A lapping fixture with a flipping mechanism

Abstract

The application discloses a grinding clamp with a turnover mechanism, which comprises a U-shaped support mechanism, a lifting pin mechanism, a grinding clamp head and a rotating shaft, the U-shaped support mechanism comprises a fixed crossbeam and two side arms, the rotating shaft is fixedly connected with the fixed crossbeam, the side arms are connected to the two ends of the fixed crossbeam, the lower end of each side arm is provided with a lifting pin inner hole, a horizontal fixed pin is arranged in the lifting pin inner hole, the front wall and the rear wall of the lifting pin inner hole are provided with openings for avoiding the lifting pin mechanism, the lifting pin mechanism is fixed to the grinding clamp head, the lifting pin mechanism is provided with a long strip pin through hole, the lifting pin mechanism is hung on the fixed pin through the long strip pin through hole, and the rotation of the lifting pin mechanism is limited by the top of the opening in the rear wall of the lifting pin inner hole after the grinding clamp head rotates around the fixed pin. The application can conveniently turn over and keep the grinding clamp head, conveniently clean and maintain, and reduce damage to wafers and adsorption surfaces caused by suction of abrasives and blockage of vacuum pipelines.

Description

TECHNICAL FIELD

[0001] The present application relates to a turnover mechanism of a clamp, and belongs to the technical field of polishing equipment. BACKGROUND

[0002] In the surface treatment process of semiconductor wafers and materials, grinding treatment is needed. Grinding is a subtraction to the thickness, which removes a certain thickness of material to make the wafer and material as a whole thinner.

[0003] In the grinding process, the clamp clamps the wafer and material on the grinding machine for precision machining. While machining, the clamp needs to exert a certain pressure on the surface of the wafer or material to ensure that the wafer or material is correctly machined.

[0004] When the size of the wafer or material is 6 inches or more in diameter, a very large downward pressure needs to be applied to its surface. Taking 6-inch silicon as an example, according to 100 g / cm 2 It is calculated that about 17KG downward pressure needs to be applied during grinding, and greater pressure needs to be applied to hard materials such as SiC and GaN. Such large size and large pressure result in large size and heavy structure of the precision grinding clamp. The weight of the large clamp is generally more than 20KG. Therefore, in the semi-automatic grinding equipment, the large clamp usually needs to be lifted by a pneumatic cylinder or a motor, and cannot be manually carried.

[0005] In the current semi-automatic grinding equipment, the large clamp is mostly lifted and lowered by a pneumatic cylinder, and the clamp is not turned over during the whole grinding process. During the grinding process, the wafer can be directly adsorbed in the large clamp, or the wafer is bonded to a glass substrate with a thickness of about 1mm, and then adsorbed in the large clamp. However, during the grinding process, due to the grinding feed and water flushing operation, the grinding material or grinding waste liquid may enter the back of the wafer or the substrate, directly affecting the surface of the clamp adsorption surface, or blocking the holes of the adsorption surface. In the case that the clamp is not turned over, it is difficult to discover and check in time, and even if there is a simple subsequent adsorption surface flushing, there is a problem of incomplete or unclean flushing. These conditions can easily lead to poor TTV of the wafer surface after grinding and introduce contaminated particles, scratch the wafer and substrate, and affect the quality of the wafer. SUMMARY

[0006] In view of the defects of the prior art, the present application provides a grinding clamp with a turnover mechanism, which can realize the operation of turning over the clamp without disassembling the clamp, and solve the problems of poor TTV of the wafer and damage to the back of the wafer caused by the grinding material or waste liquid running to the back of the wafer during the grinding process.

[0007] The technical scheme of the present application is as follows: a grinding clamp with a turnover mechanism, comprising a U-shaped support mechanism, a lifting pin mechanism, a grinding clamp head and a rotating shaft, the U-shaped support mechanism comprises a fixed crossbeam and two side arms, the rotating shaft is fixedly connected with the fixed crossbeam, the side arms are connected to the two ends of the fixed crossbeam, the lower end of the side arm is provided with a lifting pin inner hole, a horizontally arranged fixed pin is arranged in the lifting pin inner hole, the front wall and the rear wall of the lifting pin inner hole are provided with openings for avoiding the lifting pin mechanism, the lifting pin mechanism is fixed to the grinding clamp head, the lifting pin mechanism is provided with a long strip pin through hole, the lifting pin mechanism is hung on the fixed pin through the long strip pin through hole, and the grinding clamp head is limited to rotate by the top of the opening of the rear wall of the lifting pin inner hole after rotating around the fixed pin.

