A pressing head and a wafer polishing device having the pressing head

Abstract

The present application provides a pressure head for providing downward pressure on a wafer, pressing the wafer against the upper surface of a working disk for polishing. In the field of semiconductor equipment processing technology, the pressure head comprises a driving part, a main shaft, a connecting part and a pressure plate connected in sequence; the driving part is used to drive the main shaft to perform lifting and lowering movements, thereby driving the connecting part and the pressure plate to perform lifting and lowering movements; the connecting part is connected between the main shaft and the pressure plate, and the connecting part has a connection state in which the pressure plate is connected to the main shaft by the gravity of the pressure plate before the pressure plate abuts against the wafer, and a disengagement state in which the pressure plate is disengaged from the main shaft due to the upward supporting force provided by the working disk when the pressure plate descends with the main shaft to abut against the wafer; in the connection state, the pressure plate performs lifting and lowering movements together with the main shaft, and in the disengagement state, the pressure plate does not perform lifting and lowering movements with the main shaft.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor equipment processing, and in particular to a pressing head and a wafer polishing device having the pressing head. Background Art

[0002] In the chip manufacturing process, the smoothness of each wafer is crucial. A smooth wafer surface is the key to flattening in the process. Especially in each photolithography process, the extreme flatness of the wafer surface is particularly important. In order to meet the demand, the wafer will undergo multiple polishing in the process to reduce its roughness and ups and downs and remove excess surface substances.

[0003] When polishing a wafer, it is necessary to press the wafer onto the working plate through a pressure plate, and the working plate polishes the surface of the wafer. In the existing technology, the pressure plate often provides downward pressure through a cylinder or a motor, but the downward pressure provided by this method often has the problem of unstable downward pressure and difficult to accurately control. When the pressure plate contacts the wafer and pressurizes it, due to inaccurate control of the downward pressure, the downward pressure may be too much, which may affect the polishing accuracy of the wafer, or even damage the wafer. Summary of the invention

[0004] The purpose of the present application is to provide a pressure head and a wafer polishing device having the pressure head, aiming to solve the defect in the related art that the downward pressure is unstable and thus excessive pressure is applied, resulting in damage to the wafer.

[0005] Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.

[0006] According to a first aspect of the present application, there is provided a pressing head for providing downward pressure on a wafer, pressing the wafer against the upper surface of a working plate for polishing, the pressing head comprising a driving part, a spindle, a connecting part and a pressing plate connected in sequence;

[0007] The driving part is used to drive the main shaft to perform lifting movement, thereby driving the connecting part and the pressure plate to perform lifting movement;

[0008] The connecting portion is connected between the main shaft and the pressure plate, and the connecting portion has: a connected state in which the pressure plate is connected to the main shaft by the gravity of the pressure plate before the pressure plate abuts against the wafer, and a disengaged state in which the pressure plate is disengaged from the main shaft due to the upward supporting force provided by the working plate when the pressure plate is lowered along with the main shaft to abut against the wafer; in the connected state, the pressure plate performs a lifting and lowering movement together with the main shaft, and in the disengaged state, the pressure plate does not perform a lifting and lowering movement together with the main shaft.

[0009] In an exemplary embodiment of the present application, the connecting part includes a connecting rod and a buffer assembly, the connecting rod is fixedly connected to the pressure plate, the main shaft is connected to the connecting rod through the buffer assembly, and the buffer assembly is configured to gradually disengage the pressure plate from the main shaft when the connecting part switches from the connected state to the disengaged state, and when the pressure plate and the main shaft are in the disengaged state, the main shaft does not rotate with the pressure plate.

[0010] In an exemplary embodiment of the present application, the buffer assembly includes a first buffer and a second buffer that are relatively arranged, the first buffer is fixedly connected to the main shaft, the second buffer is fixedly connected to the connecting rod, and the opposite side of the first buffer and the second buffer constitutes a wedge structure for preventing the pressure plate from falling.

[0011] In an exemplary embodiment of the present application, the connecting portion also includes a connecting cover, which is fixedly connected to the bottom of the main shaft, and the bottom of the connecting cover passes through the interior of the connecting cover. The first buffer member is fixedly connected to the inner wall of the connecting cover, and the second buffer member is fixedly connected to the outer wall of the top of the connecting rod. The top of the connecting rod extends from the bottom of the connecting cover into the connecting cover, and the opposite sides of the first buffer member and the second buffer member are both inclined surfaces that are gradually inclined inward from top to bottom.

