Laser thickness measuring system for chip thinning and thickness measuring method
Through the combination of laser thickness measurement system and adjustment frame, flexible adjustment of the angle of the pressurized clamp and real-time monitoring of chip thickness are achieved, solving the problems of grinding quality and inefficiency caused by the fixation of the position of the pressurized clamp in the traditional chip thinning process, and improving the grinding quality and production efficiency.
Patent Information
- Application Number
- CN202411834244.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-13
- Publication Date
- 2025-03-18
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
In the existing chip thinning process, the position of the pressurized fixture is fixed, making it difficult to adjust the degree of inclination, resulting in poor smoothness repair flexibility and low grinding quality and production efficiency.
The laser thickness measurement system is adopted to drive the angle adjustment of the pressurized fixture through the combination of the adjustment frame and the adjustment plate, and the chip thickness is monitored in real time by using the laser emitter and receiver to automatically control the operation of the grinder.
It realizes flexible adjustment of the flatness of the pressurized fixture, improves the chip grinding quality and production efficiency, and reduces human operation errors and uneven grinding problems.
Smart Images
Figure CN119635536A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of chip thinning, and in particular to a laser thickness measurement system and thickness measurement method for chip thinning. Background Art
[0002] Chip thinning is an important step in semiconductor manufacturing, which involves reducing the thickness of the chip to a set value so as to better suit the subsequent packaging and testing processes.
[0003] The existing chip thinning process uses the traditional grinding method to mount the chip to be thinned on a glass plate, which is then adsorbed onto a pressurized fixture by vacuum adsorption. Grinding fluid is then added to the grinding disc of the grinder to make the chip to be thinned on the pressurized fixture glass plate and the grinding disc of the grinder vertically aligned. The grinder is started to rotate the grinding disc and rub the surface of the chip to achieve the purpose of thinning. During the chip thinning process, the chip thickness needs to be monitored by shutting down the grinder, and the operator manually measures the thickness of each chip through a measuring microscope. After the measurement is completed, the chip is put back into the pressurized fixture to apply pressure and continue grinding through the grinding disc of the grinder.
[0004] The above-mentioned traditional grinding method is difficult to adjust the inclination of the pressurizing fixture due to the fixed position of the pressurizing fixture during the chip grinding process, thereby being unable to repair the flatness of the pressurizing fixture. The poor flexibility leads to low chip grinding quality and production efficiency. Summary of the invention
[0005] In order to help solve the problem that the position of the pressurizing clamp is fixed, it is difficult to adjust the inclination of the pressurizing clamp, thereby being unable to repair the flatness of the pressurizing clamp, the flexibility is poor, and the chip grinding quality and production efficiency are low, the present application provides a laser thickness measurement system for chip thinning, which adopts the following technical scheme: it includes a support seat and a mounting seat, the support seat is provided with a plurality of adjustment frames, and the plurality of adjustment frames are respectively slidably connected with adjustment plates, the pressurizing clamp is connected to the plurality of adjustment plates through a connecting unit, the adjustment frame is provided with an adjustment unit for driving the adjustment plate to rise and fall, and the grinder is arranged on the mounting seat and the grinding disc of the grinder corresponds to the pressurizing clamp.
[0006] In a specific implementation scheme, the adjustment unit includes an adjustment screw rotatably connected to an adjustment frame, the outer edge of the adjustment screw is threadedly connected to an adjustment nut, the adjustment plate is arranged on the adjustment nut, and the adjustment frame is provided with a first drive assembly for driving the adjustment screw to rotate.
[0007] In a specific possible implementation scheme, the adjustment frame is provided with a guide rail arranged parallel to the adjustment screw rod, a guide block matching the guide rail is slidably connected to the guide rail, and the adjustment plate is arranged on the guide block.
[0008] In a specific possible implementation scheme, a support block is provided on the adjustment frame, and the adjustment screw rod passes through the support block and is rotatably connected to the support block.
[0009] In a specific possible implementation scheme, several of the connecting units respectively include connecting rods hinged on the adjustment plate, one end of the connecting rod facing away from the adjustment plate is hinged with a connecting block, and the pressure clamps are arranged on several of the connecting blocks.
