A multi-group mica sheet series heating type wafer heating disc structure

Abstract

The application discloses a multi-group mica sheet series connection heating type wafer heating disc structure, and aims to solve the problem of poor wafer heating uniformity of a heating disc, adopts a multi-region independent heating mode, and controls a complex system and has high cost. The application comprises a mounting plate and a heat conduction plate, a plurality of groups of mica heating sheets are installed in a radial interval between the mounting plate and the heat conduction plate, the mica heating sheets are circumferentially and uniformly arranged, all the mica heating sheets are connected in series in a same loop, and a plurality of groups of negative pressure adsorption grooves are arranged on the upper surface of the heat conduction plate. The heating disc has good temperature uniformity during a heating process, is favorable for guaranteeing the processing quality of the wafer, and the heating process of the heat conduction plate does not need to be independently controlled through multiple channels, so that the structure is simplified and the cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of semiconductor processing technology, and more specifically, to a multi-set mica sheet series heating wafer heating disk structure. Background Technology

[0002] In semiconductor manufacturing processes, such as chemical vapor deposition (CVD), physical vapor deposition (PVD), atomic layer deposition (ALD), and etching, precise and uniform temperature control of the wafer is often required. The heating plate (also known as a heating stage or chuck) is a core component that supports and heats the wafer; its heating uniformity, response speed, and long-term stability directly affect the wafer processing quality.

[0003] The common heating method for wafer heating pads is electric heating wire heating, such as the wafer heating pad disclosed in Chinese Patent Application No. 2025118451780. This method uses an electric heating wire to heat the pad. However, a drawback is that the thermal expansion coefficients of the resistance wire and the substrate material are different, which can easily lead to insulation layer damage or localized overheating under prolonged high temperatures, affecting the heating uniformity of the pad. To improve the heating uniformity, multi-zone independent heating methods are also used, with each zone controlled by a separate temperature control channel. This approach can improve the heating uniformity, but the control system is complex and requires numerous temperature sensors and multi-channel power output modules, resulting in high costs. Summary of the Invention

[0004] To overcome the above shortcomings, the present invention provides a multi-group mica sheet series heating wafer heating disk structure, which has good heating uniformity, simple structure and low cost.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a multi-group mica sheet series heating wafer heating plate structure, including a mounting plate and a heat-conducting plate, wherein several rings of mica heating sheets are radially spaced between the mounting plate and the heat-conducting plate, each ring of mica heating sheets is evenly distributed circumferentially, all mica heating sheets are connected in series in the same circuit, and several rings of negative pressure adsorption grooves are provided on the upper surface of the heat-conducting plate.

[0006] In this application, several rings of mica heating elements are radially spaced between the mounting plate and the heat-conducting plate. Each ring of mica heating elements is evenly distributed circumferentially, ensuring uniform heating across the heat-conducting plate and guaranteeing uniform heating at all locations. All mica heating elements are connected in series in the same circuit, requiring only one set of power input terminals. This eliminates the need for multi-channel independent control, simplifying the structure and reducing costs. A negative pressure adsorption tank connected to a vacuum through-hole generates negative pressure to adsorb and position the wafer mounted on the heat-conducting plate. The heating plate exhibits good temperature uniformity during heating, which helps ensure wafer processing quality. Furthermore, the heating process of the heat-conducting plate does not require multi-channel independent control, further simplifying the structure and reducing costs.

[0007] Preferably, a temperature sensor is mounted on the mounting plate.

[0008] The temperature of the mounting plate is detected by a temperature sensor, making it easy to control the heating temperature.

[0009] Preferably, a temperature protection switch is connected to the circuit in which the mica heating elements are connected in series.

[0010] When the heat-conducting plate overheats abnormally, the entire series circuit is cut off by a temperature protection switch to achieve safety protection.

[0011] Preferably, the bottom of the negative pressure adsorption tank is provided with an air suction hole, which is connected to an air suction pipe, and an air supply switch is installed on the air suction pipe.

[0012] The ventilation switch controls the opening and closing of the vacuum line, facilitating the adsorption and positioning of the wafer.

[0013] Preferably, a mica mounting groove corresponding to and adapted to the mica heating element is provided on the lower surface of the heat-conducting plate, and the mica heating element is installed in the mica mounting groove.

[0014] The mica mounting slot facilitates the installation and positioning of the mica heating element.

[0015] Preferably, the mica heating element includes an upper mica sheet, a lower mica sheet, and a resistance wire, with the resistance wire installed between the upper and lower mica sheets.

