Wafer chip jacking structure

Abstract

The invention relates to the technical field of wafer jacking, in particular to a wafer chip jacking structure which comprises a base, a jacking pipe is fixed to the top face of the base, a jacking table is vertically and slidably connected into the jacking pipe, an electric cylinder is fixed between the bottom of the jacking table and the base, the wafer chip jacking structure further comprises multiple ejector pins, and each ejector pin comprises a U-shaped part and a vertical part; the vertical part is fixed to one end of the U-shaped part, the U-shaped part is rotationally connected to the ejecting table, a motor is fixed to the ejecting table, and the motor is fixedly connected with a rotating shaft of the U-shaped part. According to the blue film ejecting device, the balls are arranged at the ends of the ejector pins and make rolling contact with a blue film, blue film vibration caused by sliding friction is reduced, and a liquid storage groove is formed in each ejector pin; and the balls are filled with the lubricating liquid, so that a lubricating liquid layer is formed between the balls and the blue film, the vibration of the blue film caused by the friction effect can be further reduced, and the stability of the wafer chip can be ensured when the position of the wafer chip is adjusted.

Description

Technical Field

[0001] The present invention relates to the field of wafer lifting, and in particular to a wafer chip lifting structure. Background Art

[0002] Wafer chip lifting refers to the separation of the wafer from the temporary support material through precision mechanical mechanisms such as ejector pins, suction cups, support columns, etc. during the semiconductor manufacturing process. It is a key action for semiconductor equipment to achieve wafer transmission, positioning, and processing.

[0003] The invention patent with publication number CN118553680A discloses a wafer chip lifting structure. Through a multi-pin structure, the lifting state is adjusted by micro-movement of the pins under the blue film, thereby ensuring smooth lifting of the chip.

[0004] When lifting thicker chips, the thicker chips have the characteristics of high stiffness, large mass, high natural frequency and strong damping, which can effectively suppress the dynamic response of friction and maintain position stability. However, with the improvement of semiconductor manufacturing technology, wafer materials are becoming thinner and thinner. For thin chips, due to their low stiffness, light mass, low natural frequency and weak damping, when the ejector pin slides on the bottom of the blue film, resonance or self-excited vibration is likely to occur under the friction of the ejector pin, resulting in relative displacement between the chip and the blue film. When the chip is subsequently adsorbed by the suction cup, the positioning accuracy is reduced due to the chip position offset, which in turn affects the quality of the semiconductor finished product. Summary of the Invention

[0005] The purpose of the present invention is to solve the shortcomings of the prior art that there is sliding friction between the ejector pin and the blue film, which is prone to generate dynamic vibration, and to propose a wafer chip lifting structure.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a wafer chip lifting structure, comprising a base, a lifting tube fixed to the top surface of the base, a lifting platform vertically slidably connected to the lifting tube, an electric cylinder fixed between the bottom of the lifting platform and the base, and further comprising:

[0007] Ejectors, wherein the ejectors are provided in plurality, each comprising a U-shaped portion and a vertical portion, wherein the vertical portion is fixed to one end of the U-shaped portion, the U-shaped portion is rotatably connected to an ejection platform, a motor is fixed to the ejection platform, and the motor is fixedly connected to the rotating shaft of the U-shaped portion;

[0008] A contact block, the contact block is fixed to the end of the ejector pin, the end of the contact block is provided with a mounting groove, and a ball is embedded in the mounting groove;

[0009] A liquid reservoir is provided inside the ejector pin, the bottom of the mounting groove is connected to the liquid reservoir, an extrusion piston is inserted into the liquid reservoir at one end of the U-shaped portion, and lubricating liquid is filled between the extrusion piston and the ball.

[0010] Specifically, when the ejector pin slides on the bottom of the blue film to adjust the position of the wafer chip, the blue film may be caused to vibrate under the action of sliding friction, which in turn causes relative displacement between the wafer chip and the blue film, affecting the positioning accuracy of the subsequent wafer chip grabbing by the adsorption device. In order to solve the above problem, the present invention provides a ball at the end of the ejector pin, and the ball is in rolling contact with the blue film, which is conducive to reducing the vibration of the blue film caused by sliding friction. In addition, a liquid reservoir is provided inside the ejector pin and filled with lubricating liquid. A micro gap is provided between the ball and the mounting groove, so that the ball can carry out part of the lubricating liquid during the rolling process, so that a lubricating liquid layer is formed between the ball and the blue film, further reducing the friction between the ball and the blue film, which is conducive to further reducing the vibration of the blue film caused by friction, and thus helping to ensure the stability of the wafer chip when the position of the wafer chip is adjusted;

[0011] It should be noted that the device needs to apply the lubricating liquid upwards, which is an anti-gravity method. The lubricating liquid is difficult to rise automatically. Therefore, the present invention provides a U-shaped portion at the bottom of the ejector pin to form a U-shaped tube, and inserts an extrusion piston inside the U-shaped tube. The liquid inside the U-shaped portion can be automatically squeezed into the vertical portion by relying on the gravity of the extrusion piston to complete the automatic rise of the lubricating liquid, which is beneficial to ensure that the ball can stably contact the lubricating liquid and avoid the occurrence of lubricating liquid supply interruption. It is beneficial to ensure the stability of the lubricating layer, and then ensure the stability of the wafer chip position when adjusting the ejection process. A filling valve is installed in the middle of the extrusion piston. By connecting the filling valve to an external filling device, the lubricating liquid can be replenished into the ejector pin.

