Horizontal wafer spin etching mechanism

Abstract

The utility model discloses a horizontal wafer rotary etching mechanism, including motor, transmission pair, mounting panel, pivot, rotary drum, transmission pair, pivot correspond to be equipped on mounting panel, and the motor passes through transmission pair and drives the rotation of pivot, and the rotary drum is located on the pivot, and the rotary drum is equipped with clamp and quick detach block, is equipped with a plurality of placement groove for placing wafer on the clamp, and the quick detach block is used for pressing the wafer in the placement groove, and the wafer in the placement groove is with the rotary tangent direction of rotary drum angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of inclination angle of

Description

Technical Field

[0001] This utility model relates to the field of crystal oscillator manufacturing technology, and in particular to a horizontal wafer rotation etching mechanism. Background Technology

[0002] In the wet chemical etching process for 3215-type wafers (such as quartz crystal resonators), to obtain precise frequency and surface finish, it is essential to strictly control the flow field distribution and mechanical impact force of the etching solution. Existing technologies suffer from the following bottlenecks: The contradiction between angle sensitivity and yield: Traditional fixtures mostly use parallel (0°) or vertical (90°) placement. When placed in parallel, a laminar boundary layer is easily formed on the wafer surface, the etchant is replaced slowly, resulting in incomplete etching; when placed vertically, the liquid flow impact force acts vertically on the thin and brittle wafer, which can easily cause wafer cracking or edge chipping.

[0003] Low wafer retrieval efficiency: Each fixture holds more than 20 wafers. Traditional structures require unscrewing screws or removing pins one by one to retrieve the wafers, which is not only time-consuming but also prone to damaging the wafer surface during operation.

[0004] Equipment corrosion and maintenance are difficult: corrosive solutions (hydrofluoric acid, strong alkalis, etc.) are highly volatile. If the motor is directly immersed in the liquid, the seals are prone to aging and leakage; if an external belt pulley drive is used, it occupies a large area and the speed is unstable. Existing equipment struggles to strike a balance between batch immersion and motor safety.

[0005] Therefore, developing a corrosion mechanism that integrates angled flow field optimization, two-stage quick-release structure and dual-state anti-corrosion drive is key to improving the production capacity and yield of 3215 wafers. Utility Model Content

[0006] The technical problem to be solved by this utility model embodiment is to provide a horizontal wafer rotation etching mechanism to improve the production capacity and yield of 3215 wafers.

[0007] To address the aforementioned technical problems, this utility model provides a horizontal wafer rotation etching mechanism, comprising a motor, a transmission pair, a mounting plate, a rotating shaft, and a rotating drum. The transmission pair and the rotating shaft are correspondingly mounted on the mounting plate. The motor drives the rotating shaft to rotate via the transmission pair. The rotating drum is mounted on the rotating shaft and is equipped with a clamp and a quick-release block. The clamp is provided with several placement slots for placing wafers, and the quick-release block is used to press the wafers in the placement slots. The wafers in the placement slots form a preset angle with the tangential direction of the rotating drum's rotation.

[0008] Furthermore, the rotating drum includes two clamping side plates, with the clamps disposed between the two clamping side plates.

[0009] Furthermore, it also includes a locking nut, the rotating shaft passes through the center of the two clamp side plates of the rotating cylinder, and the clamps are multiple and evenly spaced around the rotating shaft; the locking nut is mounted on the rotating shaft to fix the rotating cylinder on the rotating shaft.

[0010] Furthermore, the rotating shaft is provided with a limiting part corresponding to the rotating drum, and the rotating drum is clamped and fixed by the locking nut and the limiting part.

[0011] Furthermore, the placement slots on the fixture are arranged side by side along the axial direction.

[0012] Furthermore, one end of the quick-release block is mounted on a side plate of a clamp via a rotating shaft, the other end of the quick-release block is provided with a slot, and a corresponding locking pin is provided on the other side plate of the clamp.

[0013] Furthermore, the fixture consists of a wafer support block and two wafer side plates corresponding to each other on both sides of the wafer support block.

[0014] Furthermore, the center of the chip's side plate is hollowed out.

[0015] Furthermore, the transmission pair is a multi-stage gear drive structure.

[0016] Furthermore, the preset angle is 15°±0.5°.

[0017] The beneficial effects of this utility model are as follows: 1) The yield rate of this utility model is greatly improved: the 15° oblique angle is the balance point of fluid mechanics and material mechanics, which completely eliminates the defects of parallel non-corrosion and vertical easy fragmentation. The corrosion depth uniformity is improved to more than 98% after testing.

[0018] 2) The efficiency of this utility model is doubled: This utility model reduces the changeover time from 30 minutes to 1 minute, and the quick-release block reduces the time to pick up 20 wafers at a time from 5 minutes to 10 seconds, while avoiding scratches on individual wafers.

[0019] 3) Full life cycle protection of equipment: The motor of this utility model is always in a dry area, which completely solves the problem of corrosion of expensive servo motors by corrosive liquid vapor, and reduces the equipment failure rate by 90%.