[0008] Further, the middle part of the fixed pin is in a spindle shape, the two ends of the spindle shape are diameter increasing parts, and the top of the long strip pin through hole is provided with a tapered protrusion matched with the middle part of the spindle shape of the fixed pin.

[0009] Further, the top of the lifting pin mechanism is provided with a top pin vertically penetrating into the long strip pin through hole, and the bottom end of the top pin is the tapered protrusion.

[0010] Further, the front upper part of the lifting pin mechanism is provided with an anti-falling hook protruding from the side surface of the lifting pin mechanism, and the grinding clamp head is hooked on the rear wall of the lifting pin inner hole by the anti-falling hook after rotating around the fixed pin.

[0011] Further, the top of the opening of the front wall of the lifting pin inner hole is provided with an upward extending avoiding groove.

[0012] Further, the distance from the top of the opening of the rear wall of the lifting pin inner hole to the horizontal plane where the axis of the fixed pin is located is not greater than the distance from the front side of the lifting pin mechanism to the axis of the lifting pin mechanism.

[0013] Further, the distance from the top of the opening of the front wall of the lifting pin inner hole to the horizontal plane where the axis of the fixed pin is located is greater than the distance from the top of the opening of the rear wall of the lifting pin inner hole to the horizontal plane where the axis of the fixed pin is located.

[0014] Further, the openings of the front wall and the rear wall of the lifting pin inner hole are U-shaped openings.

[0015] Further, the rotating shaft is provided with a hollow hole, and the hollow hole is used for penetrating a vacuum pipe connected with the grinding clamp head.

[0016] Further, the two ends of the fixed pin are limited by a locking pin and the side wall of the lifting pin inner hole.

[0017] The technical scheme provided by the present application has the following advantages:

[0018] The present application sets the long bolt pin through hole, so that the rear push of the grinding clamp head can be limited by the opening on the rear wall of the lifting pin inner hole to the lifting pin mechanism, so that the grinding clamp head remains in the overturned state. The heavy grinding clamp head can be easily manually overturned, so that the operator can clean the grinding clamp head, thereby reducing the damage to the wafer and the adsorption surface caused by the suction of abrasive and the blockage of the vacuum pipeline. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a structural schematic diagram of the grinding clamp with the overturning mechanism.

[0020] Figure 2 is a front view structural schematic diagram of the U-shaped support mechanism.

[0021] Figure 3 is a rear view structural schematic diagram of the U-shaped support mechanism.

[0022] Figure 4 is a sectional view schematic diagram of the U-shaped support mechanism.

[0023] Figure 5 is a structural schematic diagram of the fixed bolt pin and the R-shaped locking pin.

[0024] Figure 6 is a structural schematic diagram of the lifting pin mechanism.

[0025] Figure 7 is a sectional view schematic diagram of the lifting pin mechanism.

[0026] Figure 8 is a structural schematic diagram of the grinding clamp with the overturning mechanism after overturning. DETAILED DESCRIPTION

[0027] The present application will be further described below in conjunction with the embodiments, which should be understood as only for illustrating the present application but not for limiting the scope of the present application. After reading the present description, those skilled in the art can make various modifications to the present description, which all fall within the scope defined by the appended claims.