[0012] Preferably, a turnover plate is rotatably connected to the inner wall of the jacking tube, a limit bar is provided at the bottom of the turnover plate, the limit bar is fixed to the inner wall of the jacking tube, and the turnover plate is arranged above the ejector pin.

[0013] It should be noted that the ejector pin has three stages in the ejection process. The initial stage is the rising stage, in which the ejector pin moves upward in the lifting tube without contacting the blue film. The middle stage is the lifting stage, in which the ejector pin contacts the blue film and gradually lifts the blue film. The last stage is the resetting stage, in which the ejector pin gradually separates from the blue film and descends to reset. Specifically, in the rising stage of the ejector pin, before the ejector pin contacts the blue film, it first contacts the flip plate, which is supported by the limit bar and is located above the ejector pin. During the rising process of the ejector pin, the flip plate can be pushed to flip the flip plate. In this process, the ball rolls on the surface of the flip plate. During the rolling process, the lubricating fluid inside the mounting groove can be re-applied to the surface of the ball. Therefore, before lifting the blue film, a lubricating layer is formed by pre-applying it on the surface of the ball, which is beneficial to reduce the friction and vibration between the ball and the blue film due to the lack of a uniform and effective lubricating layer during the lifting process. This is beneficial to ensure the stability of the blue film and the wafer chip during the lifting process, thereby ensuring the quality of the wafer chip.

[0014] Preferably, a plurality of micro holes are evenly formed on the surface of the ball.

[0015] Preferably, two contact strips are obliquely provided on the bottom surface of the flip plate, and the contact strips are fixedly connected to the bottom surface of the flip plate. When the ejector pin rises, the ball contacts the end surfaces of the two contact strips.

[0016] Preferably, the mounting groove includes a ball groove, a vertical groove and a bottom groove, the vertical groove is connected between the ball groove and the bottom groove, the bottom groove is connected to the liquid storage tank, the ball is installed inside the ball groove, the notch of the ball groove is fixed with a sealing ring, the bottom of the ball is provided with an elastic support component, the elastic support component is used to elastically push the ball so that the ball is in close contact with the sealing ring, a plurality of guide grooves are opened on the inner wall of the ball groove, and when the ball descends, the guide groove is used to connect the upper and lower spaces of the ball.

[0017] Preferably, the elastic support assembly includes a moving block, which is inserted into the bottom groove, and the top of the moving block is in sealing contact with the bottom of the vertical groove. A trigger rod is fixed to the top of the moving block, and the trigger rod is inserted into the vertical groove, and the top of the trigger rod is in contact with the ball. A pulling assembly is provided on the top surface of the moving block, and the pulling assembly is used to pull the moving block to maintain the blocking state of the moving block on the vertical groove.

[0018] Preferably, the pulling assembly includes an insertion rod, which is fixed to the top of the trigger rod. A slot is provided on the inner wall of the contact block, and the insertion rod is inserted into the slot. A pulling spring is fixed between the insertion rod and the inner wall of the slot.

[0019] Preferably, a blocking ring and a guide tube are fixedly sleeved on the outer side of the trigger rod, the guide tube is arranged above the blocking ring, the side wall of the guide tube has a tapered surface, and a conducting groove is provided on the tapered surface of the guide tube.

[0020] Preferably, an elastic telescopic rod is provided inside the lifting tube, and the elastic telescopic rod is arc-shaped. The fixed end of the elastic telescopic rod is fixed to the inner wall of the lifting tube, and the movable end of the elastic telescopic rod is provided on the flipping path of the flip plate. There is a moving space between the movable end of the elastic telescopic rod and the flip plate. An electromagnet is fixed on the top of the extrusion piston, and the U-shaped section of the thimble is made of ferromagnetic material.

[0021] Preferably, a friction strip is provided between the two contact strips, the surface of the friction strip is provided with a groove adapted to the ball bearing, a friction surface is provided in the groove, the surface of the flip plate is provided with a slide groove, the friction strip is vertically slidably connected inside the slide groove, a first rack is fixed on the top surface of the friction strip, a gear is provided on one side of the first rack, a second rack is provided on one side of the gear, and the gears are meshed with the first rack and the second rack respectively.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The present invention arranges a ball at the end of the ejector pin, and the ball and the blue film are in rolling contact, which is beneficial to reducing the vibration of the blue film caused by sliding friction. In addition, a liquid reservoir is provided inside the ejector pin and filled with lubricating liquid. A micro gap is provided between the ball and the mounting groove, so that the ball can carry out part of the lubricating liquid during the rolling process, so that a lubricating liquid layer is formed between the ball and the blue film, further reducing the friction between the ball and the blue film, which is beneficial to further reducing the vibration of the blue film caused by friction, and further ensuring the stability of the wafer chip when the wafer chip position is adjusted, thereby ensuring the quality of the semiconductor product.

