reducing the machine's footprint.

[0011] Preferably, the front inspection mechanism includes a vacuum adsorption stage, a first rotating assembly, and a second rotating assembly. The first rotating assembly drives the vacuum adsorption stage to rotate, and the second rotating assembly drives the first rotating assembly to rotate. The rotating surface of the first rotating assembly is a vertical surface, and the rotating surface of the vacuum adsorption stage is perpendicular to the rotating surface of the first rotating assembly. With this configuration, the wafer can be stably gripped by the vacuum adsorption stage, preventing wafer displacement. Furthermore, by incorporating the first and second rotating assemblies, the wafer can not only rotate horizontally but also tilt, allowing the incident light angle to be passively changed, which facilitates the detection of subtle defects.

[0012] Preferably, the front inspection mechanism further includes a third rotating component, which drives the second rotating component to rotate horizontally. This configuration allows the tilted wafer to rotate horizontally, thereby achieving a wider range of wafer angle adjustments and facilitating the detection of less noticeable defects.

[0013] Preferably, the front inspection mechanism further includes a first lifting component, which drives a first rotating component and a second rotating component to move up and down synchronously; or, the first lifting component drives a first rotating component, a second rotating component, and a third rotating component to move up and down synchronously. By providing the first lifting component, the front inspection mechanism can be lowered when the back inspection mechanism picks up the wafer, thus avoiding interference with the wafer picked up by the back inspection mechanism.

[0014] Preferably, the back-side inspection mechanism includes a second lifting component, a fourth rotating component, and a vacuum adsorption arm. The second lifting component drives the fourth rotating component to move up and down, and the fourth rotating component drives the vacuum adsorption arm to rotate. Normally, the vacuum adsorption arm is located below the front-side inspection mechanism, and the vacuum adsorption arm is offset from the front-side inspection mechanism. During wafer front-side inspection, the vacuum adsorption arm is positioned below the front-side inspection mechanism (vacuum adsorption stage), preventing interference with the wafer's rotation and sway. After the front-side inspection is completed, the front-side inspection mechanism resets, and the vacuum adsorption arm rises to adsorb the back side of the wafer. The vacuum adsorption arm then continues to rise to avoid collisions with the front-side inspection mechanism when the wafer is flipped (at this time, the vacuum adsorption stage can also be lowered to avoid collisions). This back-side inspection mechanism has a simple structure and occupies a small area. Furthermore, the vacuum adsorption arm reduces wafer obstruction.

[0015] Preferably, the system further includes a first control mechanism for manipulating the actions of the front inspection mechanism and / or the back inspection mechanism, the first control mechanism being connected to the controller. By providing the first control mechanism, the wafer's orientation can be easily adjusted for convenient inspection.

[0016] Preferably, the loading station is used to position and place the wafer tray. The loading station is equipped with a first photoelectric sensor for detecting the presence of a wafer tray, and the pick-up device is equipped with a second photoelectric sensor for detecting the wafer. The first and second photoelectric sensors are connected to a controller. With this configuration, wafers can be continuously loaded simply by periodically replacing the wafer tray. Loading is convenient, the machine is relatively independent, and it is beneficial for site layout. By using the first photoelectric sensor to detect the presence of a wafer tray and the second photoelectric sensor to detect the wafer, reliable wafer picking can be ensured.

[0017] Preferably, at least one pickup element is provided, and the moving mechanism includes a third lifting component, a fifth rotating component, and telescopic components corresponding to each pickup element. The third lifting component drives the fifth rotating component to move up and down, the fifth rotating component drives all telescopic components to rotate horizontally synchronously, and the telescopic components drive the pickup elements to move telescopically. The pickup elements are arranged at intervals in the vertical direction, and the telescopic directions of the pickup elements are parallel to each other. With this configuration, the moving mechanism has a small footprint, is flexible in movement, and improves wafer transfer efficiency by simultaneously gripping at least one wafer.

[0018] Preferably, the device further includes a microscopic inspection apparatus, which comprises an XY-axis moving platform, a microscope, and a display screen for real-time display of the microscope image. Both the microscope and the display screen are connected to a controller. The microscope is positioned above the XY-axis moving platform, which has a placement stage for placing the wafer. The moving mechanism drives a pick-up component to move to the placement stage. By moving the wafer under the microscope using the XY-axis moving platform, and by examining the defects of the wafer or wafer under the microscope and displaying them on the screen, the defects and their extent can be more clearly identified.

