Annealing support for single crystal silicon wafers

Abstract

This utility model relates to the field of semiconductor manufacturing equipment, and more particularly to an annealing support for monocrystalline silicon wafers. The support includes a water tank and water pipes. Several support rods are connected to the top of the water tank, and a buffer layer is connected to the top of all the support rods. A gear ring is rotatably connected to the top of the buffer layer. A mounting bracket is connected to the side of the buffer layer, and a motor is mounted at the bottom of the mounting bracket. A gear is connected to the motor's output shaft, meshing with the gear ring. Cooling blades are connected to the top of the gear ring, and a flow distribution layer is connected to the top of the cooling blades. A rotating connecting seat is rotatably connected to the top of the flow distribution layer. The top of the rotating connecting seat is connected to the bottom of the water tank via a water pipe. A water pump is installed at one end of the water pipe inside the water tank. The internal flow channels of the cooling blades enhance the turbulence of the coolant and achieve uniform distribution. Combined with the plate heat exchange structure of the cooler, the heat exchange efficiency is improved, allowing heat from the silicon wafer surface to be rapidly transferred to the coolant through forced convection, reducing the temperature difference within the wafer and improving the temperature uniformity of the annealing process.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor manufacturing equipment, and more particularly to an annealing support for monocrystalline silicon wafers. Background Technology

[0002] Monocrystalline silicon wafers, as the core substrate for semiconductor devices and the photovoltaic industry, directly affect the electrical characteristics and reliability of end products. In the manufacturing process of monocrystalline silicon wafers, annealing is a key heat treatment step, primarily achieving the following functions through precise temperature field control: repairing lattice defects caused by ion implantation or grain boundary migration, activating dopant elements to regulate carrier concentration, eliminating residual processing stress, and optimizing thin film density. Annealing temperatures are typically dynamically adjusted within the range of 500°C to 1100°C. For example, shallow junction formation requires activation at temperatures above 950°C, while stress relief uses annealing at 500°C, with time precision controlled to the second level to avoid excessive impurity diffusion.

[0003] Among existing annealing equipment, the utility model patent with announcement number CN217438343U discloses a vertical clamping annealing bracket. Its technical solution uses an upper and lower chuck structure to axially fix the monocrystalline silicon wafer and relies on a rotary motor to drive the wafer carrier disk to rotate at high speed, utilizing centrifugal effect to accelerate heat convection. Although this design can improve the initial cooling rate through the forced airflow generated by rotation, the vertical clamping structure causes localized thermal resistance in the contact area between the silicon wafer edge and the chuck. During rotation, the cooling rate in this area lags behind the central area by 15-20%, resulting in excessive wafer warpage. The airflow turbulence caused by high-speed rotation leads to temperature uniformity deviations; actual measurement data shows a large temperature difference within the wafer, and the heat exchange efficiency of rotational cooling is significantly affected by ambient humidity.

[0004] In summary, while existing rotary annealing supports can achieve basic cooling functions, they suffer from core defects such as uneven thermal stress distribution and poor process stability, making it difficult to meet the stringent requirements of advanced processes for annealing uniformity and yield. Utility Model Content

[0005] To overcome the drawbacks of uneven thermal stress distribution and poor process stability, this invention provides an annealing support for monocrystalline silicon wafers, aiming to solve the aforementioned shortcomings.

[0006] An annealing support for monocrystalline silicon wafers includes a water tank and water pipes. Several support rods are connected to the top of the water tank, and a buffer layer is connected to the top of all the support rods. A gear ring is rotatably connected to the top of the buffer layer. A mounting frame is connected to the side of the buffer layer, and a motor is mounted at the bottom of the mounting frame. A gear is connected to the output shaft of the motor, and the gear meshes with the gear ring. Cooling blades are connected to the top of the gear ring, and a flow divider is connected to the top of the cooling blades. A rotating connecting seat is rotatably connected to the top of the flow divider. The top of the rotating connecting seat is connected to the bottom of the water tank via the water pipes. A water pump is installed at one end of the water pipes inside the water tank. A cooler is installed between the water tank and the buffer layer. The top of the cooler is connected to the buffer layer, and the bottom of the cooler is connected to the water tank. The rotating connecting seat is connected to the flow divider. The cooling blades have multiple placement intervals, and clamping components for holding the monocrystalline silicon wafers are provided within the cooling blades.