[0024] 2. During the rising stage of the ejector pin, before the ejector pin contacts the blue film, it first contacts the flip plate. The flip plate is supported by the limit bar and is located above the ejector pin. During the rising process of the ejector pin, the flip plate can be pushed to flip the flip plate. During this process, the ball rolls on the surface of the flip plate. During the rolling process, the lubricating fluid inside the mounting groove can be re-applied to the surface of the ball. Therefore, before lifting the blue film, a lubricating layer is formed by pre-applying it on the surface of the ball. This helps to reduce the friction and vibration between the ball and the blue film due to the lack of a uniform and effective lubricating layer during the lifting process, which helps to ensure the stability of the blue film and the wafer chip during the lifting process, thereby ensuring the quality of the wafer chip.

[0025] 3. The present invention sets the friction strip to a sliding state and extends its length, so that when lifting wafer chips of various sizes, the ball can contact the friction strip when the ejector pin rises until the second rack contacts the elastic telescopic rod. Under the elastic resistance of the elastic telescopic rod, the second rack will be pushed to move downward, thereby causing the gear to rotate, driving the first rack to move upward, and pulling the friction strip away from the ball through the first rack, so that only the contact strip is in contact with the ball until the ball is separated from the flip plate. This embodiment improves the friction strip and cooperates with the elastic telescopic rod, so that no matter what position the ball rises from, it can first contact the friction strip to ensure a stable rolling effect. When contacting the elastic telescopic rod, the friction strip can actively separate from the ball to avoid adverse effects on the subsequent pre-coating of the lubricating liquid on the end face area of the ball. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0027] Figure 2 It is a schematic diagram of the overall cross-sectional structure of the present invention.

[0028] Figure 3 For the present invention Figure 2 A in the figure is an enlarged structural diagram.

[0029] Figure 4 It is a schematic diagram of the cross-sectional structure of the ejector pin of the present invention.

[0030] Figure 5 It is a schematic diagram of the cross-sectional structure of the contact block of the present invention.

[0031] Figure 6 It is a structural schematic diagram of the moving block, trigger rod, blocking ring and guide tube of the present invention.

[0032] Figure 7 It is a schematic diagram of the cross-sectional structure of the flip plate of the present invention.

[0033] Figure 8 It is a schematic diagram of the flip plate structure of the present invention.

[0034] In the figure: 1. base; 2. lifting tube; 3. jacking table; 4. electric cylinder; 5. ejector pin; 6. U-shaped part; 7. vertical part; 8. motor; 9. contact block; 10. mounting groove; 11. ball; 12. liquid storage tank; 13. extrusion piston; 14. flip plate; 15. limit strip; 16. micro hole; 17. contact strip; 18. ball groove; 19. vertical groove; 20. bottom groove; 21. sealing ring; 22. guide groove; 23. moving block; 24. trigger rod; 25. plug rod; 26. slot; 27. pulling spring; 28. sealing ring; 29. guide cylinder; 30. conical surface; 31. conduction groove; 32. elastic telescopic rod; 33. electromagnet; 34. friction strip; 35. groove; 36. slide groove; 37. first rack; 38. gear; 39. second rack. DETAILED DESCRIPTION

[0035] The following description is intended to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are merely examples, and those skilled in the art may conceive of other obvious variations.

[0036] like Figures 1 to 8 The wafer chip lifting structure shown in the figure includes a base 1, a lifting tube 2 is fixed on the top surface of the base 1, a lifting platform 3 is vertically slidably connected inside the lifting tube 2, and an electric cylinder 4 is fixed between the bottom of the lifting platform 3 and the base 1, and also includes:

[0037] Ejector pin 5, there are multiple ejector pins 5, each including a U-shaped portion 6 and a vertical portion 7, the vertical portion 7 is fixed to one end of the U-shaped portion 6, the U-shaped portion 6 is rotatably connected to the ejection platform 3, a motor 8 is fixed to the ejection platform 3, and the motor 8 is fixedly connected to the rotating shaft of the U-shaped portion 6;

[0038] The contact block 9 is fixed to the end of the ejector pin 5. The end of the contact block 9 is provided with a mounting groove 10, and a ball 11 is embedded in the mounting groove 10;

[0039] The liquid reservoir 12 is opened inside the ejector pin 5, and the bottom of the mounting groove 10 is connected to the liquid reservoir 12. The liquid reservoir 12 is located at one side of the end of the U-shaped portion 6 and an extrusion piston 13 is inserted therein. The space between the extrusion piston 13 and the ball 11 is filled with lubricating liquid.

