Precise air motorized spindle for wafer chamfer cutting

Abstract

The invention provides a precise air motorized spindle for wafer chamfer cutting. The precise air motorized spindle comprises a spindle rotor, a driving motor, a front air bearing, a rear air bearing, a cooling water jacket, a rear thrust bearing, a front cover, a rear cover and a shell sleeve. The main shaft rotor is installed in the driving motor, the front end and the rear end of the main shaft rotor are sleeved with the front air bearing and the rear air bearing respectively, the cooling water sleeve is arranged on the outer sides of the front air bearing, the driving motor and the rear air bearing in a sleeving mode, and the rear thrust bearing is located on the outer side of a flying disc of the main shaft rotor. The front cover and the rear cover are located on the front side of the front air bearing and the rear side of the rear thrust bearing respectively and installed on the cooling water jacket, and the outer side of the cooling water jacket is sleeved with the shell sleeve. According to the precise air motorized spindle, the problems that a traditional wafer chamfering machine is insufficient in precision, large in vibration, fast in abrasion and the like are solved, the reliability of the whole system is improved, the service life of the whole system is prolonged, and a more efficient and more precise solution is provided for the semiconductor manufacturing industry.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor manufacturing equipment, and in particular to a precision air electric spindle for wafer chamfering. Background Art

[0002] Wafer chamfering is a key process step in the semiconductor manufacturing process. It is used to remove burrs and sharp corners on the edge of the wafer, making the edge of the wafer smooth and preventing cracks and breakage that may occur in subsequent processing, thereby improving the yield and reliability of the product. With the increasing application of third-generation semiconductor materials (such as silicon carbide SiC), these materials have put forward higher requirements on processing equipment due to their high hardness characteristics. The spindle device of the traditional wafer chamfering machine has the following problems: 1. Insufficient precision: Traditional mechanical bearings are prone to wear after long-term use, resulting in reduced spindle rotation accuracy.

[0003] 2. Large vibration: The friction generated by mechanical contact bearings when rotating at high speed will cause vibration and affect the processing accuracy.

[0004] 3. Fast wear: When mechanical bearings are subjected to high loads, especially when facing high hardness materials, the wear rate is accelerated, which reduces the service life.

[0005] 4. Poor thermal stability: During high-intensity cutting, the spindle assembly will generate a lot of heat. If the heat dissipation is poor, it will cause thermal deformation, which will affect the processing accuracy.

[0006] Therefore, the prior art has deficiencies and needs further improvement. Summary of the invention

[0007] In view of the problems existing in the prior art, the present invention provides a precision air electric spindle for wafer chamfering.

[0008] To achieve the above object, the specific scheme of the present invention is as follows: The present invention provides a precision air electric spindle for wafer chamfering, comprising: Spindle rotor, drive motor, front air bearing, rear air bearing, cooling water jacket, rear thrust bearing, front cover, rear cover, outer shell; The spindle rotor is installed in the drive motor, the front end and the rear end of the spindle rotor are respectively sleeved with a front air bearing and a rear air bearing, the cooling water jacket is sleeved on the outside of the front air bearing, the drive motor and the rear air bearing, the rear thrust bearing is located on the outside of the spindle rotor flying disc, the front cover and the rear cover are respectively located on the front side of the front air bearing and the rear side of the rear thrust bearing and are installed on the cooling water jacket, and the outer shell is sleeved on the outside of the cooling water jacket; The outer side of the cooling water jacket is provided with a plurality of grooves, which form cooling water channels for cooling; An air path is provided through the rear cover, the rear thrust bearing, the rear air bearing, and the cooling water jacket; A plurality of first air holes are arranged on the side of the rear thrust bearing facing the main shaft rotor flying disc, the first air holes are connected to the air path, and the first air holes blow air toward the main shaft rotor flying disc to form air suspension between the rear thrust bearing and the main shaft rotor; The inner diameter surfaces of the front air bearing and the rear air bearing are evenly provided with a plurality of second air holes, which are connected to the air path and blow air toward the spindle rotor to form air suspension between the front air bearing, the rear air bearing and the spindle rotor.

[0009] Furthermore, the rear cover is provided with an air inlet, an air outlet, a cooling water inlet, a cooling water outlet, and a motor line interface; The air inlet is used to transport gas into the air path, and the gas in the air path is discharged through the first air hole and the second air hole and then discharged through the air outlet; The cooling water inlet is used to input cooling water into the cooling water circuit, and then discharge it from the cooling water outlet; The motor line interface is used to connect the drive motor.

[0010] Furthermore, a muffler is also provided on the air outlet.

[0011] Furthermore, a throttle is disposed in each of the first air hole and the second air hole.