[0019] Preferably, the XY-axis moving platform is an electrically controlled platform, further comprising a second control mechanism for controlling the movement of the XY-axis moving platform, both the XY-axis moving platform and the second control mechanism being connected to a controller; alternatively, the XY-axis moving platform is a manually controlled platform, the machine base being equipped with a reset detection element for detecting whether the XY-axis moving platform has been reset, the XY-axis moving platform being equipped with a trigger element for triggering the reset detection element, and the reset detection element being connected to the controller. The electrically controlled XY-axis moving platform can achieve automatic reset, while the manually controlled XY-axis moving platform uses the reset detection element to inform the controller whether the XY-axis moving platform has been reset, thus preventing the wafer from being transferred to an unreset XY-axis moving platform.

[0020] This utility model has the following beneficial effects:

[0021] This invention uses a moving device to pick up wafers from the loading station and place them onto a pre-positioning device. The pre-positioning device adjusts the wafer's position, such as centering and orienting it, to ensure a uniform wafer orientation. This prevents collisions between the wafer and the equipment during subsequent visual inspection due to misalignment, and ensures the wafer is accurately placed in its designated position after inspection. After pre-positioning, the moving device moves the wafer to the front inspection mechanism, where a manual visual inspection of the front side is performed. After the front inspection is complete, the front inspection mechanism resets, and the back inspection mechanism picks up the wafer from the front and flips it, allowing for a quick and easy manual visual inspection of the back side. After the back inspection is complete, the back inspection mechanism resets and returns the wafer to the front inspection mechanism, from which the moving device removes it. This design eliminates the need for a carrier tray for macroscopic wafer inspection, simplifying the machine's components, facilitating wafer transport, and allowing for a more compact layout, thus reducing the machine's footprint. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the present invention.

[0023] Figure 2This is a schematic diagram of the hidden part of the machine tool of this utility model.

[0024] Figure 3 This is a schematic diagram of the material loading station and the material box.

[0025] Figure 4 This is a schematic diagram of a macroscopic inspection device.

[0026] Figure 5 This is a schematic diagram from another perspective of the macroscopic inspection device.

[0027] Figure 6 This is a schematic diagram of a microscopic inspection device.

[0028] Explanation of symbols for main components:

[0029] Machine base 10, loading station 11, first photoelectric sensor 12, reset detection element 13;

[0030] Mobile device 20, mobile mechanism 21, picking component 22, telescopic assembly 23;

[0031] Pre-positioning device 30;

[0032] Macroscopic inspection device 40, front inspection mechanism 41, back inspection mechanism 42, vacuum adsorption stage 43, first rotating component 44, second rotating component 45, third rotating component 46, first lifting component 47, second lifting component 48, fourth rotating component 49, vacuum adsorption arm 4a, touch screen 4b, crank handle 4c.

[0033] Microscopic inspection device 50, XY axis moving platform 51, microscope 52, display screen 53, placement stage 54, trigger 55;

[0034] Material box 61, wafer 62. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.

[0036] like Figures 1-6 As shown, this utility model discloses a wafer defect inspection machine, which includes: a machine base 10, a controller, a pre-positioning device 30, a macroscopic inspection device 40, a microscopic inspection device 50, and a moving device 20. A loading station 11 is provided on the machine base 10, which is used to position and place a material box 61. A first photoelectric sensor 12 for detecting the material box 61 is provided on the loading station 11, and the first photoelectric sensor 12 is connected to the controller. Of course, the loading station 11 can also cooperate with the output of an external wafer 62 conveying device for wafer 62 positioning.