[0040] Specifically, when in use, the base 1 is installed on the lifting machine tool, and the wafer chip is adsorbed by the adsorption platform of the lifting machine tool and is located above the lifting tube 2. This is the existing technology and will not be described in detail here. By starting the electric cylinder 4, the lifting platform 3 can be pushed to move upward, and the ejector pin 5 moves upward with the lifting platform 3 and contacts the blue film at the bottom of the wafer chip. Under the action of the lifting, the blue film is stretched and deformed upward, gradually separated from the wafer chip, and then the wafer chip is adsorbed and transported through an external adsorption device, thereby completing the separation of the wafer chip and the blue film;

[0041] During the lifting process, the skew state of the wafer chip can be detected in real time by the detection device on the lifting machine. Specifically, the existing laser triangulation measurement technology can be used to emit laser to the chip surface, and the sensor can be used to capture the reflected light. The height difference of the chip surface is calculated according to the position change of the reflected light, so as to obtain the chip tilt angle. When the wafer chip is detected to be skewed, the U-shaped part 6 of the corresponding ejector 5 can be driven to rotate around the rotation axis by starting the motor 8, so as to adjust the height of the end of each ejector 5, so that the wafer chip can be restored to a flat state. This is the existing technology and I will not elaborate on it here. The difference from the existing technology is that in the process of the ejector 5 sliding on the bottom of the blue film to adjust the position of the wafer chip, the sliding friction may cause the blue film to vibrate, and then This causes relative displacement between the wafer chip and the blue film, affecting the positioning accuracy of the subsequent grasping of the wafer chip by the adsorption device. In order to solve the above problem, the present invention provides a ball 11 at the end of the ejector pin 5. The ball 11 is in rolling contact with the blue film, which is conducive to reducing the vibration of the blue film caused by sliding friction. A liquid reservoir 12 is provided inside the ejector pin 5 and filled with lubricating liquid. There is a micro gap between the ball 11 and the mounting groove 10, so that the ball 11 can carry out part of the lubricating liquid during the rolling process, so that a lubricating liquid layer is formed between the ball 11 and the blue film, further reducing the friction between the ball 11 and the blue film, which is conducive to further reducing the vibration of the blue film caused by friction, and thus helping to ensure the stability of the wafer chip when the position of the wafer chip is adjusted;

[0042] It should be noted that, unlike the conventional application of lubricating liquid, this device needs to apply the lubricating liquid upwards, which is an anti-gravity method, and the lubricating liquid is difficult to rise automatically. Therefore, the present invention provides a U-shaped portion 6 at the bottom of the ejector pin 5 to form a U-shaped tube, and inserts an extrusion piston 13 inside it. The liquid inside the U-shaped portion 6 can be automatically squeezed into the vertical portion 7 by relying on the gravity of the extrusion piston 13, thereby completing the automatic rise of the lubricating liquid, which is beneficial to ensure that the ball 11 can stably contact the lubricating liquid, avoid the occurrence of lubricating liquid supply interruption, and is beneficial to ensure the stability of the lubricating layer, thereby ensuring the stability of the ejector pin 5 during the adjustment of the wafer chip position, and a filling valve is installed in the middle of the extrusion piston 13. By connecting the filling valve to an external filling device, the lubricating liquid can be replenished into the ejector pin 5.

[0043] As a further embodiment of the present invention, a flip plate 14 is rotatably connected to the inner wall of the jacking pipe 2, and a limiting strip 15 is provided at the bottom of the flip plate 14. The limiting strip 15 is fixed on the inner wall of the jacking pipe 2, and the flip plate 14 is arranged above the thimble 5.

[0044] It should be noted that the ejector pin 5 has three stages in the ejection process. The initial stage is the ascending stage, in which the ejector pin 5 moves upward in the lifting tube 2 without contacting the blue film. The middle stage is the lifting stage, in which the ejector pin 5 contacts the blue film and gradually lifts the blue film. The last stage is the resetting stage, in which the ejector pin 5 gradually separates from the blue film and descends to reset.

[0045] Specifically, since the lubricating liquid is applied to the back side of the blue film, the lubricating oil on the surface of the ball 11 always tends to flow downward under the action of gravity. During the reset stage and the rising stage, part of the lubricating liquid on the surface of the ball 11 may flow downward and detach from the surface of the ball 11 under the action of gravity, resulting in difficulty in forming a uniform and effective lubricating layer between the ball 11 and the blue film during the lifting stage. The present invention can solve the above problem. The specific working method is as follows: during the rising stage of the ejector pin 5, before the ejector pin 5 contacts the blue film, it first contacts the flip plate 14. The flip plate 14 is supported by the limit bar 15 and is located above the ejector pin 5. During the rising process of the ejector pin 5, the flip plate 14 can be pushed to flip the flip plate 14. During this process, the ball 11 rolls on the surface of the flip plate 14. During the rolling process, the lubricating liquid inside the mounting groove 10 can be re-applied to the surface of the ball 11, so that before the blue film is lifted, a lubricating layer is formed by pre-applying it on the surface of the ball 11, which is beneficial to reduce the friction and vibration between the ball 11 and the blue film due to the lack of a uniform and effective lubricating layer during the lifting process, which is beneficial to ensure the stability of the blue film and the wafer chip during the lifting process, thereby ensuring the quality of the wafer chip.

