Thinning machine capable of being used for wafer trimming

Abstract

The utility model provides a thinning machine capable of being used for wafer trimming, which comprises a wafer placing platform, a grinding device, a wafer loading device, a positioning device, a cleaning device and a mechanical arm, and is characterized in that a sucker is arranged on the wafer placing platform and is used for sucking and fixing a wafer; the lower end of the wafer placing platform is connected with a moving device to control the wafer placing platform to linearly move relative to the grinding device; the grinding device is located right behind the wafer placing platform and comprises a grinding assembly and a moving assembly. The moving device can drive the wafer placing platform to move below the grinding assembly, and when the edge of the grinding assembly passes through the circle center of the wafer, the thinning machine is in a thinning working state; and when the edge of the grinding assembly is located at the position of the required trimming width of the wafer, the thinning machine is in a trimming working state. According to the utility model, the relative position of the wafer and the grinding wheel is changed, and the rough grinding wheel of the thinning machine is used for trimming, so that the effect of small edge fracture is realized, meanwhile, one machine has multiple functions, the trimming process is completed under the condition that only the thinning machine is arranged, and the cost can be reduced.

Description

Technical Field

[0001] The utility model belongs to the field of semiconductor integrated circuit manufacturing, and in particular relates to a thinning machine that can be used for wafer edge trimming. Background Art

[0002] Wafer bonding, which tightly bonds two wafers together through chemical and physical processes, is a key step in semiconductor manufacturing and plays a crucial role in both MEMS (microelectromechanical systems) and CMOS (complementary metal oxide semiconductor) processes. Wafer bonding is closely related to the edge trimming process. In existing semiconductor processes, to ensure the integrity and smoothness of the wafer edges, the bonded wafers must be trimmed to remove the unbonded area around the wafer to ensure the normal operation of subsequent processes.

[0003] Wafer trimming is typically performed using a trimming machine equipped with a blade that cuts the edge of the wafer. During the cutting process, the blade and wafer are perpendicular, and both rotate, with the blade rotating at high speed and the wafer rotating slowly. Trimming is achieved through continuous processing. During the trimming process, both the cutting speed and blade shape can affect the process, causing cracks in the wafer and leading to wafer edge breakage. Therefore, minimizing edge breakage during the bonded wafer slicing process while reducing equipment development costs is an urgent issue. Utility Model Content

[0004] The present invention is to solve all or part of the problems of the above-mentioned prior art and provides a thinning machine that can be used for wafer trimming. By using the HRG300 thinning machine, the relative position of the wafer and the grinding wheel is modified, and the trimming work is performed by the grinding wheel of the thinning machine so that only the edge of the wafer is cut to complete the trimming process and achieve a process effect with small edge cracks. At the same time, one machine can be used for multiple purposes. The trimming process can be completed with only the thinning machine, which can reduce costs and speed up research and development progress.

[0005] In order to achieve the above-mentioned purpose, the utility model provides a thinning machine that can be used for wafer trimming, including a wafer placing platform and a grinding device, wherein a suction cup is provided on the wafer placing platform, and the suction cup is used to suck and fix the wafer; the lower end of the wafer placing platform is connected to a moving device, which controls the linear movement of the wafer placing platform relative to the grinding device; the grinding device is located directly behind the wafer placing platform, and the grinding device includes a grinding assembly and a moving assembly, the lower end of the moving assembly is fixedly connected to the grinding assembly, and the grinding assembly is rotated around its central axis; the moving device can drive the wafer placing platform to move to the bottom of the grinding assembly, and when the edge of the grinding assembly passes the center of the wafer, the thinning machine is in a thinning working state; when the edge of the grinding assembly is located at the required trimming width of the wafer, the thinning machine is in a wafer trimming working state.

[0006] The thinning machine that can be used for wafer trimming also includes a wafer loading device, a positioning device and a cleaning device. The wafer loading device includes a first wafer loading platform and a second wafer loading platform, which are symmetrically installed on the left front side and the right front side of the wafer placement platform for loading and unloading wafer transfer boxes; the positioning device is located on the left side of the wafer placement platform for confirming the position and direction of the wafer; the cleaning device is located on the right side of the wafer placement platform for cleaning the wafer after grinding.

[0007] The wafer trimming machine further includes a robotic arm, comprising a first robotic arm and a second robotic arm. The first robotic arm is located directly in front of the wafer placement platform, and the second robotic arm is located to the right rear of the wafer placement platform, between the grinding device and the cleaning device. A wafer gripper is provided at the end of each robotic arm for gripping and securing the wafer to ensure stability and safety during movement.

[0008] The wafer placement platform is mounted on the moving device via a rotating device, and the rotation direction of the rotating device is opposite to the rotation direction of the motion component, so as to facilitate efficient trimming work.