[0016] When the resistance wire is energized, it generates heat and transfers the heat to the upper and lower mica sheets, causing the entire mica heating element to heat up, thereby heating the heat-conducting plate.

[0017] Preferably, the surface of the heat-conducting plate is subjected to hard anodizing treatment.

[0018] Hard anodizing treatment increases the corrosion resistance and wear resistance of the heat-conducting plate surface.

[0019] Preferably, the heating power of the mica heating elements increases sequentially from the inner ring to the outer ring.

[0020] Because the wafer edge dissipates heat quickly, the mica heating element near the edge of the heat-conducting plate has a high heating power to compensate for the temperature at the edge of the heat-conducting plate.

[0021] Preferably, the resistance wires of the several turns of mica heating elements are made of the same material and have the same thickness, with the length of the resistance wires increasing sequentially from the inner to the outer ring; or, the resistance wires of the several turns of mica heating elements are of the same length and thickness, with the resistivity of the resistance wires increasing sequentially from the inner to the outer ring.

[0022] By using different structural settings, the resistance of the mica heating element's resistance wire increases sequentially from the inner ring to the outer ring, thereby achieving a sequential increase in heating power from the inner ring to the outer ring.

[0023] Preferably, a heat-spreading air channel is provided inside the heat-conducting plate. The heat-spreading air channel extends continuously and completely covers the entire plane inside the heat-conducting plate. Heat-spreading air is introduced into the heat-spreading air channel and circulates within the heat-spreading air channel.

[0024] During the heating process of the mica heating element on the heat-conducting plate, the heat-dissipating airflow circulates along the heat-dissipating air channel. The heat-dissipating airflow exchanges heat with different positions on the heat-conducting plate, which is beneficial to the temperature uniformity of various positions on the heat-conducting plate and improves the temperature uniformity of the heat-conducting plate.

[0025] Compared with the prior art, the beneficial effects of the present invention are: (1) The heating plate has good temperature uniformity during the heating process, which is conducive to ensuring the processing quality of the wafer. Moreover, the heating process of the heat-conducting plate does not require multi-channel independent control, which is conducive to simplifying the structure and reducing costs; (2) The entire heating plate only needs one set of power control output and one temperature measurement feedback to realize the overall heating control, avoiding the complexity and high cost of multi-channel independent control system; (3) By adjusting the distribution mode and quantity of mica sheets in the heating plate or by adjusting the resistance value of each series mica sheet group, the theoretical temperature distribution curve of the wafer surface can be flexibly matched, which is especially conducive to compensating for the heat loss at the edge of the wafer; (4) All mica heating sheets are connected in the same circuit, and the current flowing through each group of mica heating sheets is the same. Therefore, the heating power is proportional to the resistance of each group. Through differentiated resistance design, high-precision partition power distribution can be achieved; (5) The mica heating sheet itself has excellent insulation and high temperature resistance performance. In the series mode, any group of open circuits will cause the whole heating to stop, which is easy to detect faults. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the present invention.

[0027] Figure 2 This is an exploded view of the present invention.

[0028] Figure 3 This is a structural diagram of the back of the heat-conducting plate of the present invention.

[0029] Figure 4 This is a structural diagram of the mica heating element of the present invention.

[0030] Figure 5 This is a structural diagram of the heat dissipation airway of the present invention.

[0031] Figure 6 This is a structural diagram of the airflow drive device of the present invention.

[0032] In the diagram: 1. Mounting plate, 2. Heat-conducting plate, 3. Mica heating element, 4. Mica mounting groove, 5. Negative pressure adsorption groove, 6. Temperature sensor, 7. Temperature protection switch, 8. Air intake hole, 9. Ventilation switch, 10. Upper mica sheet, 11. Lower mica sheet, 12. Resistance wire, 13. Ceramic adhesive, 14. Heat-spreading air passage, 15. Airflow drive device, 16. Housing, 17. Heat-spreading chamber, 18. Drive chamber, 19. Rotating shaft, 20. Drive blade, 21. Heat-spreading blade, 22. Air inlet, 23. Air extraction port, 24. Inlet, 25. Outlet. Detailed Implementation