[0012] In an exemplary embodiment of the present application, the connecting part also includes a connecting cover, which is fixedly connected to the top of the connecting rod, and the top of the connecting cover passes through the interior of the connecting rod. The first buffer member is fixedly connected to the outer wall of the bottom of the main shaft, and the second buffer member is fixedly connected to the inner wall of the connecting cover. The bottom of the main shaft extends from the top of the connecting cover into the connecting cover, and the opposite sides of the first buffer member and the second buffer member are both inclined surfaces that are gradually inclined outward in a top-down direction.

[0013] In an exemplary embodiment of the present application, a counterweight is further included for increasing the downward pressure of the pressure plate. The counterweight is arranged above the pressure plate, and the counterweight is arranged to be adjustable in its weight.

[0014] In an exemplary embodiment of the present application, the counterweight member is configured as a plurality of counterweight plates, each of which is configured as a semicircular ring, and a plurality of the counterweight plates are stacked above the pressure head to form a multi-layer counterweight structure, and the counterweight plates in each layer of the counterweight structure are configured as two, and the two counterweight plates are arranged opposite to each other.

[0015] In an exemplary embodiment of the present application, the pressure head further includes a fixed anti-falling component, the anti-falling component includes a key pin, and the outer wall of the main shaft is provided with a socket adapted to be plugged into the key pin.

[0016] In an exemplary embodiment of the present application, the pressure head also includes a fixed anti-fall component, the anti-fall component includes a key pin, the outer wall of the main shaft is provided with a socket adapted to be plugged into the key pin, and the key pin can move horizontally in a direction toward the socket, but is restricted in the vertical direction.

[0017] In an exemplary embodiment of the present application, a main rod is penetrated inside the main shaft, and the main rod can be slidably connected with the main shaft along the length direction of the main shaft. A first air duct is formed inside the main rod along its own length direction, and the first air duct runs through both ends of the main rod. A second air duct is formed in the connecting rod, and the second air duct runs through the top of the connecting rod and is connected to the first air duct. An inflation device is connected to the top of the main rod, and the inflation device is communicated with the interior of the first air duct.

[0018] In an exemplary embodiment of the present application, a connecting frame for connecting and fixing the output end of the driving unit and the main shaft is provided between the output end of the driving unit and the main shaft, and the connecting frame includes:

[0019] A connecting plate, located below the driving unit, and an output end of the driving unit is fixedly connected to the connecting plate;

[0020] A movable plate, located below the connecting plate, and the main shaft is fixedly connected to the movable plate;

[0021] The support rod is fixedly connected between the connecting plate and the movable plate.

[0022] In an exemplary embodiment of the present application, the pressure head further comprises a main frame for mounting various components, and the main frame comprises:

[0023] A top plate is arranged above the connecting plate, and the body of the driving unit is fixedly mounted on the top plate;

[0024] A bottom plate, disposed between the movable plate and the connecting cover, wherein the main shaft penetrates through the bottom plate and is slidably connected to the bottom plate;

[0025] A guide post is fixedly connected between the top plate and the bottom plate, and the guide post passes through the movable plate and is slidably connected with the movable plate along its own length direction.

[0026] In an exemplary embodiment of the present application, a mounting plate is provided between the connecting plate and the inflatable device, the inflatable device is fixedly connected to the mounting plate, the mounting plate is provided with a guide hole, and the support rod passes through the guide hole and is slidably connected to the mounting plate.

[0027] According to a second aspect of the present application, a wafer polishing device is provided, characterized in that it comprises a pressing head as described in any one of the above items.

[0028] In an exemplary embodiment of the present application, it further includes:

[0029] A working plate, used for grinding the surface of the wafer, the pressing head is located above the working plate, and the pressing head is used for pressing the wafer onto the working plate;

[0030] A driving device is used to drive the working disk to rotate.

[0031] The exemplary embodiments of the present application may have some or all of the following beneficial effects:

[0032] In a pressure head provided in the example implementation of the present application, the driving unit drives the spindle, the connecting part and the pressure plate to move downward together. When the pressure plate presses the wafer on the working plate, the driving unit continues to provide the power for downward movement, which will cause the spindle and the pressure plate to form a disengaged state. At this time, the driving unit can only drive the spindle to continue to move downward, and cannot apply pressure to the connecting part and the pressure plate; therefore, during grinding, the wafer can be pressed only by the weight of the pressure plate itself; after grinding is completed, the driving unit drives the spindle to move upward, and the spindle and the pressure plate resume the connection state, so that the driving unit can drive the pressure plate to move together. Through the above structure, when the pressure plate presses the wafer on the working plate, it only plays a pressing role by its own weight, and the driving unit cannot apply downward pressure, so that the downward pressure of the pressure plate on the wafer reaches a stable state and is not easy to be applied too much, thereby having a good protective effect on the wafer.