[0037] The moving device 20 is used to grip the wafer 62 and transfer it to various devices. The loading station 11, the pre-positioning device 30, the macroscopic inspection device 40, and the microscopic inspection device 50 are all located on the outer periphery of the moving device 20 to allow for a compact machine layout. The moving device 20 includes a moving mechanism 21 and at least one picking member 22. The picking member 22 is a fork arm with a vacuum adsorption function, and the start and stop of the vacuum adsorption function of the picking member 22 is controlled by a controller. The fork arm does not obstruct the central area of ​​the wafer 62 to facilitate the transfer of the wafer 62 to the macroscopic inspection device 40 and the microscopic inspection device 50. In this case, two picking members 22 are provided. In addition, a second photoelectric sensor can be provided on the fork arm to detect whether it has reliably gripped the wafer 62. The second photoelectric sensor is connected to the controller.

[0038] The moving mechanism 21 includes a third lifting component, a fifth rotating component, and telescopic components 23 corresponding to the picking components 22. The third lifting component drives the fifth rotating component to move up and down, the fifth rotating component drives all the telescopic components 23 to rotate horizontally synchronously, and the telescopic components 23 drive the picking components 22 to move telescopically to avoid mutual interference and collisions with other devices. The picking components 22 are arranged at intervals in the vertical direction, and the telescopic directions of the picking components 22 are parallel to each other for easy control. The electrical components of the moving mechanism 21 are connected to a controller. This type of moving mechanism 21 has a small footprint, is flexible in movement, and improves the transfer efficiency of the wafers 62 by simultaneously gripping two wafers 62. The moving mechanism 21 can adopt the wafer 62 robotic arm device described in the utility model patent with publication number CN214238251U.

[0039] The pre-positioning device 30 is mounted on the machine tool 10 and is used to adjust the position of the wafer 62 so that the wafer 62 can be presented in a uniform posture. The electrical components of the pre-positioning device 30 are connected to the controller. The pre-positioning device 30 is prior art, and the wafer 62 pre-positioning device 30 described in the utility model patent with announcement number CN213816104U can be used, and will not be described in detail here.

[0040] The macroscopic inspection device 40 includes a front inspection mechanism 41 and a back inspection mechanism 42. The front inspection mechanism is used to adsorb the back side of the wafer 62 and drive the wafer 62 to rotate, while the back inspection mechanism 42 is used to adsorb the back side of the wafer 62 and drive the wafer 62 to flip.

[0041] Specifically, the front inspection mechanism 41 includes a vacuum adsorption stage 43, a first rotating assembly 44, a second rotating assembly 45, a third rotating assembly 46, and a first lifting assembly 47. The vacuum adsorption function of the vacuum adsorption stage 43 is controlled by a controller. The third rotating assembly 46 is mounted on the machine base 10 and drives the first lifting assembly 47 to rotate horizontally. The first lifting assembly 47 drives the second rotating assembly 45 to move up and down, the second rotating assembly 45 drives the first rotating assembly 44 to rotate, and the first rotating assembly 44 drives the vacuum adsorption stage 43 to rotate. The rotation surface of the first rotating assembly 44 is a vertical surface, and the rotation surface of the vacuum adsorption stage 43 is perpendicular to the rotation surface of the first rotating assembly 44. In this case, the first rotating assembly 44 is a hollow stepper motor, the second rotating assembly 45 is a combination of a motor and a belt assembly (one pulley is connected to the motor shaft, and the other pulley is connected to the first rotating assembly 44 and rotates synchronously), and the third rotating assembly 46 is an electric turntable. The first lifting assembly 47 is a combination of a motor, a belt assembly, and a guide rail assembly. The first rotating component 44, the second rotating component 45, the third rotating component 46, and the first lifting component 47 are all connected to the controller.

[0042] The back-side inspection mechanism 42 includes a second lifting assembly 48, a fourth rotating assembly 49, and a vacuum suction arm 4a. The second lifting assembly 48 drives the fourth rotating assembly 49 to move up and down, and the fourth rotating assembly 49 drives the vacuum suction arm 4a to rotate. The vacuum suction arm 4a is located above the front-side inspection mechanism 41. The vacuum suction arm 4a does not obstruct the central area of ​​the wafer 62 to facilitate the transition of the wafer 62 from the vacuum suction stage 43 to the vacuum suction arm 4a. At the same time, the vacuum suction arm 4a is designed with as much open space as possible to minimize obstruction of the wafer 62. The vacuum suction function of the vacuum suction arm 4a is controlled by a controller. The second lifting assembly 48 is the same as the first lifting assembly 47, and the fourth rotating assembly 49 is the same as the second rotating assembly 45, and will not be described again. The second lifting assembly 48 and the fourth rotating assembly 49 are connected to the controller.