[0033] The technical solution of the present invention will be further described in detail below through specific embodiments and with reference to the accompanying drawings: Example 1: A multi-set mica sheet series heating wafer heating disk structure (see...) Figure 1 , Figure 2 , Figure 3 , Figure 4 The system includes a mounting plate 1 and a heat-conducting plate 2. The heat-conducting plate 2 is made of a thermally conductive metal material, preferably aluminum alloy or aluminum nitride ceramic matrix composite metal. Several rings of mica heating elements 3 are radially spaced between the mounting plate 1 and the heat-conducting plate 2. Mica mounting grooves 4, corresponding to and adapted to the mica heating elements 3, are provided on the lower surface of the heat-conducting plate 2, and the mica heating elements 3 are installed in the mica mounting grooves 4. The mica mounting grooves 4 facilitate the installation and positioning of the mica heating elements 3. The upper surface of the heat-conducting plate 2 is the wafer bearing surface. Each ring of mica heating elements 3 is evenly distributed circumferentially, and all mica heating elements 3 are connected in series in the same circuit. Several rings of negative pressure adsorption grooves 5 are provided on the upper surface of the heat-conducting plate 2. The entire series circuit requires only one set of power input terminals, eliminating the need for multi-channel independent control.

[0034] The heat-conducting plate 2, as the disk that directly contacts the wafer, is made of 6-series aluminum alloy. The surface of the heat-conducting plate 2 undergoes hard anodizing treatment to increase its corrosion resistance and wear resistance. The working surface of the heat-conducting plate 2 has negative pressure adsorption grooves 5 for use with 12-inch and 8-inch wafers. The two sets of negative pressure adsorption grooves 5 can be controlled independently or used together.

[0035] The heat-conducting plate 2 has an inner ring mica mounting groove 4, a middle mica mounting groove 4, and an outer ring mica mounting groove 4 on its back. The three rings of mica mounting grooves 4 are evenly distributed on the heat-conducting plate 2 to ensure that the heat from the mica heating element 3 can be evenly distributed on the surface of the heat-conducting plate 2 during heating, thereby improving the temperature uniformity of the surface of the heat-conducting plate 2.

[0036] Temperature sensor 6 is installed on mounting plate 1 to detect the temperature of mounting plate 1, facilitating control of the heating temperature. A temperature protection switch 7 is connected to the series circuit of mica heating elements 3. When the heat-conducting plate 2 overheats abnormally, the temperature protection switch 7 cuts off the entire series circuit for safety protection. A suction hole 8 is provided at the bottom of the negative pressure adsorption tank 5, connected to a suction pipe. A vent switch 9 is installed on the suction pipe. The vent switch 9 controls the on / off state of the vacuum pipe, facilitating the adsorption and positioning of the wafer.

[0037] The mica heating element 3 comprises an upper mica sheet 10, a lower mica sheet 11, and a resistance wire 12, with the resistance wire 12 installed between the upper and lower mica sheets 10 and 11. The resistance wire 12 is arranged in a serpentine structure and is made of nickel-chromium alloy, an excellent resistive conductor and the most common material for resistance wire on the market. Ceramic adhesive 13 is placed between the upper and lower mica sheets 10 and 11 to bond the various parts of the mica heating element together, forming a complete mica heating element 3. It also serves to fix the resistance wire 12 and provide insulation. Both the upper and lower mica sheets 10 and 11 are made of phlogopite, possessing excellent high-temperature resistance (1000℃) and good insulation properties. The two ends of the resistance wire 12 are connected to conductors. The conductor core is made of nickel alloy, and the insulation layer is a mica braided layer, exhibiting good temperature resistance and being a commonly used high-temperature conductor. When the resistance wire 12 is energized, it generates heat and transfers the heat to the upper mica sheet 10 and the lower mica sheet 11, causing the entire mica heating plate 3 to heat up, thereby heating the heat-conducting plate 2.

[0038] The heating power of the multiple rings of mica heating elements 3 increases sequentially from the inner ring to the outer ring. Because the wafer edge dissipates heat quickly, the mica heating elements 3 near the edge of the heat-conducting plate 2 have a higher heating power to compensate for the temperature at the edge of the heat-conducting plate 2. The resistance wires 12 of the multiple rings of mica heating elements 3 are of the same material and thickness, and their length increases sequentially from the inner ring to the outer ring.

[0039] In this application, several rings of mica heating elements 3 are radially spaced between the mounting plate 1 and the heat-conducting plate 2. Each ring of mica heating elements 3 is evenly distributed circumferentially, ensuring uniform heating across the heat-conducting plate 2. All mica heating elements 3 are connected in series in the same circuit. This series circuit requires only one set of power input terminals, eliminating the need for multi-channel independent control, which simplifies the structure and reduces costs. The negative pressure adsorption tank 5 is connected to a vacuum through-hole, generating negative pressure to adsorb and position the wafer loaded on the heat-conducting plate 2. The heating plate exhibits good temperature uniformity during heating, which helps ensure the processing quality of the wafer. Furthermore, the heating process of the heat-conducting plate 2 does not require multi-channel independent control, further simplifying the structure and reducing costs.