[0028] Please combine Figure 1As shown, the grinding clamp with the turnover mechanism of the present embodiment comprises a U-shaped support mechanism 1, a lifting pin mechanism 2, a grinding clamp head 3 and a rotating shaft 4. The U-shaped support mechanism 1 is fixed on the bottom end of the rotating shaft 4 by screws. The rotating shaft 4 is a hollow shaft, and the rotating shaft 4 is provided with a through hollow hole. The upper part of the rotating shaft 4 is connected with a motor and an air cylinder (not shown), which can rotate under the driving of the motor, can rise and fall under the action of the air cylinder, and the top of the rotating shaft 4 is provided with a vacuum rotary joint (not shown), and a vacuum hose (not shown) is penetrated in the hollow hole 4a. The grinding clamp head 3 is provided with a vacuum pipe in the center and a vacuum connector (not shown) at the top, one end of the vacuum hose in the rotating shaft 4 is connected with the vacuum system through the rotary joint, and the other end is connected with the connector of the vacuum pipe at the top of the middle connecting column 301 of the grinding clamp head 3, so as to provide vacuum for the annular groove adsorption surface in the grinding clamp head 3. Moreover, the vacuum pipe connected with the grinding clamp head 3 is a telescopic hose (shown by line 5 in the figure), which is convenient for the grinding clamp head 3 to turn over without affecting the movement. The lifting pin mechanism 2 is fixed on the top surface of the grinding clamp head 3 and located on the left and right sides of the middle connecting column 301, and can be connected with the left and right arms of the U-shaped support mechanism 1 through fixed pins 103.

[0029] Please refer to Figures 2 to 4 As shown, the U-shaped support mechanism 1 mainly comprises a fixed cross beam 101 and two left and right arms 102. The central part of the fixed cross beam 101 is provided with a through hole 101a and a fixed screw hole 101b. The bottom of the rotating shaft 4 is inserted into the through hole 101a and fixed and connected with the fixed cross beam 101 by screws through the fixed screw hole 101b.

[0030] The left and right arms 102 can be fixed on the two ends of the fixed cross beam 101 by screws, or the left and right arms 102 and the fixed cross beam 101 can be welded together or integrally formed and processed. The bottom of the left and right arms 102 is provided with a longitudinal lifting pin inner hole 107. The front wall of the lifting pin inner hole 107 is provided with a front U-shaped opening 105, the rear wall of the lifting pin inner hole 107 is provided with a rear U-shaped opening 106, and the left and right walls of the lifting pin inner hole 107 are provided with pin holes 108. Please refer to Figure 5 As shown, the fixed pins 103 are connected on the left and right arms 102 and horizontally placed in the lifting pin inner hole 107 after penetrating through the pin holes 108, which are used for suspending and fixing the lifting pin mechanism 2, that is, suspending the grinding clamp head 3. In a preferred embodiment, since the fixed pins 103 need to be disassembled for suspending the lifting pin mechanism 2, in order to facilitate installation, the two ends of the fixed pins 103 are limited and fixed with the left and right walls of the lifting pin inner hole 107 through two R-shaped locking pins 104.

[0031] Please refer to Figure 6 and Figure 7As shown, the ejecting mechanism 2 is mainly composed of an ejecting column 201, a falling prevention hook 202 and a fixing flange 204. The ejecting column 201 is vertically arranged on the fixing flange 204, and the fixing flange 204 is fixedly connected with the left and right sides of the middle connecting column 301 of the grinding clamp head 3 through a plurality of fixing screw holes. The ejecting column 201 is provided with a longitudinal long bolt pin through hole 203, and the through direction of the long bolt pin through hole 203 is the left-right direction. The long bolt pin through hole 203 enables the ejecting mechanism 2 to move in the longitudinal direction of the ejecting column 201, that is, the length direction of the long bolt pin through hole 203 after being hung on the fixed pin bolt 103. The falling prevention hook 202 is arranged on the front side upper part of the ejecting column 201 and protrudes from the side surface of the ejecting column 201. Correspondingly, the top of the front U-shaped opening 105 is also provided with an upward extending avoiding groove 105a to avoid the falling prevention hook 202 when the ejecting column 201 moves up and down.

[0032] In a preferred embodiment, the middle part 103a of the fixed pin bolt 103 is spindle-shaped, and a tapered protrusion matching the spindle shape is arranged on the top wall of the long bolt pin through hole 203. When the ejecting mechanism 2 is hung on the fixed pin bolt 103, the tapered protrusion is limited by the diameter increasing parts 103b at both ends of the spindle shape, which limits the axial movement of the ejecting mechanism 2 on the fixed pin bolt 103. In this embodiment, a vertical top pin 205 is screwed into the top of the ejecting column 201, and the bottom end of the top pin 205 extends into the long bolt pin through hole 203 to form the aforementioned tapered protrusion.