[0012] Furthermore, a shaft sleeve is provided between the front air bearing and the main shaft rotor for fixing the position of the driving motor on the main shaft rotor.

[0013] Furthermore, small hole throttling, porous throttling, or slit throttling is arranged between the rear thrust bearing and the main shaft rotor flying disc, between the rear air bearing and the main shaft rotor, and between the front air bearing and the main shaft rotor for blowing air to form air suspension.

[0014] Furthermore, a grinding wheel cutter is mounted on the front end of the spindle rotor via a fastening screw.

[0015] Furthermore, a conical surface is provided at the front end of the spindle rotor, and the grinding wheel cutter disc and the spindle rotor are connected and matched via the conical surface.

[0016] Furthermore, the front air bearing and the rear air bearing are L-shaped.

[0017] Furthermore, the spindle rotor is made of high-strength and high-rigidity materials (including steel, precipitation-hardened ultra-high-strength stainless steel), and the surface is coated with a nano-coating to increase the vibration resistance and wear resistance of the spindle rotor.

[0018] The technical solution of the present invention has the following beneficial effects: 1. Improve rotation accuracy and stability: The air bearing technology (including front air bearing, rear air bearing and rear thrust bearing) is adopted to provide suspension force through high-pressure gas to achieve contactless and frictionless rotation, thereby significantly improving the rotation accuracy and operation stability of the spindle.

[0019] The “L” type air bearing design provides better radial and axial load capacity, further enhancing the rigidity and stability of the spindle.

[0020] 2. Optimize thermal management: The cooling water jacket is provided with a cooling water channel, which can effectively take away the heat generated during the processing, keep the temperature of the spindle assembly stable during operation, reduce thermal deformation caused by temperature changes, and ensure high precision during long-term operation.

[0021] An efficient heat dissipation system helps extend the life of the equipment and ensure consistent processing quality.

[0022] 3. Reduce noise pollution: The air outlet is equipped with a muffler, which effectively reduces the noise generated during gas discharge, improves the working environment, and reduces the impact of noise on operators.

[0023] 4. Enhance structural strength and wear resistance: The spindle rotor is made of high-strength, high-rigidity materials (such as steel or precipitation-hardened ultra-high-strength stainless steel) and coated with a nano-coating, which improves the vibration resistance and wear resistance of the spindle, making it more suitable for processing high-hardness materials such as third-generation semiconductor materials.

[0024] 5. Compact design and efficient power transmission: The drive motor is arranged in the middle of the spindle, which makes the entire spindle structure more compact and better supports the rotation of the spindle, thereby increasing the spindle's bearing power and improving work efficiency.

[0025] The position of the drive motor is fixed by the shaft sleeve to ensure the stability and reliability of power transmission.

[0026] 6. Accurate grinding wheel cutter installation: The grinding wheel cutter is installed on the front end of the spindle rotor through fastening screws and conical surface connection, which ensures the close connection between the grinding wheel cutter and the spindle and improves the positioning accuracy during the cutting process.

[0027] 7.Easy to maintain and use: It is designed with air inlet, air outlet, cooling water inlet, cooling water outlet and motor line interface to facilitate daily maintenance and operation and simplify the use process of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a cross-sectional view of the present invention; Figure 2 is a three-dimensional view of the present invention after removing the outer shell; Figure 3 is a stereogram of the rear air bearing of the present invention; Figure 4 It is a schematic diagram of the installation of the spindle rotor and the grinding wheel cutter disc of the present invention; Figure 5 It is a perspective view of the present invention.

[0029] In the figure: 1. Rear cover; 2. Rear air bearing; 3. Spindle rotor; 4. Cooling water jacket; 5. Drive motor; 6. Front air bearing; 7. Front cover; 8. Air circuit; 9. Rear thrust bearing; 10. Small hole throttle; 11. Outer shell; 12. Bushing; 13. Grinding wheel cutter; 14. Fastening screws; 15. Cooling water circuit; 16. Muffler; 17. Air inlet; 18. Air outlet; 19. Cooling water inlet; 20. Cooling water outlet; 21. Motor line interface; 22. Spindle rotor flying disc;. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments; it can be understood that the specific embodiments described herein are only used to explain the present invention rather than to limit the present invention; it should also be noted that, for ease of description, only the parts related to the present invention rather than all are shown in the accompanying drawings.