[0040] Example 2: A multi-set mica sheet series heating wafer heating disk structure (see...) Figure 1 , Figure 2 , Figure 3 , Figure 4 The system includes a mounting plate 1 and a heat-conducting plate 2. The heat-conducting plate 2 is made of a thermally conductive metal material, preferably aluminum alloy or aluminum nitride ceramic matrix composite metal. Several rings of mica heating elements 3 are radially spaced between the mounting plate 1 and the heat-conducting plate 2. Mica mounting grooves 4, corresponding to and adapted to the mica heating elements 3, are provided on the lower surface of the heat-conducting plate 2, and the mica heating elements 3 are installed in the mica mounting grooves 4. The mica mounting grooves 4 facilitate the installation and positioning of the mica heating elements 3. The upper surface of the heat-conducting plate 2 is the wafer bearing surface. Each ring of mica heating elements 3 is evenly distributed circumferentially, and all mica heating elements 3 are connected in series in the same circuit. Several rings of negative pressure adsorption grooves 5 are provided on the upper surface of the heat-conducting plate 2. The entire series circuit requires only one set of power input terminals, eliminating the need for multi-channel independent control.

[0041] The heat-conducting plate 2, as the disk that directly contacts the wafer, is made of 6-series aluminum alloy. The surface of the heat-conducting plate 2 undergoes hard anodizing treatment to increase its corrosion resistance and wear resistance. The working surface of the heat-conducting plate 2 has negative pressure adsorption grooves 5 for use with 12-inch and 8-inch wafers. The two sets of negative pressure adsorption grooves 5 can be controlled independently or used together.

[0042] The heat-conducting plate 2 has an inner ring mica mounting groove 4, a middle mica mounting groove 4, and an outer ring mica mounting groove 4 on its back. The three rings of mica mounting grooves 4 are evenly distributed on the heat-conducting plate 2 to ensure that the heat from the mica heating element 3 can be evenly distributed on the surface of the heat-conducting plate 2 during heating, thereby improving the temperature uniformity of the surface of the heat-conducting plate 2.

[0043] Temperature sensor 6 is installed on mounting plate 1 to detect the temperature of mounting plate 1, facilitating control of the heating temperature. A temperature protection switch 7 is connected to the series circuit of mica heating elements 3. When the heat-conducting plate 2 overheats abnormally, the temperature protection switch 7 cuts off the entire series circuit for safety protection. A suction hole 8 is provided at the bottom of the negative pressure adsorption tank 5, connected to a suction pipe. A vent switch 9 is installed on the suction pipe. The vent switch 9 controls the on / off state of the vacuum pipe, facilitating the adsorption and positioning of the wafer.

[0044] The mica heating element 3 comprises an upper mica sheet 10, a lower mica sheet 11, and a resistance wire 12, with the resistance wire 12 installed between the upper and lower mica sheets 10 and 11. The resistance wire 12 is arranged in a serpentine structure and is made of nickel-chromium alloy, an excellent resistive conductor and the most common material for resistance wire on the market. Ceramic adhesive 13 is placed between the upper and lower mica sheets 10 and 11 to bond the various parts of the mica heating element together, forming a complete mica heating element 3. It also serves to fix the resistance wire 12 and provide insulation. Both the upper and lower mica sheets 10 and 11 are made of phlogopite, possessing excellent high-temperature resistance (1000℃) and good insulation properties. The two ends of the resistance wire 12 are connected to conductors. The conductor core is made of nickel alloy, and the insulation layer is a mica braided layer, exhibiting good temperature resistance and being a commonly used high-temperature conductor. When the resistance wire 12 is energized, it generates heat and transfers the heat to the upper mica sheet 10 and the lower mica sheet 11, causing the entire mica heating plate 3 to heat up, thereby heating the heat-conducting plate 2.

[0045] The heating power of the several rings of mica heating elements 3 increases sequentially from the inner ring to the outer ring. Because the wafer edge dissipates heat quickly, the mica heating elements 3 near the edge of the heat-conducting plate 2 have a higher heating power to compensate for the temperature at the edge of the heat-conducting plate 2. The resistance wires 12 of the several rings of mica heating elements 3 have the same length and thickness, and the resistivity of the resistance wires 12 increases sequentially from the inner ring to the outer ring.