[0046] As a further embodiment of the present invention, a plurality of micro holes 16 are evenly formed on the surface of the ball 11 .

[0047] Specifically, in order to further reduce the influence of gravity on the uniformity of the lubricating fluid, this embodiment opens micropores 16 on the surface of the ball 11. When the lubricating fluid is applied to the surface of the ball 11, the micropore 16 structure effectively improves the adhesion ability of the liquid on the solid surface by increasing the actual contact area between the ball 11 and the lubricating fluid. According to the surface tension theory, the van der Waals force and capillary force between the inner wall of the pore and the lubricating fluid molecules form a composite constraint force, which can counteract the downward flow trend of the liquid caused by gravity, thereby reducing the phenomenon of the lubricating fluid leaving the surface of the ball 11 due to gravity. This structural design optimizes the interface effect at the microscale, thereby achieving stable adhesion of the lubricating fluid to the surface of the ball 11, thereby further reducing the adverse effect of gravity on the uniformity of the lubricating fluid on the surface of the ball 11.

[0048] As a further embodiment of the present invention, two contact strips 17 are obliquely provided on the bottom surface of the flip plate 14 , and the contact strips 17 are fixedly connected to the bottom surface of the flip plate 14 . When the ejector pin 5 rises, the ball 11 contacts the end surfaces of the two contact strips 17 .

[0049] Specifically, in the process of pre-applying lubricating liquid on the surface of the ball 11, if the traditional method of directly contacting the top surface of the ball 11 with the flip plate 14 is adopted, when the ball 11 detaches from the flip plate 14, the contact area between the flip plate 14 and the top surface of the ball 11 will be affected by the interface adhesion force, resulting in part of the lubricating liquid being carried away from the surface of the ball 11. The uneven peeling of the lubricating liquid on the top surface of the ball 11 will cause insufficient local oil film thickness, destroy the preset lubrication uniformity, and affect the lubrication effect when it subsequently contacts the blue film. In order to solve the above problems, the present invention provides a contact strip 17 on the surface of the flip plate 14. When the ball 11 rises, it directly contacts the contact strip 17. The contact position is far away from the top surface area of the ball 11 that subsequently contacts the blue film, which is beneficial to ensure the lubrication effect of the contact area when the ball 11 subsequently contacts the blue film.

[0050] As a further embodiment of the present invention, the mounting groove 10 includes a ball groove 18, a vertical groove 19 and a bottom groove 20. The vertical groove 19 is connected between the ball groove 18 and the bottom groove 20. The bottom groove 20 is connected to the liquid storage tank 12. The ball 11 is installed inside the ball groove 18. A sealing ring 21 is fixed to the groove of the ball groove 18. An elastic support component is provided at the bottom of the ball 11. The elastic support component is used to elastically push the ball 11 so that the ball 11 is in close contact with the sealing ring 21. A plurality of guide grooves 22 are provided on the inner wall of the ball groove 18. When the ball 11 descends, the guide groove 22 is used to connect the upper and lower spaces of the ball 11.

[0051] Specifically, when not being lifted, the liquid reservoir 12 is always connected to the outside world, which may cause the lubricating liquid inside to dry out or even condense. As a result, during the process of pre-coating the lubricating layer, the lubricating liquid in the liquid reservoir 12 is difficult to be adhered to by the ball 11. To solve the above problem, the present invention provides a sealing ring 21 at the notch position of the vertical groove 19, and uses an elastic support component to push the ball 11 upward so that the ball 11 contacts the sealing ring 21, thereby reducing the contact opportunity between the lubricating liquid in the ball groove 18 and the outside world, and delaying the occurrence of drying and condensation.

[0052] When the ball 11 contacts the blue film, under the blocking effect of the blue film, the ball 11 first moves into the ball groove 18 and breaks away from the sealing ring 21, so that the slot of the vertical groove 19 is opened, and through multiple guide grooves 22, the upper and lower spaces of the ball 11 can be connected, so that the lubricating liquid in the liquid storage tank 12 can enter the bottom of the ball 11 through the bottom groove 20 and the vertical groove 19, and then enter the space above the ball 11 along the guide groove 22, so that the upper and lower parts of the ball 11 are filled with lubricating liquid, thereby ensuring that the lubricating liquid can be evenly applied to the surface of the ball 11 when the ball 11 rolls, forming a lubricating layer on the surface of the ball 11, which is beneficial to reduce the adverse effects of the drying of the lubricating liquid on the pre-application and subsequent jacking process.