[0031] Combination Figure 1-Figure 5 As shown, the present invention provides a precision air electric spindle for wafer chamfering, comprising: a spindle rotor 3, a drive motor 5, a front air bearing 6, a rear air bearing 2, a cooling water jacket 4, a rear thrust bearing 9, a front cover 7, a rear cover 1, and an outer shell 11; The spindle rotor 3 is installed in the drive motor 5. The front and rear ends of the spindle rotor 3 are respectively sleeved with a front air bearing 6 and a rear air bearing 2. The cooling water jacket 4 is sleeved on the outside of the front air bearing 6, the drive motor 5 and the rear air bearing 2. The rear thrust bearing 9 is located on the outside of the spindle rotor flying disc 22. The front cover 7 and the rear cover 1 are respectively located on the front side of the front air bearing 6 and the rear side of the rear thrust bearing 9 and are installed on the cooling water jacket 4. The outer shell 11 is sleeved on the outside of the cooling water jacket 4. The outer side of the cooling water jacket 4 is provided with a plurality of grooves, and the grooves form a cooling water channel 15 for cooling; An air path 8 is provided through the rear cover 1, the rear thrust bearing 9, the rear air bearing 2, and the cooling water jacket 4; A plurality of first air holes are arranged on the side of the rear thrust bearing 9 facing the main shaft rotor flying disc 22, the first air holes are connected to the air path 8, and the first air holes blow air toward the main shaft rotor flying disc 22 to form air suspension between the rear thrust bearing 9 and the main shaft rotor flying disc 22; The inner diameter surfaces of the front air bearing 6 and the rear air bearing 2 are evenly provided with a plurality of second air holes, which are connected to the air path 8 . The second air holes blow air toward the spindle rotor 3 to form air suspension between the front air bearing 6 , the rear air bearing 2 and the spindle rotor 3 .

[0032] The rear cover 1 is provided with an air inlet 17, an air outlet 18, a cooling water inlet 19, a cooling water outlet 20, and a motor line interface 21; The air inlet 17 is used to deliver gas to the air path 8, and the gas in the air path 8 is discharged through the first air hole and the second air hole and then discharged through the air outlet 18; The cooling water inlet 19 is used to input cooling water into the cooling water path 15, and then discharge it from the cooling water outlet 20; The motor line interface 21 is used to connect the drive motor 5 .

[0033] The air outlet 18 is also provided with a muffler 16 .

[0034] A throttle 10 is disposed in each of the first air hole and the second air hole.

[0035] A shaft sleeve 12 is further provided between the front air bearing 6 and the main shaft rotor 3 to fix the position of the driving motor 5 on the main shaft rotor 3 .

[0036] Small hole throttling, porous throttling, or slit throttling are arranged between the rear thrust bearing 9 and the spindle rotor flying disc 22, between the rear air bearing 2 and the spindle rotor 3, and between the front air bearing 6 and the spindle rotor 3 for blowing air to form air suspension.

[0037] A grinding wheel cutter 13 is also mounted on the front end of the spindle rotor 3 via a fastening screw 14 .

[0038] The front end of the spindle rotor 3 is also provided with a conical surface, and the grinding wheel cutter head 13 and the spindle rotor 3 are connected and matched via the conical surface.

[0039] The front air bearing 6 and the rear air bearing 2 are L-shaped.

[0040] The spindle rotor 3 is made of high-strength and high-rigidity materials (including steel, precipitation-hardened ultra-high-strength stainless steel), and is coated with a nano-coating on the surface to increase the vibration resistance and wear resistance of the spindle rotor 3 .

[0041] Working principle of the present invention: 1. Spindle rotor 3 and drive motor 5 The spindle rotor 3 is installed in the drive motor 5, and the rotational power is provided by the drive motor 5. The drive motor 5 is arranged in the middle position of the spindle, which contributes to a compact design and increases the load-bearing capacity.

[0042] 2. Air bearing system The front air bearing 6 and the rear air bearing 2 are respectively sleeved on the front and rear ends of the main shaft rotor 3. These bearings adopt an "L"-shaped design to provide stable support in radial and axial directions.

[0043] The rear thrust bearing 9 is located outside the rear air bearing 2 for additional axial support.

[0044] The cooling water jacket 4 is sleeved on the outside of the front air bearing 6, the drive motor 5 and the rear air bearing 2, and second air holes are arranged on the inner diameter surface thereof, and these air holes are connected to the air path 8 running through the entire assembly.

[0045] The rear cover 1 is provided with first air holes, which are also connected to the air path 8. When high-pressure gas enters the air path 8 through the air inlet 17, it will be ejected from the first air holes and the second air holes to form an air suspension layer between the rear cover 1 and the rear thrust bearing 9 and between the front air bearing 6, the rear air bearing 2 and the cooling water jacket 4, thereby achieving frictionless high-speed rotation.

