Multi-station silicon wafer handling mechanism in process chamber

Abstract

The present invention discloses a multi-station silicon wafer handling mechanism in a process chamber, including a main shaft with a wafer transfer tray on the top; a sealing assembly sleeved on the upper part of the main shaft to achieve Z-direction sealing and rotary sealing; a rotating mechanism connected to the lower part of the main shaft to achieve the rotational movement of the main shaft; and a Z-direction lifting mechanism connected to the rotating mechanism to achieve the lifting movement of the main shaft. The sealing assembly includes a bellows assembly for achieving Z-direction sealing and a magnetic fluid vacuum sealing hollow shaft for achieving rotary sealing, the magnetic fluid vacuum sealing hollow shaft is located between the bellows assembly and the main shaft, and a magnetic fluid protective cover is provided at the end of the bellows assembly and the magnetic fluid vacuum sealing hollow shaft. The present application realizes reciprocating rotation and lifting movement suitable for multiple stations by integrating a rotating mechanism and a Z-direction lifting mechanism, which is compact and reasonable as a whole, and adopts a combination of a bellows assembly for Z-direction sealing and a magnetic fluid for rotary vacuum sealing, which has excellent sealing performance and will not cause chamber leakage.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor chip manufacturing equipment, and in particular to a multi-station silicon wafer conveying mechanism in a process chamber. Background Art

[0002] In the semiconductor field, silicon wafers are the most commonly used substrate and are widely used in the manufacture of chips, integrated circuits and electronic devices. During the entire processing of silicon wafers, coating equipment is required to coat the surface of the silicon wafers. At present, most of the silicon wafer handling mechanisms in coating equipment use a purely mechanical method to control the silicon wafer handling position. Its disadvantages are low handling accuracy, slow response, complex structure, overall size and space occupation. In addition, the sealing method of the silicon wafer handling mechanism uses a resin collar and a superimposed sealing ring for sealing. Its disadvantages are that the collar and the sealing ring are easily worn, and the seal is not tight, causing chamber leakage.

[0003] Existing silicon wafer handling mechanisms are designed for single stations in process chambers. They are bulky and difficult to install, and they use a side drive method. The center of gravity and power are not on the same vertical line, and the stability of reciprocating rotation and lifting movement cannot be guaranteed. Summary of the invention

[0004] The purpose of the present invention is to provide a multi-station silicon wafer handling mechanism in a process chamber, which is integrated by a rotating mechanism and a Z-axis lifting mechanism. The overall structure is compact and reasonable, and two sealing methods are adopted, which is suitable for multi-stations to achieve stable reciprocating rotation and lifting.

[0005] To achieve the above-mentioned purpose, the technical solution of the present application is: a multi-station silicon wafer handling mechanism in a process chamber, comprising:

[0006] The spindle, with a wafer transfer tray on top;

[0007] The sealing assembly is sleeved on the upper part of the main shaft to achieve Z-direction sealing and rotary sealing;

[0008] A rotating mechanism is connected to the lower part of the main shaft to realize the rotating movement of the main shaft;

[0009] The Z-axis lifting mechanism is connected with the rotating mechanism to realize the lifting movement of the main shaft.

[0010] As an improvement of the above-mentioned scheme, the sealing assembly includes a bellows assembly for achieving Z-direction sealing and a magnetic fluid vacuum sealing hollow shaft for achieving rotary sealing. The magnetic fluid vacuum sealing hollow shaft is located between the bellows assembly and the main shaft, and a magnetic fluid protective cover is provided at the end of the bellows assembly and the magnetic fluid vacuum sealing hollow shaft.

[0011] As an improvement of the above-mentioned scheme, the bellows assembly is clamped in the upper part of the conveying shell and connected to the top of the Z-axis slider end cover which is sleeved on the main shaft. A circulating water copper pipe for shell cooling is provided in the outer groove of the upper part of the conveying shell, and a circulating water copper pipe for magnetic fluid cooling is provided on the outer periphery of the Z-axis slider end cover.