[0033] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 A schematic diagram of the structure of a pressure head in an embodiment of the present application is shown;

[0036] Figure 2 A cross-sectional view of a pressure head in an embodiment of the present application is shown;

[0037] Figure 3 Shows Figure 2 Enlarged view of part A.

[0038] Description of reference numerals:

[0039] 1. Driving unit; 2. Main shaft; 21. Socket; 22. Main rod; 221. First air channel; 3. Connecting unit; 31. Connecting rod; 311. Second air channel; 32. Buffer assembly; 321. First buffer; 322. Second buffer; 33. Connecting cover; 4. Pressure plate; 5. Counterweight; 6. Anti-fall assembly; 61. Key pin; 62. Power unit; 7. Inflating device; 8. Connecting frame; 81. Connecting plate; 82. Moving plate; 83. Support rod; 9. Main frame; 91. Top plate; 92. Bottom plate; 93. Guide column; 10. Mounting plate; 101. Guide hole. DETAILED DESCRIPTION Example 1

[0040] Reference Figure 1 and Figure 2 As shown, in an embodiment of the present application, a pressing head is provided, which is used to provide downward pressure on a wafer, and press the wafer on the upper surface of a working plate for grinding. The pressing head includes a driving part 1, a spindle 2, a connecting part 3 and a pressing plate 4 which are connected in sequence;

[0041] The driving part 1 is used to drive the main shaft 2 to perform lifting motion, thereby driving the connecting part 3 and the pressure plate 4 to perform lifting motion;

[0042] The connecting portion 3 is connected between the main shaft 2 and the pressure plate 4, and the connecting portion 3 has a connection state in which the pressure plate 4 is connected to the main shaft 2 by the gravity of the pressure plate 4 before the pressure plate 4 abuts against the wafer, and a disengagement state in which the pressure plate 4 is disengaged from the main shaft 2 due to the upward supporting force provided by the working plate when the pressure plate 4 is lowered along with the main shaft 2 to abut against the wafer; in the connection state, the pressure plate 4 performs a lifting and lowering movement together with the main shaft 2; in the disengagement state, the pressure plate 4 does not perform a lifting and lowering movement along with the main shaft 2.

[0043] In the embodiment of the present application, the driving unit 1 guides the pressure plate 4 to slowly descend until the pressure plate 4 is in close contact with the wafer, and then the pressure plate 4 is separated from the spindle 2 to ensure that the wafer surface only bears the deadweight of the pressure plate 4. Specifically, when the wafer needs to be polished, the driving device first drives the spindle 2 to move downward. When the pressure plate 4 has not yet contacted the wafer surface, the connecting portion 3 maintains the connection state between the pressure plate 4 and the spindle 2, so that the spindle 2 and the pressure plate 4 are synchronously descended until the pressure plate 4 contacts the wafer; after contact, the connecting portion 3 causes the pressure plate 4 to separate from the spindle 2. At this time, even if the driving device continues to drive the spindle 2 to descend, no additional downward pressure will be applied to the pressure plate 4. Therefore, during the polishing process, the wafer only bears the deadweight of the pressure plate 4, and there is no additional force. Therefore, by adopting the pressure head in the embodiment of the present application, it is only necessary to pre-set the deadweight of the pressure plate 4 as the pressure required for polishing. This structure ensures that the downward pressure of the wafer during polishing has good stability. Compared with the traditional technology, the pressure plate 4 provides additional downward pressure through the cylinder or motor, resulting in the pressure on the wafer not only including the weight of the pressure plate 4, but also the downward pressure provided by the cylinder or motor, making the pressure on the wafer unstable and difficult to control. In comparison, the present application significantly improves the stability of the pressure on the wafer by optimizing the connection mechanism between the pressure plate 4 and the spindle 2, which not only improves the polishing quality of the wafer, but also effectively avoids the risk of damage to the wafer during processing.

[0044] Reference Figure 2 and Figure 3 As shown, further, the connection part 3 includes a connection rod 31 and a buffer assembly 32, the connection rod 31 is arranged along the vertical direction, and the bottom of the connection rod 31 is fixedly connected to the center of the upper surface of the pressure plate 4. The buffer assembly 32 plays a role when the connection part 3 is converted from the connected state to the disengaged state, ensuring the gradual separation of the pressure plate 4 and the spindle 2, that is, the pressure plate 4 is gradually separated from the spindle 2 after abutting the working plate. The advantage of this effect is that the pressure on the wafer can rise smoothly to the deadweight of the pressure plate 4, and then remain stable, rather than suddenly reaching the deadweight of the pressure plate 4. This avoids the wafer from being damaged due to an instantaneous surge in pressure, and provides effective protection for the wafer by gradually applying pressure, ensuring the safety of the processing process and the integrity of the wafer.