[0007] Optionally, the clamping assembly includes a connecting plate, a guide rod, and a return spring. A pressure plate is threadedly connected to the top of the flow divider. Several connecting plates are vertically slidably connected within the flow divider. The bottom of each connecting plate passes through the flow divider and is connected to a top block. Several top blocks are connected to the top surface of the gear ring. The top blocks are located at the top and bottom ends of the cooling blades. Guide rods are slidably connected to both sides of each top block. One end of each guide rod passes through the top block and is connected to a contact plate. A return spring is sleeved on the guide rod. One end of the return spring is connected to the top block, and the other end is connected to the contact plate.

[0008] Optionally, a protective pad is laid inside the top block.

[0009] Optionally, the top of the pressure plate is connected to several protrusions.

[0010] Optionally, a liquid level sensor is installed inside the water tank.

[0011] Optionally, the bottom of the water tank is connected to several stabilizing feet.

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows: 1. By using the flow channels inside the cooling blades, the turbulence effect of the coolant is enhanced and uniform distribution is achieved. Combined with the plate heat exchange structure of the cooler, the heat exchange efficiency is improved, and the heat on the surface of the silicon wafer is quickly transferred to the coolant through forced convection, reducing the temperature difference within the wafer and improving the temperature uniformity of the annealing process.

[0013] 2. By cooperating with the reset spring of the contact plate, the silicon wafer can be quickly positioned and held in two-way elastic clamping, reducing local stress concentration during the clamping process, protecting the silicon wafer surface from scratches, and ultimately reducing the risk of uneven thermal stress distribution. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0015] Figure 2 This is a cross-sectional view of the installation structure of the flow distribution layer and the rotary connecting seat of this utility model.

[0016] Figure 3 This is a schematic diagram of the installation structure of the pressure plate and connecting plate of this utility model.

[0017] Figure 4 This is a schematic diagram of the installation structure of the reset spring and guide rod of this utility model.

[0018] The markings in the attached diagram are as follows: 1: Water tank, 2: Support rod, 3: Buffer layer, 4: Gear ring, 5: Mounting bracket, 501: Gear, 6: Motor, 7: Cooling blade, 8: Flow divider, 9: Rotary connecting seat, 10: Water pipe, 11: Water pump, 12: Cooler, 13: Pressure plate, 14: Connecting plate, 15: Top block, 16: Contact plate, 17: Guide rod, 18: Return spring, 19: Protective pad, 20: Protrusion, 21: Liquid level sensor, 22: Stabilizing foot. Detailed Implementation

[0019] The embodiments of this utility model will be described below with reference to the accompanying drawings.

[0020] Example: Annealing support for monocrystalline silicon wafers, such as Figures 1-4 As shown, the system includes a water tank 1, support rods 2, a buffer layer 3, a gear ring 4, a mounting bracket 5, a gear 501, a motor 6, cooling blades 7, a flow divider 8, a rotary connector 9, water pipes 10, a water pump 11, a cooler 12, and a clamping assembly. Several support rods 2 are connected to the top of the water tank 1. A buffer layer 3 is connected to the top of all support rods 2. A gear ring 4 is rotatably connected to the top of the buffer layer 3. A mounting bracket 5 is connected to the side of the buffer layer 3. A motor 6 is mounted at the bottom of the mounting bracket 5. The output shaft of the motor 6 is connected to a gear 501, which meshes with the gear ring 4. Cooling blades 7 are connected to the top surface of the gear ring 4. The top of the 7 is connected to the diversion layer 8, and the top of the diversion layer 8 is rotatably connected to the rotating connecting seat 9. The rotating connecting seat 9 has a built-in dynamic sealing ring to prevent liquid leakage. The top of the rotating connecting seat 9 is connected to the bottom of the water tank 1 through the water pipe 10. The end of the water pipe 10 located inside the water tank 1 is equipped with a water pump 11. A cooler 12 is installed between the water tank 1 and the buffer layer 3. The top of the cooler 12 is connected to the buffer layer 3, and the bottom of the cooler 12 is connected to the water tank 1. The rotating connecting seat 9 is connected to the diversion layer 8. The cooling blades 7 are provided with multiple placement intervals. Clamping components for clamping single crystal silicon wafers are provided in the placement intervals of the cooling blades 7.