[0009] The moving device includes a motor and a connecting rod. The motor controls the movement of the wafer placement platform through the connecting rod, and drives the wafer placement platform to move to a corresponding position below the grinding assembly according to the requirements of thinning or trimming operations.

[0010] The grinding assembly includes a coarse grinding wheel and a fine grinding wheel, both of which are toothed. The coarse grinding wheel and the fine grinding wheel are concentric and connected by screws. The coarse grinding wheel has 2500 mesh straight teeth, while the fine grinding wheel has 8000 mesh straight teeth. During the trimming process, the coarse grinding wheel is used to trim the wafer.

[0011] The grinding device also includes a lifting device, which is connected to the motion component, driving the coarse grinding wheel and the fine grinding wheel to rise and fall together, and adjusting the relative height between the grinding wheel and the wafer according to the corresponding process requirements of thinning or trimming; the motion component drives the coarse grinding wheel and the fine grinding wheel to rotate coaxially, and adjusts the rotation speed according to the process requirements of thinning or trimming.

[0012] The trimming width is set according to process requirements and is generally 2-5 mm.

[0013] The cleaning device includes a cleaning component and a drying component, and cleans the processed wafers through DIW (deionized water) + CDA (compressed dry air).

[0014] Compared with the existing technology, the beneficial effects of the present invention mainly include as follows: The present invention proposes a thinning machine that can be used for wafer trimming. By changing the relative position of the wafer and the grinding wheel, the toothed grinding wheel of the thinning machine is used for trimming, which can reduce the edge cracking caused by trimming. At the same time, the trimming process can be realized with only the thinning machine, which can reduce equipment procurement and meet small-batch trimming needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the specific embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 The utility model provides a schematic diagram of a top view of the thinning machine that can be used for wafer trimming.

[0017] Figure 2 This is a moving trajectory diagram of a wafer placement platform of a thinning machine that can be used for wafer trimming provided by the utility model.

[0018] Figure 3 This is a schematic diagram of the relative positions of a grinding wheel and a wafer in a thinning machine that can be used for wafer trimming provided by the utility model during thinning operation.

[0019] Figure 4 This is a schematic diagram of the relative positions of a grinding wheel and a wafer in a trimming working state of a thinning machine that can be used for wafer trimming provided by the utility model.

[0020] Figure 5 This is a schematic diagram of the trimming effect of a thinning machine that can be used for wafer trimming provided by the utility model. DETAILED DESCRIPTION

[0021] The aforementioned and other technical aspects, features, and functions of the present invention are clearly presented in the following detailed description of a preferred embodiment with reference to the accompanying drawings. Directional terms such as up, down, left, right, front, and back, used in the following embodiments, are merely references to the directions in the accompanying drawings. Therefore, the directional terms used are for illustrative purposes only and are not intended to limit the present invention.

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0023] The utility model provides a thinning machine that can be used for wafer trimming, such as Figure 1 The device includes a wafer placement platform 1, a grinding device 2, a wafer loading device 3, a positioning device 4, a cleaning device 5 and a robotic arm 6.

[0024] Wafer platform 1 is equipped with a suction cup for holding the wafer in place. A moving mechanism is connected to the lower end of platform 1, controlling its linear movement relative to the grinding mechanism. Grinding mechanism 2 is located directly behind platform 1 and comprises a grinding assembly and a motion assembly. The lower end of the motion assembly is fixedly connected to the grinding assembly, causing it to rotate about its central axis. The grinding assembly includes a coarse grinding wheel and a fine grinding wheel, both of which are toothed. The coarse and fine grinding wheels are concentric and connected by screws. The coarse grinding wheel has 2500 mesh straight teeth, while the fine grinding wheel has 8000 mesh straight teeth. The coarse grinding wheel is used to trim the wafer during the trimming process.

[0025] The grinding device also includes a lifting device, which is connected to the motion component to drive the coarse grinding wheel and the fine grinding wheel to rise and fall together, and adjust the relative height between the grinding wheel and the wafer according to the corresponding process requirements of thinning or trimming; the motion component drives the coarse grinding wheel and the fine grinding wheel to rotate coaxially.

[0026] The wafer loading device 3 includes a first wafer loading table and a second wafer loading table, which are symmetrically installed on the left front side and the right front side of the wafer placement platform 1, and are used to load and unload wafer transfer boxes; the positioning device is located on the left side of the wafer placement platform 1, and is used to confirm the position and direction of the wafer; the cleaning device 5 is located on the right side of the wafer placement platform 1, and the cleaning device includes a cleaning component and a drying component. After the wafer is ground, the wafer is cleaned by DIW (deionized water) + CDA (compressed dry air).

