An adjustable flat single-arm grinder upper disc structure

Abstract

The utility model discloses a one -armed grinder upper disc structure that can adjust flat, including the support frame of bottom connection lower mill disc and be located the drive cylinder on the support frame, and drive cylinder is connected with upper mill disc through connecting component, to drive the up and down displacement of upper mill disc, a plurality of stud are fixedly arranged in the support frame at corresponding upper mill disc center, every stud all has the top pressure nut through the threaded connection, and a plurality of top pressure nuts form the horizontal datum plane coupled with upper mill disc center in common, and horizontal datum plane can keep the levelness of upper mill disc when drive cylinder pulls upper mill disc to the preset height, to solve the problem that the cylinder pulls the grinder upper mill disc and moves up in the prior art and is easy to cause upper mill disc deflection, and then influences the follow -up silicon wafer grinding processing quality.

Description

Technical Field

[0001] This utility model relates to the field of silicon wafer processing technology, specifically to an adjustable leveling single-arm grinding machine upper plate structure. Background Technology

[0002] In the silicon wafer grinding process, the relative positional accuracy and motion stability of the upper and lower grinding discs of the grinding machine directly affect the grinding quality of the silicon wafer. Currently, the upper grinding disc of a silicon wafer grinding machine is usually connected to the drive cylinder via a spherical bearing. The self-aligning function of the spherical bearing is used to achieve flexible contact between the upper and lower grinding discs, in order to compensate for installation errors, processing errors, and posture deviations during the grinding process, and ensure uniform distribution of grinding pressure.

[0003] However, in actual operation, when the cylinder drives the upper grinding disc to rise, and it is disengaged from the lower grinding disc after the grinding process is completed or its position is adjusted, the upper grinding disc is prone to accidental collision with the support structure at the top of the equipment. Since the upper grinding disc is only connected to the cylinder through a spherical bearing and lacks a rigid limiting structure, the impact force generated by the collision will cause the upper grinding disc to deflect unexpectedly under the support of the spherical bearing, thus disrupting the original horizontal state of the upper grinding disc.

[0004] This deflection not only causes the upper grinding disc to fail to maintain the preset parallelism when it descends again and contacts the lower grinding disc, increasing the risk of direct collision between the upper and lower grinding discs and causing damage to the grinding disc or silicon wafer; it also significantly affects the stability of the gap between the upper and lower grinding discs. In the subsequent process of adjusting the gap by pushing the silicon wafer, the deflected upper grinding disc will cause uneven gap distribution, and problems such as jamming and pressure fluctuations are likely to occur during the adjustment process, thereby reducing the flatness and parallelism accuracy of silicon wafer grinding and increasing the product defect rate. Utility Model Content

[0005] The purpose of this invention is to solve the problem that the upper grinding disc of a grinding machine is easily deflected during the process of the cylinder pulling the upper grinding disc upward, which affects the quality of subsequent silicon wafer grinding. This invention provides an adjustable leveling upper disc structure for a single-arm grinding machine.

[0006] To address the shortcomings of the aforementioned technical problems, the present invention adopts the following technical solution: an adjustable leveling single-arm grinding machine upper plate structure, comprising a support frame with the bottom connected to the lower grinding plate and a drive cylinder mounted on the support frame. The drive cylinder is connected to the upper grinding plate through a connecting component to drive the upper grinding plate to move up and down. The support frame has multiple studs fixedly mounted at the center of the corresponding upper grinding plate. Each stud is connected to a top pressure nut by a thread. Multiple top pressure nuts together form a horizontal reference plane coupled with the center of the upper grinding disc. The horizontal reference plane can maintain the levelness of the upper grinding disc when the drive cylinder pulls the upper grinding disc to a preset height.

[0007] As a further optimization of the upper platen structure of the adjustable single-arm grinding machine of this utility model: the support frame is provided with four symmetrically distributed studs, and the center of the symmetrical distribution of the four studs coincides with the center of the upper grinding plate.

[0008] As a further optimization of the upper platen structure of the adjustable single-arm grinding machine of this utility model: an elastic layer is provided on the side of the top pressure nut facing the lower grinding plate.

[0009] As a further optimization of the upper platen structure of the adjustable single-arm grinding machine of this utility model: each stud is threaded with two top-pressure nuts, and the two top-pressure nuts can be tightened in opposite directions to form a tight top pressure, thereby increasing the frictional resistance between the top-pressure nuts and the stud.