[0021] like Figure 3 and Figure 4As shown, the clamping assembly includes a pressure plate 13, a connecting plate 14, a top block 15, a contact plate 16, a guide rod 17, and a return spring 18. The pressure plate 13 is threadedly connected to the top of the diversion layer 8. Several connecting plates 14 are vertically slidably connected within the diversion layer 8. The bottom of the connecting plate 14 passes through the diversion layer 8 and is connected to the top block 15. The contact surface of the top block 15 is provided with a 30° inclined guide surface to facilitate rapid positioning of the silicon wafer. Several top blocks 15 are connected to the top surface of the gear ring 4. The top blocks 15 are located at the top and bottom ends of the cooling blades 7, respectively. Guide rods 17 are slidably connected to both sides of the top block 15. One end of the guide rod 17 passes through the top block 15 and is connected to the contact plate 16. The surface of the contact plate 16 is coated with Teflon coating, which has a low coefficient of friction. The guide rod 17 is fitted with a return spring 18. One end of the return spring 18 is connected to the top block 15, and the other end is connected to the contact plate 16.

[0022] like Figure 4 As shown, it also includes a protective pad 19. The top block 15 is covered with a protective pad 19, which is made of silicone material that can withstand high temperatures of 300°C and has both insulation and cushioning functions.

[0023] like Figure 3 As shown, it also includes protrusions 20. Several protrusions 20 are connected to the top of the pressure plate 13, and the protrusions 20 are distributed in a ring array along the center point of the pressure plate 13.

[0024] like Figure 2 As shown, it also includes a liquid level sensor 21. The liquid level sensor 21 is installed in the water tank 1. The sensor is set to a low water level threshold of 20% of the water level in the water tank 1.

[0025] like Figure 1 As shown, it also includes stabilizing feet 22. Several stabilizing feet 22 are connected to the bottom of the water tank 1, and rubber shock-absorbing pads are installed at the bottom of the stabilizing feet 22.

[0026] Based on the thickness of the monocrystalline silicon wafer to be annealed, the operator rotates the pressure plate 13 via bump 20, utilizing the upright structure of bump 20 to enhance the stability of force application during operation. When the pressure plate 13 rotates along the thread of the distribution layer 8, it generates axial displacement, pushing the connecting plate 14 and causing the top block 15 to move downwards. The distance between the two top blocks 15 is adjusted to match the height of the silicon wafer. The silicon wafer is placed horizontally in the V-groove of the bottom top block 15. The inclined surface of the contact plate 16 guides the silicon wafer into the clamping area. When the side of the silicon wafer presses against the contact plate 16, the guide rod 17 slides outwards along the groove of the top block 15, and the return spring 18 is compressed, generating a reverse force to achieve elastic clamping of the silicon wafer. The pressure plate 13 is then rotated again to adjust the position of the top block 15. When the protective pad 19 of the top block 15 contacts the upper surface of the silicon wafer and undergoes slight deformation, bidirectional clamping and positioning are completed.

[0027] After sufficient coolant is injected into the water tank 1, the motor 6 driven by gear 501, the water pump 11, and the cooler 12 are started sequentially. The water pump 11 draws coolant from the water tank 1 and delivers it through the water pipe 10 to the rotary connector 9. The rotary connector 9 is connected to the distribution layer 8, and the coolant is then evenly distributed to each chamber of the cooling blades 7 through the distribution layer 8. The motor 6 drives the gear ring 4 to rotate via gear 501, causing the cooling blades 7, the distribution layer 8, and the clamping assembly to rotate synchronously. The rotary connector 9 ensures a continuous supply of coolant through dynamic sealing. During rotation, the coolant flowing inside the cooling blades 7 forms forced convection with the silicon wafer surface, assisting in the transfer of heat from the silicon wafer to the coolant, achieving uniform cooling.