[0010] In a specific feasible implementation scheme, a first rangefinder frame and a second rangefinder frame are provided on the mounting seat, a laser transmitter is slidably connected to the first rangefinder frame, a laser receiver is slidably connected to the second rangefinder frame, a transmitting end of the laser transmitter corresponds to a receiving end of the laser receiver, and the chip to be thinned on the pressurizing fixture is located between the transmitting end of the laser transmitter and the receiving end of the laser receiver, a first sliding unit for driving the laser transmitter to slide is provided on the first rangefinder frame, and a second sliding unit for driving the laser receiver to slide is provided on the second rangefinder frame.
[0011] In a specific feasible implementation scheme, a photosensitive diode is provided on the laser receiver; when the height at which the laser receiver receives the laser is lower than a set value, the photosensitive diode is in a bright field, and the grinder grinds normally at this time; when the height at which the laser receiver receives the laser reaches a set value, the photosensitive diode becomes a dark field, and the grinder stops grinding at this time.
[0012] In a specific possible implementation scheme, the first sliding unit includes a ranging screw rotatably connected to a first ranging frame, the outer edge of the ranging screw is threadedly connected to a ranging nut matching the ranging screw, the laser transmitter is arranged on the ranging nut, and the first ranging frame is provided with a second driving component for driving the ranging screw to rotate.
[0013] In a specific implementation scheme, a guide rod parallel to the distance measuring screw is provided on the first distance measuring frame, a guide sleeve matching the guide rod is slidably connected to the outer edge of the guide rod, and the laser emitter is arranged on the guide sleeve.
[0014] In a specific embodiment, a thickness measurement method of a laser thickness measurement system for chip thinning includes:
[0015] Start the adjustment unit, and the adjustment plate drives the pressurizing fixture to adjust to the set position;
[0016] Starting the first sliding unit and adjusting the laser transmitter on the first rangefinder to a set position;
[0017] Start the second sliding unit and adjust the laser receiver on the second rangefinder to a set position;
[0018] Start the grinder to drive the grinding disc of the grinder to grind the chip to be thinned on the pressurized fixture;
[0019] Start the laser transmitter, aim the laser at the chip grinding position and emit the laser, and the laser receiver receives the laser in real time; when the height at which the laser receiver receives the laser is lower than the set value, the photodiode is in bright field, and the grinder grinds normally; when the height at which the laser receiver receives the laser reaches the set value, the photodiode becomes dark field, and the grinder stops grinding.
[0020] To sum up, the present application has at least the following beneficial technical effects: starting the adjustment unit drives the adjustment plate to rise and fall along the adjustment frame, and the adjustment frame drives the pressurizing clamp to adjust the angle through the connecting unit, thereby achieving flatness adjustment of the pressurizing clamp, with strong flexibility, so that the chip to be thinned on the pressurizing clamp can contact more smoothly with the grinding disk of the grinder, thereby improving the chip grinding quality and production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 It is a schematic diagram of the overall structure of Example 1 of the present application.
[0022] Figure 2 It is a schematic diagram of the structure of the pressurized clamp used in the first embodiment of the present application.
[0023] Figure numerals: 1. support seat; 2. mounting seat; 3. adjustment frame; 4. adjustment plate; 5. adjustment screw; 6. guide sleeve; 7. guide rail; 8. guide block; 9. support block; 10. connecting rod; 11. connecting block; 12. first ranging frame; 13. second ranging frame; 14. laser transmitter; 15. laser receiver; 16. ranging screw; 17. ranging nut; 18. guide rod; 19. pressurized clamp. DETAILED DESCRIPTION
[0024] The following is combined with Figure 1-2 This application is described in further detail.
[0025] Embodiment 1
[0026] The embodiment of the present application discloses a laser thickness measurement system for chip thinning.