[0027] The robotic arm 6 includes a first robotic arm and a second robotic arm. The first robotic arm is located directly in front of the wafer placement platform 1, and the second robotic arm is located to the right rear of the wafer placement platform 1, between the grinding device 2 and the cleaning device 5. A wafer gripper is provided at the end of the robotic arm, which uses vacuum or clamping to fix the wafer to ensure the stability and safety of the wafer during movement.

[0028] The working method of the utility model is as follows: the moving device can drive the wafer placement platform 1 to move to the bottom of the grinding assembly, and the moving trajectory is as follows: Figure 2 As shown, the moving position of the wafer placement platform 1 is determined according to the thinning or trimming operation requirements. Figure 3 As shown, when the edge of the grinding assembly passes the center of the wafer, the thinning machine is in the thinning working state; Figure 4 As shown, when the edge of the grinding assembly is located at the desired trimming width of the wafer, the thinning machine is in the trimming working state, and the trimming width is generally 2-5mm. When performing trimming work, the traditional trimming machine uses a single blade, and the relative speed difference between the blade and the wafer is large (the blade speed is several thousand to tens of thousands of revolutions per minute, and the wafer speed is 1° to 5° per second), resulting in large edge cracks; the thinning machine grinding wheel has multiple toothed blades, the wafer speed is 100 revolutions per minute, and the grinding wheel speed is 1000 revolutions per minute. There are many short non-contact processes during processing, which reduces continuous processing damage and can achieve an edge crack of less than 10μm (such as Figure 5 shown).

[0029] For the sake of clarity, some commonly used English nouns or letters used in this application are only used for illustrative purposes and are not intended to be limiting or specific. Their possible Chinese translations or specific letters should not be used to limit the scope of protection of this application. It should also be noted that, in this article, relational terms such as "first" and "second" are merely used to distinguish one entity or operation from another, and do not necessarily require or imply any actual relationship or order between these entities or operations.

Claims

1. A thinning machine that can be used for wafer trimming, characterized in that: The invention comprises a wafer placement platform (1) and a grinding device (2), wherein a suction cup is provided on the wafer placement platform (1) for sucking and fixing the wafer, and the lower end of the wafer placement platform (1) is connected to a moving device for controlling the linear movement of the wafer placement platform (1) relative to the grinding device (2); the grinding device (2) comprises a grinding component and a motion component, and the lower end of the motion component is fixedly connected to the grinding component and causes the grinding component to rotate around its central axis; the moving device drives the wafer placement platform (1) to move to the bottom of the grinding component, and the edge of the grinding component passes the center of the wafer, and the thinning machine is in a thinning working state; or the edge of the grinding component is located at a position of the required trimming width of the wafer, and the thinning machine is in a trimming working state.

2. A wafer trimming machine according to claim 1, characterized in that: It also includes a wafer loading device (3), a positioning device (4) and a cleaning device (5), wherein the wafer loading device (3) includes a first wafer loading platform and a second wafer loading platform, which are symmetrically installed on the left front side and the right front side of the wafer placement platform (1); the positioning device (4) is located on the left side of the wafer placement platform (1); and the cleaning device (5) is located on the right side of the wafer placement platform (1).

3. A wafer trimming machine according to claim 2, characterized in that: The invention also includes a robot arm (6), wherein the robot arm (6) includes a first robot arm and a second robot arm, wherein the first robot arm is located directly in front of the wafer placement platform (1), and the second robot arm is located to the right rear of the wafer placement platform (1), between the grinding device (2) and the cleaning device (5).

4. A wafer trimming machine according to claim 1, characterized in that: The wafer placement platform (1) is mounted on the moving device via a rotating device, and the rotation direction of the rotating device is opposite to the rotation direction of the moving component.

5. The wafer trimming machine according to claim 1, wherein: The moving device comprises a motor and a connecting rod, and the motor controls the movement of the wafer placement platform (1) through the connecting rod.

6. The wafer trimming machine according to claim 1, wherein: The grinding assembly includes a coarse grinding wheel and a fine grinding wheel, both of which are toothed grinding wheels; the coarse grinding wheel and the fine grinding wheel are concentric structures, and the coarse grinding wheel and the fine grinding wheel are connected by screws.

7. A wafer trimming machine according to claim 6, characterized in that: The coarse grinding wheel has 2500 mesh straight teeth, and the fine grinding wheel has 8000 mesh straight teeth.

8. The wafer trimming machine according to claim 6, characterized in that: The grinding device further comprises a lifting device, which is connected to the motion assembly and drives the coarse grinding wheel and the fine grinding wheel to rise and fall together; the motion assembly drives the coarse grinding wheel and the fine grinding wheel to rotate coaxially.

9. The wafer trimming machine according to claim 1, wherein: The trimming width is generally 2-5 mm.

10. The wafer trimming machine according to claim 2, characterized in that: The cleaning device (5) comprises a cleaning component and a drying component.

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