[0012] As an improvement of the above-mentioned scheme, the rotating mechanism includes a DD motor, a circular grating, and a reading head located at the lower part of the conveying shell, the reading head is installed at the bottom of the Z-axis slider end cover, the top of the inner ring of the DD motor is connected to a base, a circular grating is installed on the base, the inner side of the base is tensioned with the spindle through a keyless sleeve, and a limit piece fixed at the root of the spindle is provided under the base. When the spindle moves upward to the highest point, the limit piece contacts the inner side of the bottom of the base.

[0013] As an improvement of the above-mentioned scheme, the Z-axis lifting mechanism includes a Z-axis servo motor, a Z-axis lead screw, a lead screw nut, and a Z-axis slider body. The Z-axis servo motor located in the electric control box is connected to the lower part of the Z-axis lead screw through a coupling. The upper part of the Z-axis lead screw passes through the bottom of the conveying shell and extends into the DD motor and is located below the main shaft. A lead screw nut is sleeved on the Z-axis lead screw, and the lead screw nut is connected to the Z-axis slider body through a nut spacer. A slider is connected to the side of the Z-axis slider body, and the slider moves up and down along a guide rail. The guide rail is fixed on the side wall of the conveying shell, and a DD motor is fixed on the Z-axis slider body.

[0014] As an improvement of the above scheme, the top of the Z-direction slider body is connected to the Z-direction slider end cover, and the inner side of the Z-direction slider end cover is provided with a double-row radial ball bearing sleeved on the main shaft, the inner side of the bottom of the double-row radial ball bearing is provided with a bearing inner retaining ring, a main shaft locking nut is provided below the bearing inner retaining ring, a locking nut avoidance groove is opened on the base, and the outer side of the bottom of the double-row radial ball bearing is provided with a bearing outer retaining ring.

[0015] As an improvement of the above solution, the coupling is located in the lower part of the integrated seat, the upper part of the integrated seat is provided with a bearing sleeved on the Z-direction screw rod, the integrated seat is fixed to the bottom of the transport shell, and a protective enclosure is provided on the outer periphery of the bottom of the transport shell.

[0016] As an improvement of the above-mentioned scheme, the transport shell is located on the electrical control box, and the electrical control box is provided with a servo motor driver connected to the Z-axis servo motor and a DD motor driver connected to the DD motor. The DD motor driver is fixed to the bottom of the transport shell through a bracket, and the servo motor driver is fixed to the supporting column of the side wall of the electrical control box.

[0017] As an improvement of the above solution, the servo motor driver, DD motor driver and reading head are all connected to the controller in the electric control box, and the servo motor driver and DD motor driver are both located on the base plate, and a buffer base is connected under the base plate.

[0018] As an improvement of the above-mentioned scheme, the bellows assembly includes a bellows body, a bellows and a bellows base. The magnetic fluid vacuum sealing hollow shaft is located in the bellows body. The bellows base is sleeved on the outside of the bellows body. A bellows is provided between the bellows base and the bellows body clamp. The bellows base is fixed on the top of the transport shell.

[0019] Due to the adoption of the above technical scheme, the present invention can achieve the following technical effects: the present application realizes reciprocating rotation and lifting motion suitable for multiple stations by integrating the rotating mechanism and the Z-direction lifting mechanism, which is compact and reasonable as a whole, and adopts a combination of a bellows assembly for Z-direction sealing and a magnetic fluid for rotary vacuum sealing, which has excellent sealing performance and will not cause chamber leakage. The double-row radial ball bearing can withstand large radial and axial loads, increases the load-bearing capacity of the main shaft, and improves stability; the vertical drive mode is adopted, the center of gravity and the power are on the same vertical line, and the rotation angle is accurately known through the cooperation of the reading head and the circular grating, so as to realize accurate and stable transposition of the wafer, which is convenient for the collaborative work of multiple stations. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is the appearance diagram of the multi-station silicon wafer handling mechanism in the process chamber;

[0021] Figure 2 for Figure 1 AA section view;