[0046] In this application, several rings of mica heating elements 3 are radially spaced between the mounting plate 1 and the heat-conducting plate 2. Each ring of mica heating elements 3 is evenly distributed circumferentially, ensuring uniform heating across the heat-conducting plate 2. All mica heating elements 3 are connected in series in the same circuit. This series circuit requires only one set of power input terminals, eliminating the need for multi-channel independent control, which simplifies the structure and reduces costs. The negative pressure adsorption tank 5 is connected to a vacuum through-hole, generating negative pressure to adsorb and position the wafer loaded on the heat-conducting plate 2. The heating plate exhibits good temperature uniformity during heating, which helps ensure the processing quality of the wafer. Furthermore, the heating process of the heat-conducting plate 2 does not require multi-channel independent control, further simplifying the structure and reducing costs.

[0047] Example 3: A multi-set mica sheet series heating wafer heating disk structure (see...) Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6The system includes a mounting plate 1 and a heat-conducting plate 2. The heat-conducting plate 2 is made of a thermally conductive metal material, preferably aluminum alloy or aluminum nitride ceramic matrix composite metal. Several rings of mica heating elements 3 are radially spaced between the mounting plate 1 and the heat-conducting plate 2. Mica mounting grooves 4, corresponding to and adapted to the mica heating elements 3, are provided on the lower surface of the heat-conducting plate 2, and the mica heating elements 3 are installed in the mica mounting grooves 4. The mica mounting grooves 4 facilitate the installation and positioning of the mica heating elements 3. The upper surface of the heat-conducting plate 2 is the wafer bearing surface. Each ring of mica heating elements 3 is evenly distributed circumferentially, and all mica heating elements 3 are connected in series in the same circuit. Several rings of negative pressure adsorption grooves 5 are provided on the upper surface of the heat-conducting plate 2. The entire series circuit requires only one set of power input terminals, eliminating the need for multi-channel independent control.

[0048] The heat-conducting plate 2, as the disk that directly contacts the wafer, is made of 6-series aluminum alloy. The surface of the heat-conducting plate 2 undergoes hard anodizing treatment to increase its corrosion resistance and wear resistance. The working surface of the heat-conducting plate 2 has negative pressure adsorption grooves 5 for use with 12-inch and 8-inch wafers. The two sets of negative pressure adsorption grooves 5 can be controlled independently or used together.

[0049] The heat-conducting plate 2 has an inner ring mica mounting groove 4, a middle mica mounting groove 4, and an outer ring mica mounting groove 4 on its back. The three rings of mica mounting grooves 4 are evenly distributed on the heat-conducting plate 2 to ensure that the heat from the mica heating element 3 can be evenly distributed on the surface of the heat-conducting plate 2 during heating, thereby improving the temperature uniformity of the surface of the heat-conducting plate 2.

[0050] A temperature sensor 6 is installed on the mounting plate 1 to detect the temperature of the mounting plate 1, facilitating the control of the heating temperature. A temperature protection switch 7 is connected to the series circuit of the mica heating element 3. When the heat-conducting plate 2 overheats abnormally, the temperature protection switch 7 cuts off the entire series circuit for safety protection. An air suction hole 8 is provided at the bottom of the negative pressure adsorption tank 5, which is connected to an air suction pipe. A vent switch 9 is installed on the air suction pipe, which is connected to a vacuum pump. The vacuum pump can generate negative pressure by evacuating air. The vacuum pump is existing technology and will not be described in detail in this application. The vent switch 9 controls the on / off state of the vacuum pipe, facilitating the adsorption and positioning of the wafer.

[0051] The mica heating element 3 comprises an upper mica sheet 10, a lower mica sheet 11, and a resistance wire 12, with the resistance wire 12 installed between the upper and lower mica sheets 10 and 11. The resistance wire 12 is arranged in a serpentine structure and is made of nickel-chromium alloy, an excellent resistive conductor and the most common material for resistance wire on the market. Ceramic adhesive 13 is placed between the upper and lower mica sheets 10 and 11 to bond the various parts of the mica heating element together, forming a complete mica heating element 3. It also serves to fix the resistance wire 12 and provide insulation. Both the upper and lower mica sheets 10 and 11 are made of phlogopite, possessing excellent high-temperature resistance (1000℃) and good insulation properties. The two ends of the resistance wire 12 are connected to conductors. The conductor core is made of nickel alloy, and the insulation layer is a mica braided layer, exhibiting good temperature resistance and being a commonly used high-temperature conductor. When the resistance wire 12 is energized, it generates heat and transfers the heat to the upper mica sheet 10 and the lower mica sheet 11, causing the entire mica heating plate 3 to heat up, thereby heating the heat-conducting plate 2.