[0045] In the embodiment of the present application, when the pressure plate 4 is in a separated state from the spindle 2, the spindle 2 will not rotate with the pressure plate 4. Specifically, when the spindle 2 is separated from the pressure plate 4, the connecting portion 3 ensures that the two are connected in a rotationally free manner. During the wafer polishing process, the working disc drives the wafer to rotate, and the pressure plate 4 rotates synchronously therewith, thereby maintaining the relative static state between the wafer and the pressure plate 4, avoiding friction between the two, and polishing the wafer only by the working disc, further improving the polishing quality of the wafer. In addition, since the pressure plate 4 and the spindle 2 can be separated, the pressure plate 4 can rotate freely with the wafer, and there is no need to additionally configure the rotation drive device of the pressure plate 4. In the prior art, since the pressure plate 4 and the spindle 2 cannot be separated, in order to keep the pressure plate 4 and the wafer relatively static, a rotation drive device must be added to the spindle 2 to drive the pressure plate 4 and the wafer to rotate synchronously. Therefore, the present application effectively reduces the manufacturing cost of the equipment and improves the economy and practicality of the equipment by optimizing the connection mechanism between the pressure plate 4 and the spindle 2.

[0046] In the embodiment of the present application, the buffer assembly 32 is composed of a first buffer 321 and a second buffer 322, which are arranged opposite to each other, wherein the first buffer 321 is fixedly connected to the main shaft 2, and the second buffer 322 is fixedly connected to the connecting rod 31. The opposite surfaces of the first buffer 321 and the second buffer 322 abut against each other, and together form a wedge-shaped structure, which is used to prevent the pressure plate 4 from falling freely. Specifically, when the main shaft 2 drives the pressure plate 4 to rise or fall, the second buffer 322 is in close contact with the first buffer 321 due to the deadweight of the pressure plate 4, and the two are relatively fixed by friction. When the pressure plate 4 contacts the surface of the wafer, the pressure on the wafer is zero. At this time, the driving device continues to drive the main shaft 2 to move downward, and the pressure on the surface of the wafer gradually increases until the first buffer 321 and the second buffer 322 overcome the friction between each other and enter a separated state. At this time, the pressure on the surface of the wafer is completely equivalent to the deadweight of the pressure plate 4, ensuring the pressure stability and wafer processing quality during the grinding process.

[0047] In the embodiment of the present application, the connecting portion 3 further includes a connecting cover 33 , the interior of which is configured as a hollow cavity for assembling the first buffer component 321 or the second buffer component 322 , thereby providing a stable installation environment for the buffer component 32 .

[0048] In a specific implementation of the embodiment of the present application, the connection cover 33 is fixedly connected to the bottom of the main shaft 2. At this time, the connection cover 33 forms a through structure from the bottom to the inside, and the top of the connecting rod 31 penetrates into the internal space of the connection cover 33 from the bottom. The first buffer 321 is circumferentially fixed to the inner wall of the connection cover 33, and the second buffer 322 is circumferentially fixed to the outer wall of the connecting rod 31. In this structural layout, in order to effectively prevent the risk of the pressure plate 4 falling, the wedge structure formed by the opposite surfaces of the first buffer 321 and the second buffer 322 needs to be gradually tilted inward from the top to the bottom, ensuring the stability and safety of the pressure plate 4 during operation.

[0049] Another variant implementation in the embodiment of the present application is that the connection cover 33 is fixedly connected to the top of the connection rod 31. At this time, the connection cover 33 forms a through structure from the top to the inside, and the bottom end of the main shaft 2 penetrates into the internal space of the connection cover 33 from the top. The first buffer 321 is circumferentially fixed to the outer wall of the main shaft 2, and the second buffer 322 is circumferentially fixed to the inner wall of the connection cover 33. In this structural layout, in order to effectively prevent the risk of the pressure plate 4 falling, the wedge structure formed by the opposite surfaces of the first buffer 321 and the second buffer 322 needs to be gradually tilted outward from the top to the bottom, ensuring the stability and safety of the pressure plate 4 during operation.