[0053] As a further embodiment of the present invention, the elastic support assembly includes a moving block 23, which is inserted into the bottom groove 20, and the top of the moving block 23 is in sealing contact with the bottom of the vertical groove 19. A trigger rod 24 is fixed to the top of the moving block 23, and the trigger rod 24 is inserted into the vertical groove 19. The top of the trigger rod 24 is in contact with the ball 11. A pulling assembly is provided on the top surface of the moving block 23, and the pulling assembly is used to pull the moving block 23 to maintain the blocking state of the moving block 23 on the vertical groove 19.

[0054] The pulling assembly includes an insertion rod 25, which is fixed to the top of the trigger rod 24. A slot 26 is provided on the inner wall of the contact block 9, and the insertion rod 25 is inserted into the slot 26. A pulling spring 27 is fixed between the insertion rod 25 and the inner wall of the slot 26.

[0055] Specifically, since the ball 11 has a microporous structure and poor sealing performance, it can only delay the drying and condensation of the lubricating liquid. In order to further reduce the chance of the lubricating liquid coming into contact with the outside world, the present invention provides a movable block 23 in the bottom groove 20. When not lifting, the spring 27 pulls the insertion rod 25 and the movable block 23, so that the movable block 23 is closely attached to the vertical groove 19, thereby blocking the vertical groove 19 and blocking the communication between the ball groove 18 and the liquid reservoir 12. This further prevents the lubricating liquid in the liquid reservoir 12 from long-term contact with the outside world, which may lead to drying and condensation.

[0056] During the lifting process, the ball 11 first contacts the bottom of the blue film. Under the resistance of the blue film, the ball 11 first moves into the ball groove 18, and pushes the trigger rod 24 and the moving block 23 to move downward. The moving block 23 is pushed by the lubricating fluid to squeeze the piston 13 in the opposite direction for an end distance, so that the moving block 23 can be separated from the bottom of the vertical groove 19, exposing the notch of the vertical groove 19. Under the action of gravity, the squeezing piston 13 pushes the liquid in the liquid storage tank 12 into the vertical groove 19 and enters the ball groove 18 through the vertical groove 19, thereby ensuring that the lubricating fluid can be evenly applied to the surface of the ball 11 when the ball 11 rolls, forming a lubricating layer on the surface of the ball 11, which is beneficial to reduce the adverse effects of the drying of the lubricating fluid on the pre-coating and subsequent lifting processes.

[0057] As a further implementation scheme of the present invention, a sealing ring 28 and a guide tube 29 are fixedly mounted on the outer side of the trigger rod 24. The guide tube 29 is arranged above the sealing ring 28. The side wall of the guide tube 29 has a conical surface 30, and a conducting groove 31 is provided on the conical surface 30 of the guide tube 29.

[0058] Specifically, when relative displacement occurs between the ball 11 and the blue film, the ball 11 is in a rotating state. If the bottom of the ball 11 is always in frictional contact with the trigger rod 24, the ball 11 may vibrate, resulting in unstable lifting. In order to solve the above problem, the present invention provides a guide tube 29 on the outside of the trigger rod 24. When the ball 11 presses the trigger rod 24, the guide tube 29 and the blocking ring 28 move downward synchronously to expose the conducting groove 31. When the ball 11 is pressed to the bottom, the blocking ring 28 is separated from the vertical groove 19, and the guide tube 29 is in a state of contact with the trigger rod 24. Located inside the vertical groove 19, under the action of hydraulic pressure, the lubricating liquid can only enter the vertical groove 19 through the guide groove 31. Since the internal size of the guide groove 31 is small and the hydraulic action is large, under the guidance of the conical surface 30 and the hydraulic push, the guide cylinder 29 will move downward again, so that a gap is generated between the guide cylinder 29 and the vertical groove 19, thereby increasing the passage path of the lubricating liquid. When the guide cylinder 29 descends, it will break away from the bottom of the ball 11, thereby avoiding friction contact with the ball 11 during the jacking process, resulting in unstable jacking.

[0059] As a further implementation scheme of the present invention, an elastic telescopic rod 32 is provided inside the jacking tube 2. The elastic telescopic rod 32 is arc-shaped, and the elastically telescopic fixed end is fixed to the inner wall of the jacking tube 2. The movable end of the elastic telescopic rod 32 is provided on the flipping path of the flip plate 14. There is a moving space between the movable end of the elastic telescopic rod 32 and the flip plate 14. An electromagnet 33 is fixed on the top of the extrusion piston 13, and the U-shaped section of the thimble 5 is made of ferromagnetic material.