[0010] As a further optimization of the upper platen structure of the adjustable single-arm grinding machine of this utility model: an anti-loosening washer is provided between the two top pressure nuts.

[0011] As a further optimization of the upper plate structure of the adjustable single-arm grinding machine of this utility model: the connecting component is a spherical bearing, the outer ring of the spherical bearing is fixedly connected to the connecting flange provided at the end of the piston rod of the drive cylinder by bolts, a positioning pin is installed between the connecting flange and the outer ring of the spherical bearing, and the inner ring of the spherical bearing is interference-fitted with a connecting seat, and the upper grinding plate is fixedly connected to the bottom of the connecting seat.

[0012] As a further optimization of the adjustable single-arm grinding machine upper plate structure of this utility model: the outer surface of the inner ring and the inner surface of the outer ring of the connecting component are both precision-machined spherical surfaces, and the radii of curvature of the two spherical surfaces are matched. The spherical contact area of ​​the joint bearing of the connecting component is filled with high-temperature grease.

[0013] As a further optimization of the upper platen structure of the adjustable single-arm grinding machine of this utility model: a grease injection hole is opened on the outer side of the connecting component, a dustproof screw plug is installed in the grease injection hole, and the grease injection hole is connected to the spherical contact area of ​​the connecting component.

[0014] Compared with the prior art, the present invention has the following beneficial effects: This invention utilizes studs symmetrically distributed at four points to engage with a top-pressure nut. When the drive cylinder dynamically moves the upper grinding disc upwards, the orientation of the upper grinding disc can be adjusted to a horizontal state. After adjusting the preset parallelism of the upper grinding disc, the probability of excessive deflection when the drive cylinder moves the upper grinding disc downwards is reduced, thereby decreasing the possibility of collision damage to the silicon wafer or lower grinding disc due to excessive deflection during the downward movement of the upper grinding disc. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the present invention in its raised state; Figure 2 This is a schematic diagram of the structure of the present invention in the grinding state; Figure 3 This is a cross-sectional structural diagram of the present invention in its raised state; The markings in the diagram are: 1. Support frame; 2. Grinding layer; 3. Injection pipe; 4. Upper grinding disc; 5. Drive cylinder; 6. Stud; 7. Top pressure nut; 8. Connecting assembly. Detailed Implementation

[0016] To better understand this utility model, the following embodiments further illustrate the content of this utility model, but the content of this utility model is not limited to the following embodiments.

[0017] The relative positional accuracy and motion stability of the upper and lower grinding discs in a grinding machine are core factors determining the grinding quality of silicon wafers. They directly affect key indicators such as the flatness and parallelism of the silicon wafers, and consequently, the manufacturing precision and performance of subsequent semiconductor devices. To achieve high-quality grinding, grinding machines typically employ specific structures to ensure the coordinated operation of the upper and lower grinding discs.

[0018] like Figure 1-3 As shown, an adjustable single-arm grinding machine upper plate structure includes a support frame 1, on which a drive cylinder 5 is mounted. The drive cylinder 5 is connected to an upper grinding plate 4 via a connecting component 8, while a lower grinding plate is fixed to the support frame 1. In the silicon wafer processing step, the drive cylinder 5 drives the upper grinding plate 4 downwards, cooperating with the lower grinding plate. Subsequently, the lower grinding plate rotates stably under the drive of a dedicated drive structure. The upper and lower grinding plates work together to complete the grinding process on the silicon wafer. To further improve the working performance of the upper grinding plate 4, a dedicated grinding layer 2 for grinding silicon wafers is provided at the bottom of the upper grinding plate 4, ensuring the stability of the grinding process. Simultaneously, multiple liquid injection pipes 3 are evenly distributed within the upper grinding plate 4. These liquid injection pipes 3 cooperate with the evenly distributed grooves of the grinding liquid in the grinding layer 2. During the grinding process, on the one hand, they can wash away the particles generated during grinding on the silicon wafer, preventing particle residue from affecting the grinding accuracy; on the other hand, they can reduce the temperature during the grinding process, preventing high temperatures from adversely affecting the silicon wafer performance and grinding quality.