[0027] Reference Figure 1 and Figure 2The laser thickness measurement system for chip thinning includes a support seat 1 and a mounting seat 2. A plurality of adjustment frames 3 are bolted to the support seat 1. In the embodiment of the present application, the number of adjustment frames 3 is set to four. Adjustment plates 4 are respectively slidably connected to the four adjustment frames 3. The pressurizing fixture 19 is connected to the four adjustment plates 4 through a connecting unit. The four adjustment frames 3 are evenly distributed along the outer edge of the pressurizing fixture 19. The four adjustment frames 3 are respectively provided with adjustment units for driving the adjustment plates 4 to rise and fall. The grinder is arranged on the mounting seat 2 and the grinding disc of the grinder corresponds to the chip to be detected on the pressurizing fixture 19. The center line of the chip to be detected coincides with the center line of the grinding disc. Therefore, the adjustment unit is started to drive the adjustment plate 4 to rise and fall along the adjustment frame 3. The adjustment frame 3 drives the pressurizing fixture 19 to move through the connecting unit to achieve the adjustment of the flatness of the pressurizing fixture 19. The flexibility is strong, so that the chip to be thinned on the pressurizing fixture 19 and the grinding disc of the grinder are in contact with each other more smoothly, thereby improving the chip grinding quality and production efficiency.
[0028] Reference Figure 1 and Figure 2 The adjusting unit comprises an adjusting screw rod 5 rotatably connected to the adjusting frame 3, a support block 9 is bolted to the adjusting frame 3, the adjusting screw rod 5 passes through the support block 9 and is rotatably connected to the support block 9, the support block 9 supports and limits the adjusting screw rod 5, reduces the possibility of position deviation of the adjusting screw rod 5, and improves the stability of the adjusting screw rod 5 during rotation. The outer edge of the adjusting screw rod 5 is threadedly connected with an adjusting nut, the adjusting plate 4 is arranged on the adjusting nut, and the adjusting frame 3 is provided with a first driving assembly for driving the adjusting screw rod 5 to rotate. In the embodiment of the present application, the first adjusting assembly comprises a first driving motor installed on the adjusting frame 3, and the adjusting screw rod 5 is arranged at the output end of the first driving motor. The adjusting frame 3 is bolted with a guide rail 7 arranged parallel to the adjusting screw rod 5, and a guide block 8 matching the size of the guide rail 7 is slidably connected to the guide rail 7, the adjusting plate 4 is arranged on the guide block 8, and the guide rail 7 limits the sliding direction of the guide block 8, reduces the possibility of position deviation of the guide block 8 during the sliding process, and improves the position stability of the adjusting plate 4 during the movement process.
[0029] Reference Figure 1 and Figure 2 , several connecting units respectively include connecting rods 10 hinged on the adjusting plate 4, one end of the connecting rod 10 away from the adjusting plate 4 is hinged with a connecting block 11, a pressurizing fixture 19 is fixedly set on the connecting rod 10 and four connecting rods 10 are evenly distributed on the top of the pressurizing fixture 19.
[0030] Therefore, start the first drive motor, and the first drive motor drives the adjusting screw 5 at the output end to rotate. The rotation of the adjusting screw 5 drives the adjusting nut to move along the length direction of the adjusting screw 5, thereby realizing the lifting and lowering of the adjusting plate 4 on the adjusting frame 3. During the lifting and lowering process of the adjusting plate 4, the connecting rod 10 is driven to lift and lower synchronously, so as to realize the adjustment of the position and equality of the pressurizing fixture 19, with strong flexibility, so that the chip to be thinned on the pressurizing fixture 19 can contact with the grinding disk of the grinder more smoothly, thereby improving the chip grinding quality and production efficiency.
[0031] Reference Figure 1 and Figure 2 A first ranging frame 12 and a second ranging frame 13 which are arranged opposite to each other are bolted to the mounting seat 2, a laser transmitter 14 is slidably connected to the first ranging frame 12, and a laser receiver 15 is slidably connected to the second ranging frame 13, the transmitting end of the laser transmitter 14 corresponds to the receiving end of the laser receiver 15, and the chip to be thinned on the pressurizing fixture 19 is located between the transmitting end of the laser transmitter 14 and the receiving end of the laser receiver 15, the first ranging frame 12 is provided with a first sliding unit for driving the laser transmitter 14 to slide, and the second ranging frame 13 is provided with a second sliding unit for driving the laser receiver 15 to slide.