[0060] Specifically, some processing steps require preheating of the wafer. When the temperature is high, the effective components in the lubricating fluid may evaporate quickly and become ineffective. After each lifting, some lubricating fluid will remain on the surface of the ball 11. In order to reduce the impact of the used lubricating fluid on the next lifting, the present invention starts the electromagnet 33 before pre-coating the lubricating fluid on the surface of the ball 11 to position the extrusion piston 13. Therefore, when the ball 11 contacts the flip plate 14, it will not move into the vertical groove 19. At this time, the ball 11 contacts the sealing ring 21 under the support of the elastic support component. In the process of pushing the flip plate 14, the ball 11 rotates on the surface of the flip plate 14, so that the sealing ring 21 scrapes off the residual lubricating fluid on the surface of the ball 11, thereby avoiding the residual ineffective lubricating fluid from causing adverse effects on the next lifting. On the other hand, by limiting the descent of the ball 11, it can also be avoided that a large amount of residual lubricating fluid is brought into the ball groove 18 during the rotation of the ball 11, thereby contaminating the lubricating fluid in the ball groove 18.

[0061] Furthermore, in the rear section where the lubricant is pre-applied to the surface of the ball 11, the flip plate 14 flips upward and contacts the elastic telescopic rod 32, compressing the elastic telescopic rod 32. A pressure sensor is installed inside the elastic telescopic rod 32. When the elastic telescopic rod 32 contracts, the spring inside the elastic telescopic rod 32 pushes the pressure sensor, causing the pressure value detected by the pressure sensor to increase, thereby controlling the electromagnet 33 to cancel the positioning of the extrusion piston 13. Under the gravity of the flip plate 14 and the extrusion of the elastic telescopic rod 32, the ball 11 will enter the ball groove 18 and complete the subsequent smearing function.

[0062] As a further embodiment of the present invention, a friction strip 34 is provided between the two contact strips 17, and a groove 35 adapted to the ball 11 is provided on the surface of the friction strip 34, and a friction surface is provided in the groove 35. A slide groove 36 is provided on the surface of the flip plate 14, and the friction strip 34 is vertically slidably connected inside the slide groove 36. A first rack 37 is fixed on the top surface of the friction strip 34, and a gear 38 is provided on one side of the first rack 37, and a second rack 39 is provided on one side of the gear 38. The gears 38 are meshed with the first rack 37 and the second rack 39.

[0063] Specifically, as can be seen from the above embodiment, in the initial stage of contact between the ball 11 and the flip plate 14, the ball 11 does not descend, and a large amount of residual impurities can be scraped off by the rotation of the ball 11 and the sealing ring 21. During this process, it is necessary to ensure that the ball 11 is in a rotating state. Therefore, in order to increase the friction between the ball 11 and the flip plate 14, the present invention provides a friction strip 34 on the flip plate 14. The friction strip 34 has a groove 35. The ball 11 contacts the friction surface in the groove 35, thereby ensuring that the ball 11 can rotate stably during the movement process, thereby ensuring the scraping effect.

[0064] In conventional methods, it is only necessary to set a friction strip 34 at the front section of the flip plate 14 and a contact strip 17 at the rear end of the flip plate 14. This ensures the initial scraping effect and ensures that the lubricant is evenly distributed in the top area of the ball 11 when the lubricant is subsequently applied to the surface of the ball 11.

[0065] However, due to the different sizes of wafer chips, in the prior art, the flipping of the ejector pins 5 can be controlled to adjust the spacing between the ejector pins 5, and then the contact position between the ejector pins 5 and the wafer chips can be adjusted, so as to better adapt to wafers of different sizes. After the position of the ejector pins 5 changes, the initial contact position of the ejector pins 5 and the flip plate 14 will also change. When the wafer chip size is small, the ejector pins 5 gather together. The conventional setting method may cause the ejector pins 5 to directly contact the contact strips 17 during the rising process, resulting in failure of the friction strips 34. In order to solve the above problem, the present invention sets the friction strips 34 to a sliding state and extends its length. When wafer chips of various sizes are lifted, the ball 11 can contact the friction strips 34 when the ejector pins 5 rise, until When the second rack 39 contacts the elastic telescopic rod 32, the elastic resistance of the elastic telescopic rod 32 will push the second rack 39 to move downward, thereby causing the gear 38 to rotate, driving the first rack 37 to move upward, and pulling the friction strip 34 away from the ball 11 through the first rack 37, so that only the contact strip 17 contacts the ball 11 until the ball 11 is separated from the flip plate 14. This embodiment improves the friction strip 34 and cooperates with the elastic telescopic rod 32, so that no matter what position the ball 11 rises in, it can first contact the friction strip 34 to ensure a stable rolling effect. When contacting the elastic telescopic rod 32, the friction strip 34 can actively separate from the ball 11, avoiding adverse effects on the subsequent pre-coating of the lubricating liquid in the end face area of the ball 11.

[0066] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. Various changes and improvements are possible without departing from the spirit and scope of the present invention, and such changes and improvements fall within the scope of the invention as claimed.