[0019] Regarding the selection of the connecting component 8, most silicon wafer polishing machines currently use spherical bearings as the connecting part between the drive cylinder 5 and the upper polishing disc 4. Some equipment may also use other structures with corresponding functions according to actual needs. Spherical bearings, with their unique self-aligning function, can achieve flexible contact between the upper and lower polishing discs 4 and 5, effectively compensating for installation errors during equipment installation, machining errors during component processing, and possible posture deviations of the upper polishing disc 4 during polishing. This ensures that the polishing pressure is evenly distributed on the silicon wafer surface, providing a fundamental guarantee for high-quality polishing of the silicon wafer. However, in actual operation, the connecting structure with spherical bearings as its core has certain problems: when the cylinder drives the upper polishing disc 4 upward, if the polishing process is completed and the upper polishing disc 4 detaches from the lower polishing disc, or if the position of the upper polishing disc 4 needs to be adjusted, the upper polishing disc 4 is very prone to accidental collision with the support structure at the top of the equipment. Since the upper grinding disc 4 is only connected to the cylinder through a spherical bearing and lacks a rigid limiting structure to constrain its movement, the impact force generated by the collision will cause the upper grinding disc 4 to deflect unexpectedly under the support of the spherical bearing. This deflection directly destroys the original horizontal state of the upper grinding disc 4, bringing a series of serious problems to the subsequent grinding work.

[0020] To achieve precise control of the horizontal attitude of the upper grinding disc 4 and ensure the coordinated accuracy of the upper and lower grinding discs during silicon wafer grinding, four symmetrically arranged studs 6 are fixedly installed on the support frame 1 at the center of the upper grinding disc 4. Each stud 6 is connected to a top-pressure nut 7 via threaded engagement. The cooperation between the four studs 6 and the top-pressure nut 7 serves both as attitude calibration under dynamic conditions and as a reliable adjustment path for static debugging. From the perspective of the upward movement of the upper grinding disc 4 under dynamic conditions, when the drive cylinder 5 drives the upper grinding disc 4 upward through the connecting component 8 to separate it from the lower grinding disc and create conditions for silicon wafer loading, the top-pressure nut 7 will form a tight top-pressure contact with the central area of ​​the connecting component 8. At this time, the axial impact force generated by the drive cylinder 5 driving the upper grinding disc 4 will be transmitted to the four symmetrically distributed top-pressure nuts 7 through the connecting component 8. The four top-pressure nuts 7 will generate a reverse supporting force, creating a four-point top-pressure effect on the connecting component 8 and the upper grinding disc 4. The four-point pressure effectively counteracts the tilting tendency that may occur in the upper grinding disc 4 during its vertical ascent due to inertia, slight deformation of the connecting components 8, or uneven force. This keeps the attitude deviation of the upper grinding disc 4 within a minimal range, thus helping it maintain good flatness throughout the ascent and preventing inaccurate positioning of the subsequent silicon wafer loading due to upward attitude shift, or affecting the initial alignment accuracy of the upper and lower grinding discs during subsequent grinding. An elastic layer made of rubber is fixed to one side of the pressure nut 7 facing the center of the upper grinding disc 4 to reduce the impact force of the pressure nut 7 colliding with the upper grinding disc 4, thus providing a buffer to reduce damage to both the pressure nut 7 and the upper grinding disc 4, while also preventing rotational displacement of the pressure nut 7.

[0021] In static debugging and daily use scenarios, operators can use tools to rotate the top pressure nuts 7 on the four studs 6. Utilizing the precise adjustment characteristics of the threaded drive, the relative height position of the top pressure nuts 7 on the studs 6 can be changed by rotation. Specifically, rotating the top pressure nuts 7 clockwise moves them downwards along the studs 6, while rotating them counterclockwise moves them upwards. Since the four top pressure nuts 7 correspond to the four key support points of the upper grinding disc 4 connecting assembly 8, fine-tuning the height of one or more top pressure nuts 7 can transmit force to the upper grinding disc 4 through the connecting assembly 8, causing the upper grinding disc 4 to make a slight angular adjustment around the horizontal axis. The adjustable settings of the four studs 6 and top pressure nuts 7 enable precise and stable control of the horizontality of the upper grinding disc 4, ensuring that the upper grinding disc 4 and the lower grinding disc achieve the preset parallelism requirements before grinding. This lays the foundation for uniform pressure distribution and stable accuracy during subsequent silicon wafer grinding, further optimizing the working posture of the upper grinding disc 4 and reducing the risk of grinding defects caused by posture deviations.