[0033] After the overall connection, when the rotating shaft 4 is lifted and lowered under the action of the air cylinder, the U-shaped support mechanism 1 and the grinding clamp head 3 will also be lifted and lowered; when the rotating shaft 4 is rotated under the action of the motor, the U-shaped support mechanism 1 and the grinding clamp head 3 will also be rotated.

[0034] The specific use and overturning method is as follows:

[0035] First step: clamp installation

[0036] The U-shaped support mechanism 1 is lowered to the designated position by controlling the cylinder, and the fixing pins 103 in the left and right bolt holes 108 of the side arm 102 are pulled out. The grinding jig head 3 is placed on the grinding disc, and then the grinding disc is rotated to bring the grinding jig head 3 closer to the U-shaped support mechanism 1. The grinding jig head 3 is moved so that its lifting pin mechanism 2 is aligned with the side arm 102 of the U-shaped support mechanism 1. Then, the grinding jig head 3 is pushed into the lifting pin inner hole 107 through the front U-shaped opening 105, so that the lifting pin mechanism 2 is in the lifting pin inner hole 107. The height and angle of the U-shaped support mechanism 1 are adjusted appropriately so that its fixing pins 103 can pass through the elongated bolt through hole 203 of the lifting pin mechanism 2 and the bolt hole 108 on the side arm 102. Then, the fixing pins 103 are locked with R-type locking pins 104. After ensuring that the left and right fixing pins 103 are inserted and locked, the cylinder can be controlled to raise the U-shaped support mechanism 1, and the grinding jig head 3 is raised together. At this time, the grinding jig head 3 is lifted a certain height from the disc surface, and the lifting pin mechanism 2 lifts the entire grinding jig head 3 and suspends it on the fixed pin 103. The grinding jig head 3 can swing freely back and forth around the axis of the fixed pin 103.

[0037] The second step is to manually flip the item upwards, which involves four steps: flip, lift, push, and place.

[0038] In a preferred embodiment, the distance from the top of the rear U-shaped opening 106 of the lifting pin inner hole 107 to the horizontal plane where the axis of the fixing pin 103 lies is not greater than the distance from the front side of the lifting pin post 201 to the axis of the lifting pin post 201. The distance from the top of the front U-shaped opening 105 of the lifting pin inner hole 107 to the horizontal plane where the axis of the fixing pin 103 lies is greater than the distance from the top of the rear U-shaped opening 106 of the lifting pin inner hole 107 to the horizontal plane where the axis of the fixing pin 103 lies, that is, the length of the front U-shaped opening 105 is greater than the rear U-shaped opening 106, so that the rotating grinding jig head 3 can be in a nearly horizontal state. Please refer to... Figure 8 As shown, when the grinding jig head 3 is in the raised state, it is freely suspended from the fixed pin 103 by the lifting pin mechanism 2. Hold the left and right edges of the grinding jig head 3 with both hands, and rotate / flip it around the axis of the fixed pin 103. When the grinding jig head 3 flips to a horizontal position, hold it firmly and slightly raise it so that the anti-fall hook 202 is below the top of the groove of the rear U-shaped opening 106. At this time, the lifting pin 201 can pass through the rear U-shaped opening 106. Then push the grinding jig head 3 backward until it cannot be pushed any further, so that the top of the lifting pin 201 passes through the rear U-shaped opening 106 and exposes the anti-fall hook 202, placing it outside the inner hole 107 of the lifting pin. Next, continue to hold the left and right sides of the grinding jig head 3 with both hands and gently lower it. When the lifting pin 201 contacts the top of the rear U-shaped opening 106, the grinding jig head 3 is supported, and the flipping is complete.

[0039] In a preferred embodiment, the horizontal distance from the top of the groove of the rear U-shaped opening 106 to the axis of the fixing pin 103 is the same as the distance from the axis of the fixing pin 103 to the front surface of the lifting pin 201. Thus, the annular adsorption surface of the grinding jig head 3 after being flipped over can be approximately vertical, allowing for operations such as cleaning / inspection / sample adsorption. The aforementioned anti-fall hook 202 can hook onto the wall of the inner hole 107 of the lifting pin, preventing the grinding jig head 3 from accidentally sliding forward after being flipped over and escaping the restraint of the rear U-shaped opening 106, thus preventing accidents.