[0046] 3. Cooling system The outer side of the cooling water jacket 4 is provided with grooves to form a cooling water path 15. Cooling water enters through the cooling water inlet 19, flows through the cooling water path 15, takes away the heat generated by the drive motor 5 and the bearing, and then is discharged from the cooling water outlet 20 to ensure that the spindle assembly maintains a stable temperature during operation.

[0047] 4. Gas circulation and silencer The high-pressure gas enters the gas path 8 from the gas inlet 17, blows out through the first and second gas holes, and finally is discharged through the gas outlet 18. The gas outlet 18 is equipped with a muffler to reduce the noise generated when the gas is discharged and improve the working environment.

[0048] 5. Installation of grinding wheel cutter 13 The front end of the spindle rotor 3 is mounted with a grinding wheel cutter 13 via a fastening screw 14 , and the two are connected and matched via a conical surface, thereby ensuring accurate installation and stable operation of the grinding wheel cutter 13 .

[0049] 6. Materials and surface treatment The spindle rotor 3 is made of a high-strength, high-rigidity material (such as steel or precipitation-hardened ultra-high-strength stainless steel), and is coated with a nano-coating on the surface to improve vibration resistance and wear resistance.

[0050] 7. Comprehensive Effect Through the above design, the precision air electric spindle achieves frictionless high-speed rotation, improving the accuracy and efficiency of wafer chamfering. At the same time, the efficient cooling system ensures long-term working stability, while the air bearing design significantly reduces vibration and wear, extending the service life of the equipment.

[0051] Embodiment 1: A precision air electric spindle for wafer chamfering in the embodiments shown in Figures 1-5. The precision air electric spindle for wafer chamfering has: a protective housing assembly, including a rear cover 1 at the tail end, an outer housing sleeve 11, a cooling water jacket 4 for arranging a cooling water circuit 15, and a front cover 7 at the front end, a spindle rotor 3 with a grinding wheel cutter 13 for cutting installed at the end, an "L"-shaped air bearing assembly arranged at both ends of the spindle to make the spindle stably suspended without friction, including a front air bearing 6, a rear air bearing 2 and a rear thrust bearing 9, and a driving motor 5 for driving the end grinding wheel cutting, which is arranged in the middle of the spindle to increase the spindle load. The housing assembly is provided with a cooling water circuit 15 for cooling and a gas circuit 8 for introducing high-pressure gas.

[0052] like Figure 1 The structural cross-sectional view of the precision air spindle shown in the figure shows that an "L"-shaped air bearing assembly is arranged at both ends of the spindle, including a rear thrust bearing 9 located at the tail end face of the spindle rotor 3, a rear air bearing 2 at the tail end, and a front air bearing 6 located at the front end. The high-pressure gas introduced through the air inlet passes through the air path 8 and reaches the small hole throttle 10 of the air bearing. After throttling, a stable suspension force is provided for the spindle rotor 3. The rear thrust bearing 9 and the rear air bearing 2 at the tail end jointly provide axial bearing capacity and rigidity, and the rear air bearing 2 and the front air bearing 6 jointly provide radial bearing capacity and rigidity, thereby ensuring that the spindle rotor 3 can achieve frictionless high-speed rotation driven by the drive motor 5.

[0053] like Figure 3 As shown in the rear air bearing structure diagram, the rear end face and inner diameter face of the rear air bearing 2 are both provided with throttles, a plurality of small hole throttles 10 are evenly arranged along the circumferential direction on the rear end face, a plurality of small hole throttles 10 are evenly arranged along the inner diameter circumferential surface on the inner diameter face, and are arranged in multiple rows along the axial direction, the rear air bearing 2 plays both radial and axial bearing roles on the main shaft rotor 3.

[0054] like Figure 1 In the structural cross-sectional view of the precision air spindle shown in the figure, the spindle drive motor 5 is arranged in the middle position of the spindle rotor 3 and is fixed on the rotor by the spindle sleeve 12. This arrangement makes the spindle structure more compact and better supports the rotation of the spindle on the one hand, and can increase the spindle's bearing power and improve the spindle load on the other hand.

[0055] like Figure 4As shown in the schematic diagram of the installation of the shaft end and the grinding wheel cutter, the working end of the spindle rotor 3 of the main shaft is installed with a grinding wheel cutter 13, and the grinding wheel cutter 13 is installed with a grinding wheel blade for chamfering cutting. The grinding wheel cutter 13 and the spindle rotor 3 are connected by a conical surface, and the taper of the conical surface is 1:20.

[0056] like Figure 2 As shown in the structural appearance diagram of the precision air spindle without a casing, a cooling water path 15 is arranged on the cooling water jacket 4. The cooling water flows in from the cooling water inlet on the rear cover 1, cools the air bearing and the drive motor 5 in turn, and then flows out through the cooling water outlet 20 on the rear cover 1.