[0022] To cope with complex working conditions such as equipment vibration and accidental collisions during grinding, a second top-pressure nut 7 can be added to a single stud 6, forming a double-nut locking structure. When the two top-pressure nuts 7 are tightened in opposite directions to achieve tight pressure, on the one hand, the contact surfaces of the two top-pressure nuts 7 will generate a large static friction force; on the other hand, the threaded meshing surfaces of the top-pressure nuts 7 and the stud 6 will increase the normal pressure due to the additional axial pressure, thereby increasing the frictional resistance between the threaded pairs. The dual friction effect of the two top-pressure nuts 7 can significantly improve the anti-loosening ability of the top-pressure nuts 7. Specifically, when the top-pressure nuts 7 are impacted or vibrated by the upper grinding disc 4, they can effectively resist the rotational tendency of the top-pressure nuts 7 themselves, preventing a single top-pressure nut 7 from loosening or shifting position due to vibration. This ensures that the supporting position of the top-pressure nuts 7 on the connecting component 8 is stable, maintaining the consistency of the horizontal posture of the upper grinding disc 4 over a long period of time, and avoiding the impact of posture deviation caused by changes in the position of the top-pressure nuts 7 on the grinding accuracy. Additionally, anti-loosening washers can be installed between the two top-pressure nuts 7 on a single stud 6, thereby further reducing the probability of the top-pressure nuts 7 shifting due to impact, thus maintaining the horizontal stability of the horizontal reference plane formed by multiple top-pressure nuts 7.

[0023] When the drive cylinder 5 moves the calibrated horizontally oriented upper grinding disc 4 downwards, its own weight forms a passive stabilization mechanism. Once the upper grinding disc 4 contacts the connecting component 8, its gravity exerts a continuous and uniform top pressure on the connecting component 8. This top pressure restricts the degrees of freedom of the connecting component 8, effectively suppressing any attitude deviation that might occur during descent due to fluctuations in the cylinder's driving force or minor deformations of the connecting component 8. Simultaneously, the gravity of the upper grinding disc 4, acting as a constant load, balances the downward driving force of the drive cylinder 5, ensuring a uniform and stable movement of the upper grinding disc 4 during descent. This further guarantees the stability of its relative attitude, ensuring precise contact and uniform application of grinding pressure between the upper and lower grinding discs.

[0024] The connecting component 8 is a spherical plain bearing. As the core connecting component between the drive cylinder 5 and the upper grinding disc 4 in the silicon wafer polishing machine, the spherical plain bearing's connection structure must balance flexible self-aligning function and stable force transmission requirements. Specifically, the piston rod end of the drive cylinder 5 is equipped with a connecting flange, which is fixedly connected to the outer ring of the spherical plain bearing by bolts. A locating pin is installed between the two to achieve circumferential limitation and prevent relative rotation. The inner ring of the spherical plain bearing is assembled with the connecting seat on the top of the upper grinding disc 4 by interference fit. The bottom of the connecting seat is connected to the body of the upper grinding disc 4 by welding or bolt fastening, forming a complete force transmission path. The outer surface of the inner ring and the inner surface of the outer ring of the spherical plain bearing are both precision-machined spherical surfaces with matched radii of curvature, ensuring that the two can achieve flexible relative rotation within a 360° range, meeting the posture adjustment requirements of the upper grinding disc 4 during the polishing process. To reduce the coefficient of friction, reduce wear, and improve self-aligning sensitivity, the spherical contact area is filled with high-temperature grease. A grease injection hole is provided on the side of the outer ring for periodic replenishment, and the grease injection hole is equipped with a dustproof plug to prevent impurities from entering. Meanwhile, annular retaining rings are installed at the upper and lower ends of the inner ring of the spherical plain bearing. The retaining rings are fixed to the stepped surface of the connecting seat by screws. Their inner diameter is slightly smaller than the outer diameter of the outer ring of the spherical plain bearing, which can limit the axial displacement of the outer ring and prevent the outer ring from axially separating from the inner ring during up and down movement. Skeleton-type rubber sealing rings are installed at the fit clearances between the outer ring and the connecting flange, and between the inner ring and the connecting seat, forming a double sealing barrier to prevent silicon powder particles, grinding fluid and external dust from entering the bearing.