[0050] Through the wedge structure described above, not only the connection between the main shaft 2 and the pressure plate 4 is achieved, ensuring that the pressure plate 4 will not fall accidentally under any operating conditions; at the same time, when the pressure plate 4 is suspended above the wafer, the first buffer member 321 and the second buffer member 322 can achieve close contact through friction, so as to achieve the purpose of gradually and smoothly increasing the pressure on the wafer after the pressure plate 4 abuts against the working plate.

[0051] Reference Figure 1 and Figure 2 As shown, in the embodiment of the present application, considering that there are differences in the pressures required to be applied when processing wafers of different specifications, in order to realize the adjustable downward pressure applied by the pressure plate 4 to the wafer, an adjustable counterweight is arranged above the pressure plate 4. The adjustment method of the counterweight is not specifically limited. One feasible implementation method is to provide a liquid storage tank above the pressure plate 4, and to achieve counterweight by injecting liquid into the liquid storage tank. By controlling the content of the liquid in the liquid storage tank, the counterweight of the pressure plate 4 can be effectively adjusted, and then the pressure applied to the wafer can be adjusted to ensure the adaptability and flexibility of the wafer processing process.

[0052] Further, in order to improve the stability of the pressure on the wafer after counterweighting, it is preferred to use a counterweight of solid structure. Compared with a liquid counterweight, the solid structure is more stable in shape during wafer processing, and there will be no fluctuation during the rotation of the pressure plate 4, thereby providing a more constant downward pressure for the pressure plate 4. In the embodiment of the present application, the counterweight is composed of a plurality of counterweight plates 5. Specifically, the cross section of the counterweight plate 5 is designed to be a semicircular ring, and a plurality of counterweight plates 5 are stacked on the pressure plate 4 to form a multi-layer counterweight structure. Each layer of the counterweight structure includes two counterweight plates 5 arranged opposite to each other, and the through hole formed in the middle of the two semicircular ring counterweight plates 5 matches the connecting rod 31, and the connecting rod 31 passes through the through hole and contacts the inner wall of the counterweight plate 5. By increasing or decreasing the number of counterweight plates 5, the counterweight of the pressure plate 4 can be adjusted, and then the downward pressure applied to the wafer can be adjusted. In order to enhance the stability between the pressure plate 4 and the counterweight structure, a reinforcement structure can be added between the two to ensure that there is no relative sliding between the pressure plate 4 and the counterweight structure when the pressure plate 4 rotates. The specific form of the reinforcement structure is not specifically limited. One possible implementation is to fix a reinforcement rod in the vertical direction on the top of the pressure plate 4, and a reinforcement hole matching the reinforcement rod is opened on the counterweight plate 5. When the counterweight plate 5 is placed, the reinforcement rod passes through the reinforcement hole to achieve a stable connection between the pressure plate 4 and the counterweight structure.

[0053] In an embodiment of the present application, the pressure head also includes an anti-falling component 6 for preventing the spindle 2 from accidentally falling. The anti-falling component 6 includes a key pin 61, which can only move in the horizontal direction and is restricted in the vertical direction. The side wall of the spindle 2 is provided with a socket 21, and the key pin 61 can be inserted into the socket 21. Once the key pin 61 is inserted into the socket 21 in the horizontal direction, the spindle 2 is locked and cannot fall, effectively avoiding the risk of damage to the wafer due to the accidental fall of the spindle 2. When the movement of the pressure plate 4 needs to be adjusted during processing, the key pin 61 only needs to be pulled out horizontally from the socket 21 to unlock the lock, realize the lifting and lowering movement of the pressure plate 4, and ensure the flexibility and safety of the equipment operation.

[0054] Furthermore, in order to facilitate the movement of the key pin 61, the anti-fall component 6 also includes a power device 62 for driving the key pin 61 to move horizontally. The power device 62 can be set as a linear motor or a cylinder. Of course, the above is only an exemplary description of the specific structure of the power device 62. There is no limitation on the specific structure of the power device 62. As long as it can drive the key pin 61 to move horizontally, it is acceptable.

[0055] In the embodiment of the present application, a main rod 22 is provided inside the main shaft 2, and the main shaft 2 can slide along the length direction of the main rod 22. A first air channel 221 is formed inside the main shaft 2 along its own length direction, and the first air channel 221 runs from the top of the main shaft 2 to the bottom of the main shaft 2. A second air channel 311 is formed along its own length direction on the connecting rod 31, and the second air channel 311 runs through the top of the connecting rod 31 and is connected to the bottom of the first air channel 221. An inflator 7 is installed on the top of the first air channel 221. When the pressure plate 4 is placed on the surface of the wafer, the counterweight surrounds the connecting rod 31 to provide downward pressure for the pressure plate 4, in order to ensure that the pressure distribution above the pressure plate 4 is more uniform, the inflator 7 inflates the first air channel 221, and the gas then enters the second air channel 311. The amount of inflation is adjusted until the air pressure generated in the second air channel 311 is equal to the pressure of the counterweight on the pressure plate 4, thereby ensuring that the wafer is subjected to the same pressure at each position, thereby further improving the polishing quality and processing accuracy of the wafer.