[0032] Reference Figure 1 and Figure 2 The first sliding unit includes a distance measuring screw 16 rotatably connected to the first distance measuring frame 12, and the outer edge of the distance measuring screw 16 is threadedly connected to a distance measuring nut 17 matching the size of the distance measuring screw 16, and the laser emitter 14 is arranged on the distance measuring nut 17. The first distance measuring frame 12 is provided with a second driving assembly for driving the distance measuring screw 16 to rotate. In the embodiment of the present application, the second driving assembly includes a second driving motor bolted to the first distance measuring frame 12, and the distance measuring screw 16 is arranged at the output end of the second driving motor. The second sliding unit is arranged with reference to the structure of the first sliding unit and the structure of the second sliding unit is the same as that of the first sliding unit. A guide rod 18 arranged parallel to the distance measuring screw 16 is installed on the first distance measuring frame 12, and the outer edge of the guide rod 18 is slidably connected to a guide sleeve 6 matching the size of the guide rod 18. The laser emitter 14 is arranged on the guide sleeve 6, and the guide rail 7 plays a limiting role on the guide sleeve 6, reducing the possibility of positional deviation of the laser emitter 14 during sliding, and improving the stability of the laser emitter 14 during lifting and lowering.
[0033] Therefore, the second drive motor is started to drive the ranging screw 16 at the output end of the second drive motor to rotate, and the ranging nut 17 moves along the length direction of the ranging screw 16 to realize the lifting and lowering of the laser transmitter 14, and the second sliding unit is started to realize the lifting and lowering of the laser receiver 15, so that the transmitting end of the laser transmitter 14 and the receiving end of the laser receiver 15 correspond to the position of the chip thinning, which is convenient for real-time observation of the chip thickness during the subsequent chip thinning process.
[0034] Reference Figure 1 and Figure 2 , a photosensitive diode is arranged on the laser receiver 15, and the laser receiver 15 is pre-set with a set value according to the thickness of the chip to be thinned; when the height at which the laser receiver 15 receives the laser is lower than the set value, the photosensitive diode is in a bright field, and the grinder grinds normally at this time; when the height at which the laser receiver 15 receives the laser reaches the set value, the photosensitive diode becomes a dark field, and the current becomes a weak current, thereby controlling the on-off of the circuit and stopping the grinder from grinding. In the embodiment of the present application, the laser receiver 15 can be connected to a digital display converter, and the laser receiver 15 converts the received laser position into chip thickness in real time through the digital display converter and displays it.
[0035] Therefore, the grinder is started, and the grinding disc of the grinder is driven to grind the chip to be thinned on the press fixture 19; the laser transmitter 14 is aimed at the chip grinding position to emit a laser beam, and when the press fixture 19 covers a certain width of the laser, the remaining laser of the laser transmitter 14 will irradiate the laser receiver 15, and the laser receiver 15 transmits the electrical signal to the digital display converter through signal conversion, and the digital display converter will display the current real-time chip thickness. When the reading of the digital display converter reaches the set thickness, that is, when the height of the laser receiver 15 receiving the laser reaches the set value, the photodiode forms a dark field, and the switch control sensor is automatically disconnected, thereby realizing the automatic stop of the equipment motor, and the chip on the press fixture 19 is thinned to the required thickness.
[0036] In addition, the traditional grinding method in the related art cannot measure the thickness of the chip in time during the chip grinding process, and completely relies on the operator's personal experience in controlling the pressure and grinding time to judge the thinning thickness. There is a situation where the chip is over-thinned, especially when the thickness of the chip is about to reach the required thickness. Once the grinding cannot be stopped in time, it is easy to cause the chip to be scrapped, resulting in low chip production efficiency. Compared with the traditional grinding thickness monitoring method, the present application is more real-time. When the chip thickness measured by laser ranging reaches the set value, the grinder stops working. The entire process simplifies the steps of thickness testing and reduces the risk of chip scratches caused by human behavior of continuously removing the chip due to measuring the thickness. At the same time, from the beginning of chip grinding to the end of final grinding, there is no need for personnel monitoring. It is only necessary to finally remove the chip, which effectively simplifies the steps of the entire process, making it safer, more accurate, and reliable, and saving labor costs.