[0040] The third step is to unflip the object, which involves three steps: lifting, pulling, and releasing. This restores the object from its flipped state to its suspended state.

[0041] Hold the left and right edges of the grinding jig head 3 with both hands, slightly raise the grinding jig head 3, and then pull the grinding jig head 3 forward so that the lifting pin 201 passes back into the U-shaped opening 106 and the anti-fall hook 202 returns to the inner hole 107 of the lifting pin. Then gently lower the grinding jig head 3. At this time, the grinding jig head 3 can return to the state of freely hanging on the fixing pin 103, as... Figure 1 As shown.

[0042] Experimental verification shows that the grinding fixture with a flipping mechanism of the present invention is time-saving, labor-saving, simple and convenient to operate, and can effectively reduce the workload of operators; it can solve the problems of wafer TTV deterioration and wafer back scratch damage caused by grinding material or waste liquid running to the back of the wafer during the grinding process; it also reduces the scrap rate and increases the wafer yield, while effectively reducing the maintenance time of vacuum pipeline and grinding fixture head.

Claims

1. A grinding fixture with a flipping mechanism, characterized in that, The device includes a U-shaped support mechanism, a lifting pin mechanism, a grinding fixture head, and a rotating shaft. The U-shaped support mechanism includes a fixed crossbeam and two side arms. The rotating shaft is fixedly connected to the fixed crossbeam. The side arms are connected to both ends of the fixed crossbeam. The lower end of each side arm has a lifting pin inner hole. A horizontally placed fixing pin is provided in the lifting pin inner hole. The front and rear walls of the lifting pin inner hole have openings to avoid the lifting pin mechanism. The lifting pin mechanism is fixed to the grinding fixture head. The lifting pin mechanism has an elongated pin through hole. The lifting pin mechanism is suspended from the fixing pin through the elongated pin through hole. After the grinding fixture head rotates around the fixing pin, the rotation of the lifting pin mechanism is restricted by the top of the opening on the rear wall of the lifting pin inner hole.

2. The grinding fixture with a flipping mechanism according to claim 1, characterized in that, The middle part of the fixing pin is spindle-shaped, and the two ends of the spindle shape are diameter-increased portions. The top of the elongated pin through hole is provided with a conical protrusion that matches the middle part of the spindle shape of the fixing pin.

3. The grinding fixture with a flipping mechanism according to claim 2, characterized in that, The top of the lifting mechanism is provided with a top pin that is vertically inserted into the long strip bolt hole, and the bottom end of the top pin is the conical protrusion.

4. The grinding fixture with a flipping mechanism according to claim 1, characterized in that, The upper front part of the lifting pin mechanism is provided with a fall-prevention hook protruding from the side surface of the lifting pin mechanism. After the grinding jig head rotates around the fixed pin, it is hooked by the fall-prevention hook onto the rear wall of the inner hole of the lifting pin.

5. The grinding fixture with a flipping mechanism according to claim 4, characterized in that, The top of the opening in the front wall of the inner hole of the lifting pin is provided with an upwardly extending clearance groove.

6. The grinding fixture with a flipping mechanism according to claim 1, characterized in that, The distance from the top of the opening on the rear wall of the lifting pin's inner hole to the horizontal plane where the axis of the fixing pin is located is not greater than the distance from the front side of the lifting pin mechanism to the axis of the lifting pin mechanism.

7. The grinding fixture with a flipping mechanism according to claim 6, characterized in that, The distance from the top of the opening on the front wall of the inner hole of the lifting pin to the horizontal plane where the axis of the fixing pin is located is greater than the distance from the top of the opening on the rear wall of the inner hole of the lifting pin to the horizontal plane where the axis of the fixing pin is located.

8. The grinding fixture with a flipping mechanism according to claim 1, characterized in that, The openings on the front and rear walls of the inner hole of the lifting pin are U-shaped.

9. The grinding fixture with a flipping mechanism according to claim 1, characterized in that, The rotating shaft has a hollow hole, which is used to pass through the vacuum tube connected to the grinding fixture head.

10. The grinding fixture with a flipping mechanism according to claim 1, characterized in that, The two ends of the fixing pin are limited by locking pins to the side wall of the inner hole of the lifting pin.

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