Claims

1. A wafer chip lifting structure, comprising a base (1), a lifting tube (2) fixed on the top surface of the base (1), a lifting platform (3) vertically slidably connected inside the lifting tube (2), an electric cylinder (4) fixed between the bottom of the lifting platform (3) and the base (1), characterized in that: Also includes: A plurality of ejector pins (5) are provided. The ejector pins (5) include a U-shaped portion (6) and a vertical portion (7). The vertical portion (7) is fixed to one end of the U-shaped portion (6). The U-shaped portion (6) is rotatably connected to a jacking platform (3). A motor (8) is fixed to the jacking platform (3). The motor (8) is fixedly connected to the rotating shaft of the U-shaped portion (6). A contact block (9), wherein the contact block (9) is fixed to the end of the ejector pin (5), a mounting groove (10) is provided at the end of the contact block (9), and a ball (11) is embedded in the mounting groove (10); A liquid reservoir (12) is provided inside the ejector pin (5), the bottom of the mounting groove (10) is connected to the liquid reservoir (12), an extrusion piston (13) is inserted into the liquid reservoir (12) at one end of the U-shaped portion (6), and a lubricating liquid is filled between the extrusion piston (13) and the ball (11).

2. The wafer chip lifting structure according to claim 1, characterized in that: A flip plate (14) is rotatably connected to the inner wall of the jacking tube (2), a limit bar (15) is provided at the bottom of the flip plate (14), the limit bar (15) is fixed on the inner wall of the jacking tube (2), and the flip plate (14) is provided above the ejector pin (5).

3. The wafer chip lifting structure according to claim 2, characterized in that: A plurality of micro holes (16) are evenly formed on the surface of the ball (11).

4. The wafer chip lifting structure according to claim 2, characterized in that: Two contact strips (17) are obliquely arranged on the bottom surface of the flip plate (14), and the contact strips (17) are fixedly connected to the bottom surface of the flip plate (14). When the ejector pin (5) rises, the ball (11) contacts the end surfaces of the two contact strips (17).

5. The wafer chip lifting structure according to claim 1, characterized in that: The mounting groove (10) comprises a ball groove (18), a vertical groove (19) and a bottom groove (20); the vertical groove (19) is arranged between the ball groove (18) and the bottom groove (20); the bottom groove (20) is communicated with the liquid storage tank (12); the ball (11) is installed inside the ball groove (18); a sealing ring (21) is fixed to the notch of the ball groove (18); an elastic support component is provided at the bottom of the ball (11); the elastic support component is used to elastically push the ball (11) so that the ball (11) and the sealing ring (21) are in close contact; a plurality of guide grooves (22) are provided on the inner wall of the ball groove (18); when the ball (11) descends, the guide groove (22) is used to connect the upper and lower spaces of the ball (11).

6. The wafer chip lifting structure according to claim 5, characterized in that: The elastic support assembly includes a moving block (23), the moving block (23) is inserted into the interior of the bottom groove (20), the top of the moving block (23) is in sealing contact with the bottom of the vertical groove (19), a trigger rod (24) is fixed to the top of the moving block (23), the trigger rod (24) is inserted into the interior of the vertical groove (19), the top of the trigger rod (24) is in contact with the ball (11), and a pulling assembly is provided on the top surface of the moving block (23), the pulling assembly is used to pull the moving block (23) to maintain the blocking state of the moving block (23) to the vertical groove (19).

7. The wafer chip lifting structure according to claim 6, characterized in that: The pulling assembly includes an insertion rod (25), the insertion rod (25) is fixed on the top of the trigger rod (24), a slot (26) is provided on the inner wall of the contact block (9), the insertion rod (25) is inserted inside the slot (26), and a pulling spring (27) is fixed between the insertion rod (25) and the inner wall of the slot (26).

8. The wafer chip lifting structure according to claim 6, characterized in that: A blocking ring (28) and a guide tube (29) are sleeved and fixed on the outer side of the trigger rod (24); the guide tube (29) is arranged above the blocking ring (28); the side wall of the guide tube (29) has a tapered surface (30); and a conducting groove (31) is provided on the tapered surface (30) of the guide tube (29).

9. The wafer chip lifting structure according to claim 4, characterized in that: An elastic telescopic rod (32) is provided inside the lifting tube (2). The elastic telescopic rod (32) is arc-shaped. The elastic telescopic fixed end is fixed to the inner wall of the lifting tube (2). The movable end of the elastic telescopic rod (32) is provided on the turning path of the turning plate (14). There is a moving space between the movable end of the elastic telescopic rod (32) and the turning plate (14). An electromagnet (33) is fixed to the top of the extrusion piston (13). The U-shaped section of the ejector pin (5) is made of ferromagnetic material.

10. The wafer chip lifting structure according to claim 9, characterized in that: A friction strip (34) is provided between the two contact strips (17), the surface of the friction strip (34) is provided with a groove (35) adapted to the ball (11), a friction surface is provided in the groove (35), a sliding groove (36) is provided on the surface of the flip plate (14), the friction strip (34) is vertically slidably connected inside the sliding groove (36), a first rack (37) is fixed on the top surface of the friction strip (34), a gear (38) is provided on one side of the first rack (37), a second rack (39) is provided on one side of the gear (38), and the gear (38) is meshed with the first rack (37) and the second rack (39).

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