[0052] The heating power of the multiple rings of mica heating elements 3 increases sequentially from the inner ring to the outer ring. Because the wafer edge dissipates heat quickly, the mica heating elements 3 near the edge of the heat-conducting plate 2 have a higher heating power to compensate for the temperature at the edge of the heat-conducting plate 2. The resistance wires 12 of the multiple rings of mica heating elements 3 are of the same material and thickness, and their length increases sequentially from the inner ring to the outer ring.

[0053] A heat-spreading air channel 14 is provided inside the heat-conducting plate 2. The heat-spreading air channel 14 extends continuously and completely covers the entire internal plane of the heat-conducting plate 2. An inert heat-spreading airflow, such as helium, is introduced into the heat-spreading air channel 14, and the heat-spreading airflow circulates within the heat-spreading air channel 14. The heat-conducting plate 2 includes an upper plate and a lower plate that are sealed together. A mica mounting groove 4 is provided on the lower surface of the lower plate, the heat-spreading air channel 14 is provided on the lower surface of the upper plate, and a negative pressure adsorption groove 5 is provided on the upper surface of the upper plate. The heat-spreading air channel 14 extends circumferentially and forms a multi-ring structure, so that both ends of the heat-spreading air channel 14 extend to the outer wall of the heat-conducting plate 2. The heat-spreading air channel 14 is connected to an airflow driving device 15. The airflow drive device 15 includes a housing 16, a heat dissipation chamber 17 and a drive chamber 18 are provided inside the housing 16, a rotating shaft 19 is rotatably connected inside the housing 16, a drive blade 20 and a heat dissipation blade 21 are installed on the rotating shaft 19, the drive blade 20 is installed in the drive chamber 18 and the heat dissipation blade 21 is installed in the heat dissipation chamber 17, the housing 16 is provided with an air inlet 22 and an air outlet 23 communicating with the drive chamber 18, the air outlet 23 is connected to an air extraction device through a pipe, the housing 16 is provided with an inlet 24 and an outlet 25 communicating with the heat dissipation chamber 17, and the two ends of the heat dissipation air passage 14 are respectively connected to the inlet 24 and the outlet 25.

[0054] While the vacuum device vacuums the negative pressure adsorption tank 5 to adsorb the wafer, it also vacuums the drive cavity 18, thereby driving the drive blade 20 to rotate. The drive blade 20 drives the rotating shaft 19 and the heat-spreading blade 21 to rotate. The rotation of the heat-spreading blade 21 causes the heat-spreading airflow in the heat-spreading air passage 14 to circulate. The heat-spreading airflow exchanges heat with different positions of the heat-conducting plate 2, which is beneficial to the temperature uniformity of each position of the heat-conducting plate 2 and improves the temperature uniformity of the heat-conducting plate 2.

[0055] In this application, several rings of mica heating elements 3 are radially spaced between the mounting plate 1 and the heat-conducting plate 2. Each ring of mica heating elements 3 is evenly distributed circumferentially, ensuring uniform heating across the heat-conducting plate 2. All mica heating elements 3 are connected in series in the same circuit. This series circuit requires only one set of power input terminals, eliminating the need for multi-channel independent control, which simplifies the structure and reduces costs. The negative pressure adsorption tank 5 is connected to a vacuum through-hole, generating negative pressure to adsorb and position the wafer loaded on the heat-conducting plate 2. The heating plate exhibits good temperature uniformity during heating, which helps ensure the processing quality of the wafer. Furthermore, the heating process of the heat-conducting plate 2 does not require multi-channel independent control, further simplifying the structure and reducing costs.

[0056] Example 4: A multi-set mica sheet series heating wafer heating disk structure (see...) Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 The system includes a mounting plate 1 and a heat-conducting plate 2. The heat-conducting plate 2 is made of a thermally conductive metal material, preferably aluminum alloy or aluminum nitride ceramic matrix composite metal. Several rings of mica heating elements 3 are radially spaced between the mounting plate 1 and the heat-conducting plate 2. Mica mounting grooves 4, corresponding to and adapted to the mica heating elements 3, are provided on the lower surface of the heat-conducting plate 2, and the mica heating elements 3 are installed in the mica mounting grooves 4. The mica mounting grooves 4 facilitate the installation and positioning of the mica heating elements 3. The upper surface of the heat-conducting plate 2 is the wafer bearing surface. Each ring of mica heating elements 3 is evenly distributed circumferentially, and all mica heating elements 3 are connected in series in the same circuit. Several rings of negative pressure adsorption grooves 5 are provided on the upper surface of the heat-conducting plate 2. The entire series circuit requires only one set of power input terminals, eliminating the need for multi-channel independent control.