[0037] The implementation principle of the embodiment of the present application is as follows: the first drive motor is started, and the first drive motor drives the adjusting screw 5 at the output end to rotate, and the adjusting screw 5 rotates to drive the adjusting nut to move along the direction of the adjusting screw 5, thereby realizing the lifting and lowering of the adjusting plate 4 on the adjusting frame 3, and the connecting rod 10 is driven to lift and lower synchronously during the lifting and lowering process of the adjusting plate 4, so as to realize the adjustment of the position and equality of the pressurizing fixture 19, and the flexibility is strong, so that the contact between the chip to be thinned on the pressurizing fixture 19 and the grinding disc of the grinder is smoother, thereby improving the chip grinding quality and production efficiency;
[0038] The second drive motor is started to drive the ranging screw 16 at the output end of the second drive motor to rotate, and the ranging nut 17 moves along the length direction of the ranging screw 16 to realize the lifting and lowering of the laser transmitter 14, and the second sliding unit is started to realize the lifting and lowering of the laser receiver 15, so that the transmitting end of the laser transmitter 14 and the receiving end of the laser receiver 15 correspond to the position of the chip thinning part, which is convenient for real-time observation of the chip thickness in the subsequent chip thinning process;
[0039] After the chip to be thinned on the pressurizing fixture 19, the laser transmitter 14 and the laser receiver 15 are adjusted to the appropriate positions, the grinder is started to grind the chip to be thinned. During the grinding process of the grinding disc, the laser transmitter 14 emits a laser beam at the grinding position of the chip. When the pressurizing fixture 19 blocks a certain width of the laser, the remaining laser of the laser transmitter 14 will irradiate the laser receiver 15. The laser position and laser amount received by the laser receiver 15 change continuously as the thickness of the chip continues to thin. When the height at which the laser receiver 15 receives the laser reaches the set value, the photodiode forms a dark field and the current becomes a weak current, causing the grinder to stop grinding and the operator to take out the thinned chip.
[0040] Embodiment 2
[0041] The present application also discloses a thickness measurement method of a laser thickness measurement system for chip thinning, the thickness measurement method comprising:
[0042] S10, start the first driving assembly, the first driving assembly drives the adjusting screw 5 to rotate, and the adjusting nut moves along the length direction of the adjusting screw 5, so that the adjusting plate 4 and the connecting rod 10 are lifted and lowered along the adjusting frame 3, and the angle of the pressurizing fixture 19 is finely adjusted to a suitable position;
[0043] S20, start the second driving assembly, the second driving assembly drives the ranging screw 16 to rotate, the ranging nut 17 moves along the length direction of the ranging screw 16, and the laser transmitter 14 on the first ranging frame 12 is adjusted to a set position;
[0044] S30, start the second sliding unit to adjust the laser receiver 15 on the second rangefinder 13 to a set position; it should be noted that the second sliding unit can be started synchronously with the first drive assembly and the second drive assembly;
[0045] S40, starting the grinder to drive the grinding disc of the grinder to grind the chip to be thinned on the press fixture 19;
[0046] S50, starting the laser transmitter 14, the laser transmitter 14 is aimed at the chip grinding position to emit laser, and the laser receiver 15 receives the laser in real time;
[0047] S60, when the height at which the laser receiver 15 receives the laser is lower than the set value, the photodiode is in bright field, and the grinder grinds normally; when the height at which the laser receiver 15 receives the laser reaches the set value, the photodiode becomes dark field, and the grinder stops grinding.
[0048] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by the patent law.
Claims
1. A laser thickness measurement system for chip thinning, characterized in that: The invention comprises a support seat (1) and a mounting seat (2); the support seat (1) is provided with a plurality of adjustment frames (3); the plurality of adjustment frames (3) are respectively slidably connected with adjustment plates (4); a pressurizing fixture (19) is connected to the plurality of adjustment plates (4) via a connecting unit; the adjustment frame (3) is provided with an adjustment unit for driving the adjustment plates (4) to rise and fall; a grinder is arranged on the mounting seat (2) and a grinding disc of the grinder corresponds to the pressurizing fixture (19).