[0020] 4) Process flexibility: The same set of equipment can be adapted to the production needs of large-volume single products by changing its posture. Attached Figure Description

[0021] Figure 1 This is a structural diagram of the horizontal wafer rotation etching mechanism according to an embodiment of the present invention.

[0022] Figure 2 This is an exploded view of the horizontal wafer rotary etching mechanism according to an embodiment of the present invention.

[0023] Figure 3This is a three-dimensional structural diagram of the rotating drum according to an embodiment of the present invention.

[0024] Figure 4 This is a three-dimensional structural diagram of the clamp according to an embodiment of the present utility model.

[0025] Figure 5 This is a schematic diagram of the angle structure between the wafer and the rotation tangent direction in an embodiment of this utility model.

[0026] Explanation of icon numbers 1. Wafer, 2. Rotation tangent direction, 3. Preset angle, 4. Etching tank, 5. Etching liquid area, 10. Rotating drum, 11. Fixture side plate, 12. Quick release block, 13. Rotating shaft, 14. Locking pin, 15. Locking groove, 20. Motor, 21. Mounting plate, 22. Rotating shaft, 23. Locking nut, 24. Limiting part, 25. Transmission pair, 30. Fixture, 31. Wafer support block, 32. Wafer side plate. Detailed Implementation

[0027] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other. The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] In this embodiment of the invention, directional indicators (such as up, down, left, right, front, back, etc.) are only used to explain the relative positional relationship and movement of the components in a specific posture (as shown in the attached figure). If the specific posture changes, the directional indicators will also change accordingly.

[0029] Furthermore, in this utility model, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0030] Please refer to Figures 1-5 The horizontal wafer rotation etching mechanism of this utility model includes a motor, a transmission pair, a mounting plate, a rotating shaft, a rotating cylinder, and a locking nut.

[0031] The transmission pair and rotating shaft are correspondingly mounted on the mounting plate, and the motor drives the rotating shaft to rotate through the transmission pair. The rotating drum is detachably mounted on the rotating shaft. The rotating shaft is a hollow stepped shaft, with the lower end used to connect to the rotating drum and the upper end connected to the transmission pair. In this invention, the center of the rotating drum adopts an insertion-type + knob locking structure to achieve second-level separation between the rotating drum and the rotating shaft. The transmission pair is a multi-stage gear drive structure. This invention indirectly drives the rotating drum immersed in the corrosive liquid (part of the transmission pair is located within the corrosive liquid area) through the multi-stage gear reversing transmission and the transmission pair. The rotating drum can lie horizontally and be fully submerged, while the motor remains suspended above the liquid surface, completely isolating it from corrosion. During operation, the motor is fixed above and outside the corrosion tank, and the output shaft is connected to the driving gear of the multi-stage gear drive structure. The driven gear is meshed with the intermediate gear (idler gear) fixed on the mounting plate to achieve steering transmission. In specific implementation, a bushing is provided in the middle of the rotating drum. After the rotating drum is fitted onto the rotating shaft through the bushing, it is axially fixed by the radial locking nut on the side. The axial quick-locking structure of the rotating shaft and locking nut of this utility model can separate the rotating drum and the rotating shaft without tools.

[0032] The rotating drum includes two clamping side plates, with the clamps positioned between them. A rotating shaft passes through the center of the two clamping side plates. Multiple clamps are evenly spaced around the rotating shaft. The clamping side plates are preferably circular, arranged vertically, with six uprights forming a cage-like structure in the center. Preferably, six sets of clamps are evenly distributed and fixed between the two plates. A locking nut is mounted on the rotating shaft, securing the rotating drum to it. The rotating shaft has a corresponding limiting part for the rotating drum, which is clamped and fixed by the locking nut and the limiting part. Placement slots on the clamps are arranged side-by-side along the axial direction.

[0033] The rotary drum is equipped with clamps and quick-release blocks. Each clamp has a rotating quick-release block on top. The operator only needs to rotate the quick-release block by one angle (such as 90°) to release the clamping force on the wafers, and the entire stack (more than 20 wafers) can be removed at once without the need for individual wafer separation. The clamp has several placement slots for placing wafers, and the quick-release blocks are used to clamp the wafers in the placement slots.

[0034] One end of the quick-release block is mounted on one side plate of the fixture via a rotating shaft, and the other end of the quick-release block has a slot. A corresponding locking pin is provided on the other side plate of the fixture. In practice, the quick-release block can also be mounted on the fixture base via a hinge or sliding groove, allowing the wafer to be quickly removed by rotating the quick-release block. The fixture consists of a wafer support block and two wafer side plates corresponding to both sides of the wafer support block. The wafer side plates have a hollow center to facilitate full contact between the wafer and the etching solution within the fixture. Placement slots are provided on both sides of the wafer side plates.