[0022] Figure 3 is a schematic diagram of a bellows assembly;

[0023] Explanation of the numbers in the figure: 1. Bellows assembly; 2. Spindle; 3. Magnetic fluid vacuum sealed hollow shaft; 4. Magnetic fluid protective cover; 5. Handling shell; 6. Circulating water copper pipe for shell cooling; 7. Circulating water copper pipe for magnetic fluid cooling; 8. Z-axis slider end cover; 9. Double-row radial ball bearing; 10. Bearing inner retaining ring; 11. Bearing outer retaining ring; 12. Spindle locking nut; 13. Reading head; 14. Circular grating; 15. Base; 16. Keyless bushing; 17. Guide rail; 18. Slider; 19. Z-axis slider body; 20. DD motor body; 21. Z-axis lead screw; 22. Lead screw nut; 23. Nut spacer; 24. Protective enclosure; 25. Integrated seat; 26. Coupling; 27. Z-axis servo motor; 28. Servo motor driver; 29. ​​DD motor driver; 30. Bracket; 31. Support column; 32. Foot plate; 33. Buffer foot; 34. Electric control box; 111. Bellows body; 112. Bellows; 113. Bellows base. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the present invention will be further described below in conjunction with the embodiments and drawings.

[0025] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0026] In the description of the present invention, the terms "comprises," "comprising" or any other variations thereof are intended to cover a non-exclusive inclusion, and may include other elements not explicitly listed in addition to those listed elements.

[0027] Example 1

[0028] like Figures 1-2 As shown, this embodiment provides a multi-station silicon wafer handling mechanism in a process chamber, including a spindle, a sealing assembly, a rotating mechanism and a Z-direction lifting mechanism;

[0029] In this embodiment, a sealing assembly is defined, which includes a bellows assembly for achieving Z-direction sealing and a magnetic fluid vacuum sealing hollow shaft for achieving rotational sealing, the magnetic fluid vacuum sealing hollow shaft is located between the bellows assembly and the main shaft, and a magnetic fluid protective cover is provided at the ends of the bellows assembly and the magnetic fluid vacuum sealing hollow shaft. The bellows assembly is clamped in the upper part of the transport shell, and is connected to the top of the Z-direction slider end cover sleeved on the main shaft, a circulating water copper pipe for shell cooling is provided in the outer groove of the upper part of the transport shell, and a circulating water copper pipe for magnetic fluid cooling is provided on the outer periphery of the Z-direction slider end cover.

[0030] Specifically, the bellows assembly includes a bellows body, a bellows and a bellows base. The magnetic fluid vacuum sealed hollow shaft is located in the bellows body. The bellows base is sleeved on the outside of the bellows body. A bellows is provided between the bellows base and the bellows body clamp. The bellows base is fixed on the top of the transport shell.

[0031] It should be noted that the structural design of the bellows Z-axis seal and the combined application of the rotary vacuum seal achieved by the magnetic fluid are used in this handling mechanism and can also be used in this industry and similar equipment.

[0032] In this embodiment, a rotating mechanism is defined, which includes a DD motor, a circular grating, and a reading head located at the bottom of the transport housing. The reading head is installed at the bottom of the Z-axis slider end cover. The top of the inner ring of the DD motor is connected to a base, and a circular grating is installed on the base. The inner side of the base is tensioned with the spindle through a keyless sleeve. A limiter fixed to the root of the spindle is provided below the base. When the spindle moves upward to the highest point, the limiter contacts the inner side of the base bottom card. The accurate and stable silicon wafer transposition is achieved through the DD motor and high-precision grating feedback.