2. The laser thickness measurement system for chip thinning according to claim 1, characterized in that: The adjustment unit comprises an adjustment screw (5) rotatably connected to an adjustment frame (3); an outer edge of the adjustment screw (5) is threadedly connected to an adjustment nut; the adjustment plate (4) is arranged on the adjustment nut; and a first driving component for driving the adjustment screw (5) to rotate is provided on the adjustment frame (3).
3. The laser thickness measurement system for chip thinning according to claim 2, characterized in that: The adjusting frame (3) is provided with a guide rail (7) arranged parallel to the adjusting screw rod (5), the guide rail (7) is slidably connected with a guide block (8) matching the guide rail (7), and the adjusting plate (4) is arranged on the guide block (8).
4. The laser thickness measurement system for chip thinning according to claim 2, characterized in that: The adjusting frame (3) is provided with a supporting block (9), and the adjusting screw rod (5) passes through the supporting block (9) and is rotatably connected to the supporting block (9).
5. The laser thickness measurement system for chip thinning according to claim 1, characterized in that: The plurality of connection units respectively comprise connecting rods (10) hinged on the adjustment plate (4), one end of the connecting rod (10) away from the adjustment plate (4) being hinged with a connecting block (11), and the pressure clamps (19) are arranged on the plurality of connecting blocks (11).
6. The laser thickness measurement system for chip thinning according to claim 1, characterized in that: The mounting seat (2) is provided with a first distance measuring frame (12) and a second distance measuring frame (13); the first distance measuring frame (12) is slidably connected to a laser transmitter (14); the second distance measuring frame (13) is slidably connected to a laser receiver (15); the transmitting end of the laser transmitter (14) corresponds to the receiving end of the laser receiver (15); the chip to be thinned on the pressurizing fixture (19) is located between the transmitting end of the laser transmitter (14) and the receiving end of the laser receiver (15); the first distance measuring frame (12) is provided with a first sliding unit for driving the laser transmitter (14) to slide; and the second distance measuring frame (13) is provided with a second sliding unit for driving the laser receiver (15) to slide.
7. The laser thickness measurement system for chip thinning according to claim 6, characterized in that: The laser receiver (15) is provided with a photosensitive diode; when the height at which the laser receiver (15) receives the laser is lower than a set value, the photosensitive diode is in a bright field, and the grinder grinds normally; when the height at which the laser receiver (15) receives the laser reaches a set value, the photosensitive diode becomes a dark field, and the grinder stops grinding.
8. The laser thickness measurement system for chip thinning according to claim 6, characterized in that: The first sliding unit comprises a distance measuring screw (16) rotatably connected to a first distance measuring frame (12); an outer edge of the distance measuring screw (16) is threadedly connected to a distance measuring nut (17) matching the distance measuring screw (16); the laser transmitter (14) is arranged on the distance measuring nut (17); and a second driving component for driving the distance measuring screw (16) to rotate is provided on the first distance measuring frame (12).
9. The laser thickness measurement system for chip thinning according to claim 8, characterized in that: The first distance measuring frame (12) is provided with a guide rod (18) arranged parallel to the distance measuring screw rod (16); the outer edge of the guide rod (18) is slidably connected to a guide sleeve (6) matching the guide rod (18); and the laser emitter (14) is arranged on the guide sleeve (6).
10. A thickness measurement method based on the laser thickness measurement system for chip thinning according to claim 7, characterized in that: The thickness measurement method comprises: The adjusting unit is started, and the adjusting plate (4) drives the pressurizing fixture (19) to adjust to a set position; Starting the first sliding unit to adjust the laser transmitter (14) on the first distance measuring frame (12) to a set position; Starting the second sliding unit and adjusting the laser receiver (15) on the second distance measuring frame (13) to a set position; Starting the grinder to drive the grinding disc of the grinder to grind the chip to be thinned on the pressurizing fixture (19); The laser transmitter (14) is started, and the laser transmitter (14) is aimed at the chip grinding position to emit laser light, and the laser receiver (15) receives the laser light in real time; when the height at which the laser receiver (15) receives the laser light is lower than a set value, the photosensitive diode is in a bright field, and the grinder grinds normally at this time; when the height at which the laser receiver (15) receives the laser light reaches a set value, the photosensitive diode becomes a dark field, and the grinder stops grinding at this time.