[0035] The wafer placed in the slot forms a preset angle with the rotation direction of the rotating drum. The preset angle is 15° ± 0.5°. Preferably, the wafer maintains a 15° angle with the tangential direction of rotation. This invention utilizes the Coriolis force effect generated by oblique rotation to create micro-turbulence in the etching solution on the wafer surface, which not only breaks down the stagnant boundary layer (solving the problem of incomplete etching) but also decomposes the normal impact force into tangential components (solving the problem of wafer cracking).

[0036] The working process of this utility model is as follows: Assembly: Secure the six fixtures, each filled with wafers, to the circumference of the rotating drum. Align the center hole of the rotating drum with the shaft and insert it, then tighten the lock nut to lock it in place.

[0037] Layout: The entire mechanism is hoisted into the corrosion tank, and the corrosion liquid is injected. The liquid level covers 80% of the height of the rotating drum, but ensures that the liquid level is below the connection flange between the rotating shaft and the motor.

[0038] Corrosion: Start the motor and set the speed to 40 rpm. Due to the 15° tilt angle, the wafer forms an oblique cutting fluid during rotation, and the surface is constantly renewed.

[0039] Unloading: After corrosion is complete, there is no need to disassemble the entire rotating drum. The operator stands at the edge of the tank, reaches out and rotates the quick-release block above a set of clamps 90 degrees. The quick-release block will release, and the entire stack of wafers can be lifted directly with tweezers. If the rotating drum needs to be cleaned, loosen the bottom locking nut, lift the shaft, and the entire rotating drum will be removed from the liquid surface for cleaning.

[0040] Verification tests of the flow field and stress at a 15° oblique angle for this invention: Method: A simulated rotating cylinder was fabricated using transparent PMMA material, and a tracer fluid with the same viscosity and density as the actual etching solution was injected. Micro-strain gauges were then attached to the wafer surface.

[0041] Process: Flow velocity vector diagrams and wafer stress waveforms were tested at four angles: 0°, 15°, 30°, and 90°.

[0042] Judgment criteria: Under 15° operating conditions, the wafer surface should show obvious "adhesion vortex shedding" phenomenon (proving high mass transfer efficiency), and the peak value of normal impact stress should be less than 20% of the wafer's flexural strength (such as 50MPa for quartz), while the tangential component force should be greater than 0.5N / cm² to remove air bubbles.

[0043] Durability and chip removal efficiency of the quick-release block of this utility model: Method: Select a set of fixtures and load 20 dummy chips (simulating weight).

[0044] Procedure: Perform a continuous cycle of "locking-rotating to unlock-remove piece-insertion-locking" 1000 times. Record the time for each operation and observe the wear of the quick-release block's locking tongue using a microscope.

[0045] Judgment criteria: The time for a single piece removal should be <5 seconds (compared to >60 seconds for traditional screw structures); after 1000 cycles, the increase in the clearance between the quick-release block and the locking tongue should be <0.1mm, with no jamming.

[0046] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A horizontal wafer rotary etching mechanism, characterized in that, It includes a motor, a transmission pair, a mounting plate, a rotating shaft, and a rotating drum. The transmission pair and the rotating shaft are respectively mounted on the mounting plate. The motor drives the rotating shaft to rotate through the transmission pair. The rotating drum is mounted on the rotating shaft and is equipped with a clamp and a quick-release block. The clamp is equipped with several placement slots for placing wafers. The quick-release block is used to press the wafers in the placement slots. The wafers in the placement slots form a preset angle with the tangential direction of the rotating drum.

2. The horizontal wafer rotary etching mechanism as described in claim 1, characterized in that, The rotating drum includes two clamping side plates, and the clamps are disposed between the two clamping side plates.

3. The horizontal wafer rotation etching mechanism as described in claim 2, characterized in that, It also includes a locking nut, the rotating shaft passes through the center of the two clamp side plates of the rotating cylinder, and the clamps are multiple and evenly spaced around the rotating shaft; the locking nut is installed on the rotating shaft to fix the rotating cylinder on the rotating shaft.

4. The horizontal wafer rotation etching mechanism as described in claim 3, characterized in that, The rotating shaft is equipped with a limiting part corresponding to the rotating drum, and the rotating drum is clamped and fixed by the locking nut and the limiting part.

5. The horizontal wafer rotation etching mechanism as described in claim 2, characterized in that, The placement slots on the fixture are arranged side by side along the axial direction.

6. The horizontal wafer rotary etching mechanism as described in claim 2, characterized in that, One end of the quick-release block is mounted on one side of the clamping plate via a rotating shaft, and the other end of the quick-release block is provided with a slot, and a corresponding locking pin is provided on the other side of the clamping plate.

7. The horizontal wafer rotation etching mechanism as described in claim 1, characterized in that, The fixture consists of a wafer support block and two wafer side plates located on both sides of the wafer support block.

8. The horizontal wafer rotary etching mechanism as described in claim 7, characterized in that, The middle of the chip's side plate is hollowed out.

9. The horizontal wafer rotary etching mechanism as described in claim 1, characterized in that, The transmission pair is a multi-stage gear drive structure.

10. The horizontal wafer rotary etching mechanism as described in claim 1, characterized in that, The preset angle is 15°±0.5°.

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