[0033] In this embodiment, a Z-direction lifting mechanism is defined, which includes a Z-direction servo motor, a Z-direction lead screw, a lead screw nut, and a Z-direction slider body. The Z-direction servo motor located in the electric control box is connected to the lower part of the Z-direction lead screw through a coupling. The upper part of the Z-direction lead screw passes through the bottom of the transport shell and extends into the DD motor and is located below the main shaft. A lead screw nut is sleeved on the Z-direction lead screw, and the lead screw nut is connected to the Z-direction slider body through a nut pad. A slider is connected to the side of the Z-direction slider body. The slider moves up and down along a guide rail, and the guide rail is fixed on the side wall of the transport shell. The DD motor is fixed on the Z-direction slider body. The top of the Z-direction slider body is connected to the Z-direction slider end cover. The inner side of the Z-direction slider end cover is provided with a double-row radial ball bearing sleeved on the main shaft. The inner side of the bottom of the double-row radial ball bearing is provided with a bearing inner retaining ring. A spindle locking nut is provided below the bearing inner retaining ring. A locking nut avoidance groove is provided on the base. The outer side of the bottom of the double-row radial ball bearing is provided with a bearing outer retaining ring.

[0034] Specifically, the coupling is located in the lower part of the integrated seat, the upper part of the integrated seat is provided with a bearing sleeved on the Z-axis screw rod, the integrated seat is fixed to the bottom of the transport shell, and a protective enclosure is provided on the outer periphery of the bottom of the transport shell. The transport shell is located on the electric control box, and the electric control box is provided with a servo motor driver connected to the Z-axis servo motor and a DD motor driver connected to the DD motor. The DD motor driver is fixed to the bottom of the transport shell through a bracket, and the servo motor driver is fixed to the supporting column of the side wall of the electric control box. The servo motor driver, DD motor driver, and reading head are all connected to the controller in the electric control box, and the servo motor driver and DD motor driver are all located on the foot plate, and a buffer foot is connected under the foot plate.

[0035] It should be noted that the advantage of setting up double-row radial ball bearings is that it can reduce the friction between rotating parts, thereby reducing heat generation, improving the rotation accuracy of the spindle, extending the service life of the spindle, saving maintenance and replacement costs, and reducing noise; the most important thing is that it can withstand larger radial and axial loads, increase the load-bearing capacity of the spindle, and improve stability.

[0036] In this embodiment, a method for rotating and lifting a multi-station silicon wafer handling mechanism in a process chamber is provided, which specifically includes:

[0037] Rotational motion: The controller controls the rotation of the inner ring of the DD motor. The DD motor drives the spindle to rotate through the base and keyless sleeve. The spindle drives the wafer transfer tray to achieve the purpose of transporting the wafer. The reading head captures the high-precision circular grating position feedback signal and transmits it to the controller. The controller controls the rotation accuracy of the spindle according to work needs.

[0038] Lifting motion: The controller controls the Z-axis servo motor to work, and converts the rotational motion into linear motion through the cooperation of the Z-axis lead screw and the lead screw nut, thereby driving the Z-axis slider body to move linearly along the guide rail. The Z-axis slider body drives the spindle to move up and down through the Z-axis slider end cover.

[0039] The above-mentioned compact and reasonable overall structural design, the realization principle of the rotating structure and the Z-axis lifting structure, the layout of the selected components and parts in the structure, and the high-precision positioning realization method can be applied to this industry and similar equipment. This industry refers to the semiconductor industry and the manufacture of semiconductor chips. Similar equipment is one of the core equipment required for chip manufacturing: thin film deposition equipment, plasma enhanced CVD (PECVD) The present invention is a transport mechanism for multiple silicon wafer stations in a PECVD process chamber: multiple silicon wafers are deposited simultaneously, and the positions are changed according to the process to ensure the uniformity of the deposited film. The necessary silicon wafer transport mechanism.