[0056] In the embodiment of the present application, the pressure head further includes a connecting frame 8, which is used to connect the driving part 1 and the main shaft 2, so that the driving part 1 can drive the main shaft 2 to move up and down.

[0057] Specifically, the connecting frame 8 includes:

[0058] A connecting plate 81 is located below the driving unit 1, and an output end of the driving unit 1 is fixedly connected to the connecting plate 81;

[0059] The movable plate 82 is located below the connecting plate 81, and the main shaft 2 is fixedly connected to the movable plate 82;

[0060] The support rod 83 is fixedly connected between the connecting plate 81 and the moving plate 82 .

[0061] In the embodiment of the present application, the driving part 1 is set as a driving cylinder, the end of its piston rod is fixedly connected to the center of the connecting plate 81, and the support rod 83 is set as four, and the four support rods 83 are respectively fixed at the four corners of the connecting plate 81 and the movable plate 82, forming a stable support structure, which enhances the rigidity and balance of the overall structure. The main shaft 2 passes through the movable plate 82 and is fixedly connected to the movable plate 82. The specific fixing method is that a mounting groove of an annular structure is provided on the circumferential outer wall of the main shaft 2, and a fixed plate is provided on the outer wall of the main shaft 2. The fixed plate is clamped in the mounting groove and connected and fixed to the movable plate 82 by bolts. Through the above structure, the connection and fixation between the driving part 1 and the main shaft 2 are realized, so that the driving part 1 can drive the movement of the main shaft 2 in the vertical direction. It can be understood that the above content is only an exemplary description, and the connection structure between the driving part 1, the connecting plate 81, the movable plate 82, the support rod 83 and the components is not limited to this.

[0062] In the embodiment of the present application, the pressure head further includes a main frame 9, which is used to fix the various components in a dark rotation manner, thereby providing good stability for the various components.

[0063] Specifically, the main frame 9 includes:

[0064] A top plate 91 is disposed above the connecting plate 81, and the body of the driving unit 1 is fixedly mounted on the top plate 91;

[0065] A bottom plate 92 is disposed between the moving plate 82 and the connecting cover 33, and the main shaft 2 passes through the bottom plate 92 and is slidably connected to the bottom plate 92;

[0066] The guide post 93 is fixedly connected between the top plate 91 and the bottom plate 92 . The guide post 93 passes through the movable plate 82 and is slidably connected to the movable plate 82 along its length direction.

[0067] In the embodiment of the present application, the cylinder body of the driving cylinder is placed above the top plate 91 and is fixedly connected to the top plate 91 by bolts, thereby ensuring the stability of the driving cylinder and providing a solid support foundation for the driving unit 1, thereby ensuring the stability and reliability of the driving unit 1 during operation. The piston rod of the driving cylinder passes through the top plate 91 and extends to the bottom of the top plate 91, thereby achieving effective transmission of power. Four guide posts 93 are provided, and the four guide posts 93 are respectively fixedly connected to the four corners of the top plate 91 and the bottom plate 92 to form a stable support frame, thereby enhancing the rigidity and balance of the overall structure. The four corners of the movable plate 82 are provided with perforations, and the movable plate 82 is fixedly connected with a shaft sleeve inside the perforations, and the guide posts 93 pass through the shaft sleeves, thereby ensuring the stability of the guide posts 93 and the precise guidance of the movable plate 82. By fixing the guide post 93 between the top plate 91 and the bottom plate 92, the stability of the guide post 93 is enhanced, so that the guide post 93 provides a guiding function for the moving plate 82, ensuring the stability and reliability of the moving plate 82 when sliding along the length direction of the guide post 93, thereby maintaining good stability during the movement. It can be understood that the above content is only an exemplary description, and the top plate 91, the bottom plate 92, the connecting post and the connection structure between the components are not limited thereto.

[0068] In the embodiment of the present application, the pressure head also includes a mounting plate 10, which is located between the inflation device 7 and the top plate 91. The inflation device 7 is fixedly connected to the mounting plate 10. The mounting plate 10 is provided with four guide holes 101. Four support rods 83 pass through the four guide holes 101 respectively. The support rods 83 are vertically slidably connected to the mounting plate 10 in the guide holes 101.