[0043] The front-side inspection of wafer 62 is the most critical. To facilitate the operation of the front-side inspection mechanism 41, a first control mechanism is provided for controlling its movement. This first control mechanism may include a touchscreen 4b and a crank 4c, and is connected to a controller. By controlling the front-side inspection mechanism 41, the wafer 62 it grips can be tilted and rotated at multiple angles, making it easier to detect some subtle defects. Alternatively, the first control mechanism can also control the back-side inspection mechanism 42 to adjust the flipping angle of the wafer 62. Back-side inspection of wafer 62 can detect defects that are difficult to spot from the front, thereby improving the reliability of surface defect detection on wafer 62.

[0044] The moving mechanism 21 delivers the pre-positioned wafer 62 to the front inspection mechanism 41. The second lifting component 48 and the fourth rotating component 49 lower and flatten the vacuum adsorption arm 4a to avoid interfering with the operation of the front inspection mechanism 41 and colliding with the wafer 62. When the moving mechanism 21 delivers the pre-positioned wafer 62 to the front inspection mechanism 41, the pickup component 22 stops vacuum adsorption, while the vacuum adsorption stage 43 starts vacuum adsorption, thereby transferring the wafer 62 to the front inspection mechanism 41. After the front inspection is completed, the controller controls the front inspection mechanism 41 to reset, the vacuum adsorption arm 4a moves up to contact the wafer 62 and starts vacuum adsorption. At this time, the vacuum adsorption stage 43 stops vacuum adsorption, thereby transferring the wafer 62 to the back inspection mechanism 42. Afterward, the vacuum adsorption stage 43 lowers, and the vacuum adsorption arm 4a can also be raised simultaneously to avoid interfering with the flipping of the wafer 62. After the back side inspection of wafer 62 is completed, the controller controls the back side inspection mechanism 42 to flip wafer 62 back to face up, and drives the vacuum adsorption arm 4a to move down while the vacuum adsorption stage 43 is raised, so that wafer 62 is placed on the vacuum adsorption stage 43 again and adsorbed stably, waiting for the moving device 20 to come over to grab and remove wafer 62.

[0045] The microscopic inspection device 50 includes an XY-axis moving platform 51, a microscope 52, and a display screen 53 for real-time display of the microscope 52's image. Both the microscope 52 and the display screen 53 are connected to a controller. The microscope 52 is positioned above the XY-axis moving platform 51. The XY-axis moving platform 51 has a placement stage 54 for placing the wafer 62. The moving mechanism 21 drives the pick-up component 22 to move to the placement stage 54, thereby transferring the wafer 62 onto the stage 54. The placement stage 54 preferably has a vacuum adsorption function, which is controlled by the controller. After macroscopic inspection of the wafer 62, the moving device 20 moves the wafer 62 from the vacuum adsorption stage 43 to the placement stage 54. The wafer 62 is moved under the microscope 52 via the XY-axis moving platform 51. Defects on the wafer 62 or the wafer are viewed through the microscope 52 and displayed on the display screen 53. The magnified display facilitates viewing and better clarifies the defects and their extent.

[0046] In this case, the XY-axis moving platform 51 is a manually controlled platform. Additionally, a reset detection element 13 is provided on the machine tool 10 to detect whether the XY-axis moving platform 51 has been reset. A trigger element 55 is provided on the XY-axis moving platform 51 to trigger the reset detection element 13. The reset detection element 13 can be a contact switch and is connected to the controller. The reset detection element 13 informs the controller whether the XY-axis moving platform 51 has been reset, thus preventing the wafer 62 from being transferred to an unreset XY-axis moving platform 51. Alternatively, the XY-axis moving platform 51 can be an electrically controlled platform. Furthermore, a second control mechanism is provided to control the movement of the XY-axis moving platform 51. Both the XY-axis moving platform 51 and the second control mechanism are connected to the controller. The second control mechanism can be a button or a touchscreen 4b.

[0047] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model should be included within the protection scope of the present utility model.