[0040] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A multi-station silicon wafer handling mechanism in a process chamber, characterized in that: include: The spindle, with a wafer transfer tray on top; The sealing assembly is sleeved on the upper part of the main shaft to achieve Z-direction sealing and rotary sealing; A rotating mechanism is connected to the lower part of the main shaft to realize the rotating movement of the main shaft; The Z-axis lifting mechanism is connected with the rotating mechanism to realize the lifting and lowering movement of the spindle; The sealing assembly includes a bellows assembly for achieving Z-direction sealing and a magnetic fluid vacuum sealing hollow shaft for achieving rotational sealing, wherein the magnetic fluid vacuum sealing hollow shaft is located between the bellows assembly and the main shaft, and a magnetic fluid protective cover is provided at the ends of the bellows assembly and the magnetic fluid vacuum sealing hollow shaft; The bellows assembly is clamped in the upper part of the transport shell and connected to the top of the Z-direction slider end cover sleeved on the main shaft. A circulating water copper pipe for shell cooling is provided in the outer groove of the upper part of the transport shell, and a circulating water copper pipe for magnetic fluid cooling is provided on the outer periphery of the Z-direction slider end cover; The rotating mechanism includes a DD motor, a circular grating, and a reading head located at the lower part of the conveying shell. The reading head is installed at the bottom of the Z-axis slider end cover. The top of the inner ring of the DD motor is connected to a base, and a circular grating is installed on the base. The inner side of the base is tensioned with the spindle through a keyless sleeve. A limiter fixed at the root of the spindle is provided under the base. When the spindle moves upward to the highest point, the limiter contacts the inner side of the bottom of the base.

2. The multi-station silicon wafer handling mechanism in the process chamber according to claim 1, characterized in that: The Z-axis lifting mechanism includes a Z-axis servo motor, a Z-axis lead screw, a lead screw nut, and a Z-axis slider body. The Z-axis servo motor located in the electric control box is connected to the lower part of the Z-axis lead screw through a coupling. The upper part of the Z-axis lead screw passes through the bottom of the transport shell and extends into the DD motor and is located below the main shaft. A lead screw nut is sleeved on the Z-axis lead screw, and the lead screw nut is connected to the Z-axis slider body through a nut pad. A slider is connected to the side of the Z-axis slider body, and the slider moves up and down along a guide rail. The guide rail is fixed on the side wall of the transport shell, and a DD motor is fixed on the Z-axis slider body.

3. The multi-station silicon wafer handling mechanism in the process chamber according to claim 2, characterized in that: The top of the Z-direction slider body is connected to the Z-direction slider end cover, and a double-row radial ball bearing sleeved on the main shaft is arranged on the inner side of the Z-direction slider end cover, a bearing inner retaining ring is arranged on the inner side of the bottom of the double-row radial ball bearing, a main shaft locking nut is arranged below the bearing inner retaining ring, a locking nut avoidance groove is opened on the base, and a bearing outer retaining ring is arranged on the outer side of the bottom of the double-row radial ball bearing.

4. The multi-station silicon wafer handling mechanism in a process chamber according to claim 2, characterized in that: The coupling is located in the lower part of the integrated seat, the upper part of the integrated seat is provided with a bearing sleeved on the Z-direction screw rod, the integrated seat is fixed to the bottom of the transport shell, and a protective enclosure is provided on the outer periphery of the bottom of the transport shell.

5. The multi-station silicon wafer handling mechanism in a process chamber according to claim 2, characterized in that: The transport shell is located on the electric control box, which is equipped with a servo motor driver connected to the Z-axis servo motor and a DD motor driver connected to the DD motor. The DD motor driver is fixed to the bottom of the transport shell through a bracket, and the servo motor driver is fixed to the supporting column of the side wall of the electric control box.

6. The multi-station silicon wafer handling mechanism in a process chamber according to claim 5, characterized in that: The servo motor driver, DD motor driver and reading head are all connected to the controller in the electric control box. The servo motor driver and DD motor driver are both located on the foot plate, and a buffer foot is connected under the foot plate.

7. The multi-station silicon wafer handling mechanism in a process chamber according to claim 1, characterized in that: The bellows assembly includes a bellows body, a bellows and a bellows base. The magnetic fluid vacuum sealing hollow shaft is located in the bellows body. The bellows base is sleeved on the outside of the bellows body. A bellows is provided between the bellows base and the bellows body clamp. The bellows base is fixed on the top of the transport shell.

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