[0069] When the pressure plate 4 is in close contact with the upper surface of the working plate, the driving device continues to drive the main shaft 2 to move downward, providing continuous downward power, prompting the main shaft 2 to move further downward. Until the first buffer 321 is separated from the second buffer 322, relative sliding occurs between the main shaft 2 and the main rod 22, and the main shaft 2 continues to move downward, while the main rod 22 remains stationary. This means that the connecting plate 81, the support rod 83 and the movable plate 82 will continue to move downward, while the mounting plate 10 stops moving downward, and the mounting plate 10 and the support rod 83 slide relative to each other in the vertical direction. The smooth sliding of the support rod 83 in the guide hole 101 ensures the stability and reliability of the entire movement process, providing precise positioning and support for subsequent processing. Example 2

[0070] A wafer polishing device is disclosed in an embodiment of the present application, including a pressing head in Example 1.

[0071] In an embodiment of the present application, the wafer polishing device also includes a working disk and a driving device.

[0072] Specifically, there is one working disk, a driving device is arranged at the center of the working disk, and the working disk is driven to rotate by the driving disk. The number of pressure heads is set to be multiple, and the multiple pressure heads are arranged in a uniformly spaced manner around the top of the working disk, and the distance between each pressure head and the rotation axis of the working disk is equal. There is no special restriction on the specific number of pressure plates 4 in the embodiment of the present application. Through the above structure, when the driving device drives the working disk to rotate, each pressure head presses a wafer, so that the wafer polishing device can polish multiple wafers at the same time, which improves the processing efficiency of the wafer. Of course, it is also possible to have only one pressure head on the working disk.

[0073] Those skilled in the art will easily think of other embodiments of the present application after considering the specification and practicing the embodiments of the present application. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that the present application does not apply for. The specification and embodiments are only regarded as exemplary, and the true scope and spirit of the present application are pointed out by the appended claims.

Claims

1. A pressing head, used to provide downward pressure on a wafer, pressing the wafer against the upper surface of a working plate for polishing, characterized in that: The pressure head comprises a driving part (1), a main shaft (2), a connecting part (3) and a pressure plate (4) which are connected in sequence; The driving part (1) is used to drive the main shaft (2) to perform lifting movement, thereby driving the connecting part (3) and the pressure plate (4) to perform lifting movement; The connecting portion (3) is connected between the spindle (2) and the pressure plate (4), and the connecting portion (3) has: a connected state in which the pressure plate (4) is connected to the spindle (2) by the gravity of the pressure plate (4) before the pressure plate (4) abuts against the wafer, and a disengaged state in which the pressure plate (4) is disengaged from the spindle (2) by the upward supporting force provided by the working plate when the pressure plate (4) is lowered with the spindle (2) to abut against the wafer; in the connected state, the pressure plate (4) moves up and down together with the spindle (2), and in the disengaged state, the pressure plate (4) does not move up and down together with the spindle (2).

2. A pressure head according to claim 1, characterized in that: The connecting portion (3) comprises a connecting rod (31) and a buffer assembly (32); the connecting rod (31) is fixedly connected to the pressure plate (4); the main shaft (2) is connected to the connecting rod (31) via the buffer assembly (32); the buffer assembly (32) is configured to gradually disengage the pressure plate (4) from the main shaft (2) when the connecting portion (3) switches from the connected state to the disengaged state; when the pressure plate (4) and the main shaft (2) are in the disengaged state, the main shaft (2) does not rotate with the pressure plate (4).

3. A pressure head according to claim 2, characterized in that: The buffer assembly (32) comprises a first buffer member (321) and a second buffer member (322) which are arranged opposite to each other, wherein the first buffer member (321) is fixedly connected to the main shaft (2), and the second buffer member (322) is fixedly connected to the connecting rod (31), and the opposite sides of the first buffer member (321) and the second buffer member (322) form a wedge-shaped structure for preventing the pressure plate (4) from falling.

4. A pressure head according to claim 3, characterized in that: The connecting portion (3) further comprises a connecting cover (33), wherein the connecting cover (33) is fixedly connected to the bottom of the main shaft (2), the bottom of the connecting cover (33) penetrates into the interior of the connecting cover, the first buffer member (321) is fixedly connected to the inner wall of the connecting cover (33), the second buffer member (322) is fixedly connected to the outer wall of the top of the connecting rod (31), the top of the connecting rod (31) extends from the bottom of the connecting cover (33) into the connecting cover (33), and the first buffer member (321) and the second buffer member (322) have opposite sides that are gradually inclined inwards in a top-down direction.