Claims

1. A wafer defect inspection machine, characterized in that, include: The machine is equipped with a loading station, which is used to position and place the material box, or the loading station cooperates with the output end of an external wafer transfer device to perform wafer positioning. A pre-positioning device is disposed on the machine platform, and the pre-positioning device is used to adjust the position of the wafer; A macroscopic inspection device is installed on the machine platform. The macroscopic inspection device includes a front inspection mechanism and a back inspection mechanism. The front inspection mechanism is used to adsorb the back side of the wafer and drive the wafer to rotate. The back inspection mechanism is used to adsorb the back side of the wafer and drive the wafer to flip. A moving device is provided on the machine base. The moving device includes a moving mechanism and a pick-up component for adsorbing wafers. The moving mechanism drives the pick-up component to move between the loading station, the pre-positioning device and the macroscopic inspection device. The controller connects the pre-positioning device, the macroscopic inspection device, and the moving device.

2. The wafer defect inspection machine according to claim 1, characterized in that: The front inspection mechanism includes a vacuum adsorption stage, a first rotating component, and a second rotating component. The first rotating component drives the vacuum adsorption stage to rotate, and the second rotating component drives the first rotating component to rotate. The rotating surface of the first rotating component is a vertical surface, and the rotating surface of the vacuum adsorption stage is perpendicular to the rotating surface of the first rotating component.

3. The wafer defect inspection machine according to claim 2, characterized in that: The front inspection mechanism also includes a third rotating component, which drives the second rotating component to rotate horizontally.

4. The wafer defect inspection machine according to claim 2 or 3, characterized in that: The front inspection mechanism further includes a first lifting component, which drives a first rotating component and a second rotating component to move up and down synchronously, or the first lifting component drives a first rotating component, a second rotating component, and a third rotating component to move up and down synchronously.

5. The wafer defect inspection machine according to claim 1, characterized in that: The back inspection mechanism includes a second lifting component, a fourth rotating component, and a vacuum adsorption arm. The second lifting component drives the fourth rotating component to move up and down, and the fourth rotating component drives the vacuum adsorption arm to rotate. Under normal conditions, the vacuum adsorption arm is located below the front inspection mechanism, and the vacuum adsorption arm is offset from the front inspection mechanism.

6. The wafer defect inspection machine according to claim 1, characterized in that: It also includes a first control mechanism for manipulating the operation of the front inspection mechanism and / or the back inspection mechanism, the first control mechanism being connected to the controller.

7. The wafer defect inspection machine according to claim 1, characterized in that: The loading station is used to position and place the material box. The loading station is equipped with a first photoelectric sensor for detecting whether there is a material box. The picking unit is equipped with a second photoelectric sensor for detecting the wafer. The first photoelectric sensor and the second photoelectric sensor are connected to the controller.

8. The wafer defect inspection machine according to claim 1, characterized in that: The pickup component is provided with at least one, and the moving mechanism includes a third lifting component, a fifth rotating component, and telescopic components corresponding to the pickup components. The third lifting component drives the fifth rotating component to move up and down, the fifth rotating component drives all the telescopic components to rotate horizontally synchronously, and the telescopic components drive the pickup components to move telescopically. The pickup components are arranged at intervals in the vertical direction, and the telescopic directions of the pickup components are parallel to each other.

9. The wafer defect inspection machine according to claim 1, characterized in that: It also includes a microscopic inspection device, which includes an XY-axis moving platform, a microscope, and a display screen for displaying microscope images in real time. The microscope and the display screen are both connected to a controller. The microscope is positioned above the XY-axis moving platform, which is equipped with a placement stage for placing wafers. The moving mechanism can drive the pick-up component to move to the placement stage.

10. The wafer defect inspection machine according to claim 9, characterized in that: The XY-axis moving platform is an electrically controlled platform, and also includes a second control mechanism for controlling the movement of the XY-axis moving platform. Both the XY-axis moving platform and the second control mechanism are connected to a controller. Alternatively, the XY-axis moving platform is a manually controlled platform. The machine base is provided with a reset detection element for detecting whether the XY-axis moving platform has been reset. The XY-axis moving platform is provided with a trigger element for triggering the reset detection element. The reset detection element is connected to the controller.

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