[0025] Based on this, the structure can be further refined: a disc spring is added between the outer ring of the spherical bearing and the connecting flange. The spring compression is changed by adjusting the tightening torque of the connecting flange bolts, and an adjustable preload is applied to the spherical contact to eliminate gaps and improve attitude response speed, adapting to different grinding pressure conditions; an arc-shaped limiting block is set on the outer side of the outer ring of the spherical bearing and fixedly connected to the connecting flange. A boss is set at the corresponding position on the outer side of the inner ring. By limiting the rotation angle of the boss, the upper grinding disc 4 is prevented from excessive deflection due to accidental collision, protecting the bearing from damage. A miniature temperature sensor is embedded inside the outer ring of the spherical plain bearing and connected to the equipment control system via wires to monitor the operating temperature in real time. It automatically alarms when the temperature exceeds a preset threshold, facilitating timely maintenance. The inner ring of the spherical plain bearing is designed as a replaceable, split structure, consisting of a base and a wear-resistant bushing. The bushing is made of high-hardness alloy material and undergoes surface hardening treatment. It is connected to the base by bolts and can be replaced separately after wear. A locating pin ensures concentricity accuracy. At the interference fit between the inner ring of the spherical plain bearing and the connecting seat, a radially penetrating set screw is installed, with its end embedded in the annular groove of the connecting seat. This enhances the connection strength and serves as an auxiliary safety measure for the axial retaining ring, preventing long-term vibration from causing fit failure.

[0026] Specifically, the connecting component 8 can also be other corresponding structures to maintain the structural function of the upper grinding disc 4. The specific structure, model, and operation of the connecting component 8 should be understood as prior art.

[0027] The specific embodiments of this utility model have been described above. It should be understood that this utility model is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the substantive content of this utility model.

Claims

1. An adjustable leveling single-arm grinding machine upper plate structure, comprising a support frame (1) with the bottom connected to the lower grinding plate and a drive cylinder (5) disposed on the support frame (1), the drive cylinder (5) being connected to the upper grinding plate (4) via a connecting assembly (8) to drive the upper grinding plate (4) to move up and down, characterized in that: The support frame (1) has multiple studs (6) fixedly installed at the center of the corresponding upper grinding disc (4); Each stud (6) is connected to a top pressure nut (7) by a thread. Multiple top pressure nuts (7) together form a horizontal reference plane coupled with the center of the upper grinding disc (4). The horizontal reference plane can maintain the levelness of the upper grinding disc (4) when the drive cylinder (5) pulls the upper grinding disc (4) to a preset height.

2. The adjustable leveling upper platen structure of a single-arm grinding machine as described in claim 1, characterized in that: The support frame (1) is provided with four symmetrically distributed studs (6), and the center of the symmetrical distribution of the four studs (6) coincides with the center of the upper grinding disc (4).

3. The adjustable leveling upper platen structure of a single-arm grinding machine as described in claim 1, characterized in that: The top pressure nut (7) has an elastic layer on the side facing the lower grinding disc.

4. The adjustable leveling upper platen structure of a single-arm grinding machine as described in claim 1, characterized in that: Each stud (6) is threaded with two top-pressure nuts (7). The two top-pressure nuts (7) can be tightened in opposite directions to form a tight top pressure, thereby increasing the frictional resistance between the top-pressure nuts (7) and the stud (6).

5. The adjustable leveling upper platen structure of a single-arm grinding machine as described in claim 4, characterized in that: An anti-loosening washer is provided between the two top-pressure nuts (7).

6. The adjustable leveling upper platen structure of a single-arm grinding machine as described in claim 1, characterized in that: The connecting component (8) is a spherical bearing. The outer ring of the spherical bearing is fixedly connected to the connecting flange at the end of the piston rod of the drive cylinder by bolts. A positioning pin is installed between the connecting flange and the outer ring of the spherical bearing. The inner ring of the spherical bearing is interference-fitted with a connecting seat, and the upper grinding disc (4) is fixedly connected to the bottom of the connecting seat.

7. The adjustable leveling upper platen structure of a single-arm grinding machine as described in claim 6, characterized in that: The inner ring outer surface and the outer ring inner surface of the connecting component (8) are both precision machined spherical surfaces, and the radii of curvature of the two spherical surfaces are matched. The spherical contact area of ​​the spherical bearing of the connecting component (8) is filled with high-temperature grease.

8. The adjustable leveling upper platen structure of a single-arm grinding machine as described in claim 6, characterized in that: The outer ring side of the connecting component (8) is provided with a grease injection hole, and a dustproof screw plug is installed in the grease injection hole. The grease injection hole is connected to the spherical contact area of ​​the connecting component (8).

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