5. A pressure head according to claim 3, characterized in that: The connecting portion (3) further comprises a connecting cover (33), wherein the connecting cover (33) is fixedly connected to the top of the connecting rod (31), the top of the connecting cover (33) penetrates into the interior of the connecting rod, the first buffer member (321) is fixedly connected to the outer wall of the bottom of the main shaft (2), the second buffer member (322) is fixedly connected to the inner wall of the connecting cover (33), the bottom of the main shaft (2) extends from the top of the connecting cover (33) into the connecting cover (33), and the first buffer member (321) and the second buffer member (322) have opposite sides that are inclined surfaces that are gradually inclined outwards in a top-down direction.

6. A pressing head according to any one of claims 1 to 5, characterized in that: It also comprises a counterweight for increasing the downward pressure of the pressure plate (4); the counterweight is arranged above the pressure plate (4); and the counterweight is arranged so that its counterweight can be adjusted.

7. A pressure head according to claim 6, characterized in that: The counterweight component is configured as a plurality of counterweight plates (5), each of the counterweight plates (5) is configured in a semicircular shape, and the plurality of counterweight plates (5) are stacked above the pressure head to form a multi-layer counterweight structure, and the number of counterweight plates (5) in each layer of the counterweight structure is configured as two, and the two counterweight plates (5) are arranged opposite to each other.

8. A pressing head according to claim 6, characterized in that: The pressure head also includes a fixed anti-falling component (6), the anti-falling component (6) includes a key pin (61), the outer wall of the main shaft (2) is provided with a socket (21) that is plugged and adapted to the key pin (61), and the key pin (61) can move horizontally in a direction toward the socket (21) but is restricted in the vertical direction.

9. A pressing head according to claim 8, characterized in that: The anti-falling assembly (6) further comprises a power device (62), wherein the power device (62) is used to drive the key pin (61) to move in a horizontal direction so that the key pin (61) and the main shaft (2) form a plug-in fit.

10. A pressing head according to claim 4 or 5, characterized in that: A main rod (22) is inserted into the interior of the main shaft (2), and the main rod (22) can be slidably connected to the main shaft (2) along the length direction of the main shaft (2); a first air channel (221) is formed in the main rod (22) along its own length direction, and the first air channel (221) passes through both ends of the main rod (22); a second air channel (311) is formed in the connecting rod (31), and the second air channel (311) passes through the top of the connecting rod (31) and is connected to the first air channel (221); an inflation device (7) is connected to the top of the main rod (22), and the inflation device (7) is communicated with the interior of the first air channel (221).

11. A pressing head according to claim 10, characterized in that: A connecting frame (8) is provided between the output end of the driving part (1) and the main shaft (2) for connecting and fixing the two. The connecting frame (8) comprises: A connecting plate (81) is located below the driving unit (1), and an output end of the driving unit (1) is fixedly connected to the connecting plate (81); A movable plate (82) is located below the connecting plate (81), and the main shaft (2) is fixedly connected to the movable plate (82); The support rod (83) is fixedly connected between the connecting plate (81) and the movable plate (82).

12. A pressing head according to claim 11, characterized in that: The pressure head further comprises a main frame (9) for mounting various components, and the main frame (9) comprises: A top plate (91) is arranged above the connecting plate (81), and the body of the driving unit (1) is fixedly mounted on the top plate (91); A bottom plate (92) is arranged between the movable plate (82) and the connecting cover (33); the main shaft (2) passes through the bottom plate (92) and is slidably connected to the bottom plate (92); A guide column (93) is fixedly connected between the top plate (91) and the bottom plate (92); the guide column (93) passes through the movable plate (82) and is slidably connected to the movable plate (82) along its own length direction.

13. A pressing head according to claim 11, characterized in that: A mounting plate (10) is provided between the connecting plate (81) and the inflation device (7); the inflation device (7) is fixedly connected to the mounting plate (10); a guide hole (101) is provided on the mounting plate (10); the support rod (83) passes through the guide hole (101) and is slidably connected to the mounting plate (10).

14. A wafer polishing device, characterized in that: The invention comprises a pressure head as described in any one of claims 1 to 13.

15. The wafer polishing device according to claim 14, characterized in that: Also includes: A working plate, used for grinding the surface of the wafer, the pressing head is located above the working plate, and the pressing head is used for pressing the wafer onto the working plate; A driving device is used to drive the working disk to rotate.

Images