[0057] The heat-conducting plate 2, as the disk that directly contacts the wafer, is made of 6-series aluminum alloy. The surface of the heat-conducting plate 2 undergoes hard anodizing treatment to increase its corrosion resistance and wear resistance. The working surface of the heat-conducting plate 2 has negative pressure adsorption grooves 5 for use with 12-inch and 8-inch wafers. The two sets of negative pressure adsorption grooves 5 can be controlled independently or used together.

[0058] The heat-conducting plate 2 has an inner ring mica mounting groove 4, a middle mica mounting groove 4, and an outer ring mica mounting groove 4 on its back. The three rings of mica mounting grooves 4 are evenly distributed on the heat-conducting plate 2 to ensure that the heat from the mica heating element 3 can be evenly distributed on the surface of the heat-conducting plate 2 during heating, thereby improving the temperature uniformity of the surface of the heat-conducting plate 2.

[0059] Temperature sensor 6 is installed on mounting plate 1 to detect the temperature of mounting plate 1, facilitating control of the heating temperature. A temperature protection switch 7 is connected to the series circuit of mica heating elements 3. When the heat-conducting plate 2 overheats abnormally, the temperature protection switch 7 cuts off the entire series circuit for safety protection. A suction hole 8 is provided at the bottom of the negative pressure adsorption tank 5, connected to a suction pipe. A vent switch 9 is installed on the suction pipe. The vent switch 9 controls the on / off state of the vacuum pipe, facilitating the adsorption and positioning of the wafer.

[0060] The mica heating element 3 comprises an upper mica sheet 10, a lower mica sheet 11, and a resistance wire 12, with the resistance wire 12 installed between the upper and lower mica sheets 10 and 11. The resistance wire 12 is arranged in a serpentine structure and is made of nickel-chromium alloy, an excellent resistive conductor and the most common material for resistance wire on the market. Ceramic adhesive 13 is placed between the upper and lower mica sheets 10 and 11 to bond the various parts of the mica heating element together, forming a complete mica heating element 3. It also serves to fix the resistance wire 12 and provide insulation. Both the upper and lower mica sheets 10 and 11 are made of phlogopite, possessing excellent high-temperature resistance (1000℃) and good insulation properties. The two ends of the resistance wire 12 are connected to conductors. The conductor core is made of nickel alloy, and the insulation layer is a mica braided layer, exhibiting good temperature resistance and being a commonly used high-temperature conductor. When the resistance wire 12 is energized, it generates heat and transfers the heat to the upper mica sheet 10 and the lower mica sheet 11, causing the entire mica heating plate 3 to heat up, thereby heating the heat-conducting plate 2.

[0061] The heating power of the several rings of mica heating elements 3 increases sequentially from the inner ring to the outer ring. Because the wafer edge dissipates heat quickly, the mica heating elements 3 near the edge of the heat-conducting plate 2 have a higher heating power to compensate for the temperature at the edge of the heat-conducting plate 2. The resistance wires 12 of the several rings of mica heating elements 3 have the same length and thickness, and the resistivity of the resistance wires 12 increases sequentially from the inner ring to the outer ring.

[0062] A heat-spreading air channel 14 is provided inside the heat-conducting plate 2. The heat-spreading air channel 14 extends continuously and completely covers the entire internal plane of the heat-conducting plate 2. An inert heat-spreading airflow, such as helium, is introduced into the heat-spreading air channel 14, and the heat-spreading airflow circulates within the heat-spreading air channel 14. The heat-conducting plate 2 includes an upper plate and a lower plate that are sealed together. A mica mounting groove 4 is provided on the lower surface of the lower plate, the heat-spreading air channel 14 is provided on the lower surface of the upper plate, and a negative pressure adsorption groove 5 is provided on the upper surface of the upper plate. The heat-spreading air channel 14 extends circumferentially and forms a multi-ring structure, so that both ends of the heat-spreading air channel 14 extend to the outer wall of the heat-conducting plate 2. The heat-spreading air channel 14 is connected to an airflow driving device 15. The airflow drive device 15 includes a housing 16, a heat dissipation chamber 17 and a drive chamber 18 are provided inside the housing 16, a rotating shaft 19 is rotatably connected inside the housing 16, a drive blade 20 and a heat dissipation blade 21 are installed on the rotating shaft 19, the drive blade 20 is installed in the drive chamber 18 and the heat dissipation blade 21 is installed in the heat dissipation chamber 17, the housing 16 is provided with an air inlet 22 and an air outlet 23 communicating with the drive chamber 18, the air outlet 23 is connected to an air extraction device through a pipe, the housing 16 is provided with an inlet 24 and an outlet 25 communicating with the heat dissipation chamber 17, and the two ends of the heat dissipation air passage 14 are respectively connected to the inlet 24 and the outlet 25.