[0057] like Figure 1 The structural cross-sectional view of the precision air spindle shown in the figure shows that an air path 8 for air intake is arranged on the spindle. High-pressure gas flows in through the air inlet 17 of the rear cover 1, flows through the rear cover 1, and then successively enters the rear thrust bearing 9, the rear air bearing 2 and the front air bearing 6.

[0058] like Figure 5 As shown in the schematic diagram of the tail end interface, after the high-pressure gas is throttled by the air bearing, the gas is discharged through the exhaust groove and the tail outlet 18. The outlet 18 is provided with an exhaust muffler 16 to reduce the noise pollution of the equipment.

[0059] like Figure 1-Figure 5 The precision air electric spindle for wafer chamfering shown in the figure has a spindle rotor 3 made of high-strength, high-rigidity material and a nano-coating applied on the surface to increase the vibration resistance and wear resistance of the spindle.

[0060] The above description is only a preferred embodiment of the present invention, and does not limit the scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the protection scope of the present invention.

Claims

1. A precision air electric spindle for wafer chamfering, characterized in that: include: Spindle rotor, drive motor, front air bearing, rear air bearing, cooling water jacket, rear thrust bearing, front cover, rear cover, outer shell; The spindle rotor is installed in the drive motor, the front end and the rear end of the spindle rotor are respectively sleeved with a front air bearing and a rear air bearing, the cooling water jacket is sleeved on the outside of the front air bearing, the drive motor and the rear air bearing, the rear thrust bearing is located on the outside of the spindle rotor flying disc, the front cover and the rear cover are respectively located on the front side of the front air bearing and the rear side of the rear thrust bearing and are installed on the cooling water jacket, and the outer shell is sleeved on the outside of the cooling water jacket; The outer side of the cooling water jacket is provided with a plurality of grooves, which form cooling water channels for cooling; An air path is provided through the rear cover, the rear thrust bearing, the rear air bearing, and the cooling water jacket; A plurality of first air holes are arranged on the side of the rear thrust bearing facing the main shaft rotor flying disc, the first air holes are connected to the air path, and the first air holes blow air toward the main shaft rotor flying disc to form air suspension between the rear thrust bearing and the main shaft rotor flying disc; The inner diameter surfaces of the front air bearing and the rear air bearing are evenly provided with a plurality of second air holes, which are connected to the air path and blow air toward the spindle rotor to form air suspension between the front air bearing, the rear air bearing and the spindle rotor.

2. The precision air electric spindle for wafer chamfering according to claim 1, characterized in that: The rear cover is provided with an air inlet, an air outlet, a cooling water inlet, a cooling water outlet, and a motor line interface; The air inlet is used to transport gas into the air path, and the gas in the air path is discharged through the first air hole and the second air hole and then discharged through the air outlet; The cooling water inlet is used to input cooling water into the cooling water circuit, and then discharge it from the cooling water outlet; The motor line interface is used to connect the drive motor.

3. The precision air electric spindle for wafer chamfering according to claim 2, characterized in that: A muffler is also provided on the air outlet.

4. The precision air electric spindle for wafer chamfering according to claim 1, characterized in that: A throttle is disposed in each of the first air hole and the second air hole.

5. The precision air electric spindle for wafer chamfering according to claim 1, characterized in that: A shaft sleeve is also arranged between the front air bearing and the main shaft rotor to fix the position of the drive motor on the main shaft rotor.

6. The precision air electric spindle for wafer chamfering according to claim 1, characterized in that: Small hole throttling, porous throttling or slit throttling is arranged between the rear thrust bearing and the main shaft rotor flying disc, between the rear air bearing and the main shaft rotor, and between the front air bearing and the main shaft rotor for blowing air to form air suspension.

7. The precision air electric spindle for wafer chamfering according to claim 1, characterized in that: A grinding wheel cutter disc is also installed at the front end of the spindle rotor via a fastening screw.

8. The precision air electric spindle for wafer chamfering according to claim 7, characterized in that: The front end of the spindle rotor is also provided with a conical surface, and the grinding wheel cutter disc and the spindle rotor are connected and matched via the conical surface.

9. The precision air electric spindle for wafer chamfering according to claim 1, characterized in that: The front air bearing and the rear air bearing are L-shaped.

10. The precision air electric spindle for wafer chamfering according to claim 1, characterized in that: The main shaft rotor is made of high-strength and high-rigidity material, and the surface is coated with a nano-coating to increase the vibration resistance and wear resistance of the main shaft rotor.

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