[0028] After annealing, motor 6 is turned off, and pressure plate 13 is rotated in the reverse direction to raise top block 15, releasing the clamping of the silicon wafer. When the annealed silicon wafer is removed vertically, contact plate 16 automatically resets under the action of return spring 18, reserving space for the next loading. After inserting a new silicon wafer into bottom block 15, the above clamping process is repeated to enter the next cycle. Liquid level sensor 21 monitors the liquid level in water tank 1 in real time, and issues a liquid replenishment prompt through the control panel when the liquid level is lower than the safety threshold. When placing the equipment, the threaded feet of the stabilizing feet 22 are adjusted to compensate for uneven ground, ensuring stable horizontal operation of the equipment.

[0029] Although this disclosure has been shown and described with reference to specific exemplary embodiments thereof, those skilled in the art will understand that various changes in form and detail may be made to this disclosure without departing from the spirit and scope of the disclosure as defined by the appended claims and their equivalents. Therefore, the scope of this disclosure should not be limited to the above embodiments, but should be defined not only by the appended claims, but also by their equivalents.

Claims

1. An annealing support for monocrystalline silicon wafers, characterized by: Includes a water tank (1) and water pipes (10). The top of the water tank (1) is connected to several support rods (2). The top of all the support rods (2) is connected to a buffer layer (3). The top of the buffer layer (3) is rotatably connected to a gear ring (4). The side of the buffer layer (3) is connected to a mounting bracket (5). The bottom of the mounting bracket (5) is equipped with a motor (6). The output shaft of the motor (6) is connected to a gear (501). The gear (501) meshes with the gear ring (4). The top surface of the gear ring (4) is connected to cooling blades (7). The top of the cooling blades (7) is connected to a flow divider (8). The top of the flow divider (8) is rotatably connected to... There is a rotating connecting seat (9), the top of the rotating connecting seat (9) is connected to the bottom of the water tank (1) through the water pipe (10), the water pipe (10) is installed with a water pump (11) at one end inside the water tank (1), a cooler (12) is installed between the water tank (1) and the buffer layer (3), the top of the cooler (12) is connected to the buffer layer (3), the bottom of the cooler (12) is connected to the water tank (1), the rotating connecting seat (9) is connected to the diversion layer (8), the cooling blade (7) is provided with multiple placement intervals, and a clamping component for clamping single crystal silicon wafers is provided inside the cooling blade (7).

2. The annealing support for a single-crystal silicon wafer according to claim 1, characterized in that: The clamping assembly includes a connecting plate (14), a guide rod (17), and a return spring (18). The top of the diversion layer (8) is threaded with a pressure plate (13). Several connecting plates (14) are vertically slidably connected within the diversion layer (8). The bottom of the connecting plate (14) passes through the diversion layer (8) and is connected to a top block (15). Several top blocks (15) are connected to the top surface of the gear ring (4). The top blocks (15) are located at the top and bottom ends of the cooling blade (7). Guide rods (17) are slidably connected to the left and right sides of the top blocks (15). One end of the guide rod (17) passes through the top block (15) and is connected to a contact plate (16). The guide rod (17) is sleeved with a return spring (18). One end of the return spring (18) is connected to the top block (15), and the other end is connected to the contact plate (16).

3. The annealing support for a single-crystal silicon wafer according to claim 2, characterized in that: A protective pad (19) is laid inside the top block (15).

4. The annealing support for a single-crystal silicon wafer according to claim 3, characterized in that: The top of the pressure plate (13) is connected to several protrusions (20).

5. The annealing support for a single-crystal silicon wafer according to claim 4, characterized in that: A liquid level sensor (21) is installed inside the water tank (1).

6. The annealing support for a single-crystal silicon wafer according to claim 5, characterized in that: The bottom of the water tank (1) is connected to several stable feet (22).

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