[0063] While the vacuum device vacuums the negative pressure adsorption tank 5 to adsorb the wafer, it also vacuums the drive cavity 18, thereby driving the drive blade 20 to rotate. The drive blade 20 drives the rotating shaft 19 and the heat-spreading blade 21 to rotate. The rotation of the heat-spreading blade 21 causes the heat-spreading airflow in the heat-spreading air passage 14 to circulate. The heat-spreading airflow exchanges heat with different positions of the heat-conducting plate 2, which is beneficial to the temperature uniformity of each position of the heat-conducting plate 2 and improves the temperature uniformity of the heat-conducting plate 2.

[0064] In this application, several rings of mica heating elements 3 are radially spaced between the mounting plate 1 and the heat-conducting plate 2. Each ring of mica heating elements 3 is evenly distributed circumferentially, ensuring uniform heating across the heat-conducting plate 2. All mica heating elements 3 are connected in series in the same circuit. This series circuit requires only one set of power input terminals, eliminating the need for multi-channel independent control, which simplifies the structure and reduces costs. The negative pressure adsorption tank 5 is connected to a vacuum through-hole, generating negative pressure to adsorb and position the wafer loaded on the heat-conducting plate 2. The heating plate exhibits good temperature uniformity during heating, which helps ensure the processing quality of the wafer. Furthermore, the heating process of the heat-conducting plate 2 does not require multi-channel independent control, further simplifying the structure and reducing costs.

[0065] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Other variations and modifications may be made without departing from the technical solutions described in the claims.

Claims

1. A multi-set mica sheet series-connected heating wafer heating disk structure, characterized in that, It includes a mounting plate and a heat-conducting plate. Several rings of mica heating elements are installed radially between the mounting plate and the heat-conducting plate. Each ring of mica heating elements is evenly distributed circumferentially. All mica heating elements are connected in series in the same circuit. Several rings of negative pressure adsorption grooves are set on the upper surface of the heat-conducting plate.

2. The multi-group mica sheet series heating wafer heating disk structure according to claim 1, characterized in that, A temperature sensor is mounted on the mounting plate.

3. The multi-group mica sheet series heating wafer heating disk structure according to claim 1, characterized in that, A temperature protection switch is connected to the circuit in which the mica heating elements are connected in series.

4. The multi-group mica sheet series heating wafer heating disk structure according to claim 1, characterized in that, The bottom of the negative pressure adsorption tank is equipped with an air intake hole, which is connected to an air intake pipe. An air supply switch is installed on the air intake pipe.

5. The multi-group mica sheet series heating wafer heating disk structure according to claim 1, characterized in that, A mica mounting groove corresponding to and adapted to the mica heating element is provided on the lower surface of the heat-conducting plate, and the mica heating element is installed in the mica mounting groove.

6. The multi-group mica sheet series heating wafer heating disk structure according to claim 1, characterized in that, The mica heating element consists of an upper mica sheet, a lower mica sheet, and a resistance wire, with the resistance wire installed between the upper and lower mica sheets.

7. The multi-group mica sheet series heating wafer heating disk structure according to claim 1, characterized in that, The surface of the heat-conducting plate is subjected to hard anodizing treatment.

8. The multi-group mica sheet series heating wafer heating disk structure according to claim 1, characterized in that, The heating power of the mica heating elements increases sequentially from the inner ring to the outer ring.

9. The multi-group mica sheet series heating wafer heating disk structure according to claim 8, characterized in that, The resistance wires of several turns of mica heating elements are made of the same material and have the same thickness, with the length of the resistance wires increasing from the inner to the outer ring; or, the resistance wires of several turns of mica heating elements are of the same length and thickness, with the resistivity of the resistance wires increasing from the inner to the outer ring.

10. A multi-set mica sheet series heating wafer heating disk structure according to any one of claims 1 to 9, characterized in that, A heat-spreading air channel is set inside the heat-conducting plate. The heat-spreading air channel extends continuously and completely covers the entire plane inside the heat-conducting plate. Heat-spreading air flows into the heat-spreading air channel and circulates within the heat-spreading air channel.

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