A fully enclosed mica heating base for a plasma etching machine

Abstract

A fully enclosed mica heating base for a plasma etching machine, comprising a heating base body, a mica heating sheet, a ceramic heat insulation plate and a high-temperature resistant heat insulation adapter sealing joint. The mica heating sheet and the ceramic heat insulation plate are arranged inside the heating base body, and the high-temperature resistant heat insulation adapter sealing joint is arranged on the heating base body. The fully enclosed mica heating base of the present invention realizes the function of heating the wafer and the polyimide electrostatic chuck placed on the surface by controlling the heat distribution generated by the multi-zone temperature-controlled heating wires etched and formed inside two mica sheets and making the working surface of the heating base uniformly heat through heat conduction.

Description

Technical Field

[0001] The present invention belongs to the field of semiconductors, and particularly relates to a fully enclosed mica heating base for a plasma etcher. Background Art

[0002] The heating base is a key component in the production process of semiconductor manufacturing equipment. When manufacturing semiconductor wafers in integrated circuit technology, rapid heating and very uniform temperature are required. Only when the heating speed is fast and the surface temperature distribution is uniform can the production efficiency be improved. Due to the manufacturing process limitations of the previous tubular electric heating tubes, it was difficult for the original heating base to meet higher uniformity requirements. Moreover, the heating base using tubular electric heating tubes has a large self-heat capacity and a relatively thick thickness, making it impossible to be installed in some cavities. It takes a long time to cool down, and the space in the vacuum chamber is compact. There is an urgent need for a heater that can quickly change the working temperature and has higher uniformity to change the current situation. Summary of the Invention

[0003] The invention aims to provide a fully enclosed mica heating base for a plasma etcher, which solves the above technical problems.

[0004] In order to achieve the above technical objectives and meet the above technical requirements, the technical solution adopted by the invention is: a fully enclosed mica heating base for a plasma etcher, characterized in that: it includes a heating base main body, mica heating sheets, a ceramic heat insulation plate, and a high-temperature resistant heat insulation transfer sealing joint. The mica heating sheets and the ceramic heat insulation plate are arranged inside the heating base main body, and the high-temperature resistant heat insulation transfer sealing joint is arranged on the heating base main body; the heating base main body includes an upper cover, a lower cover, a high-temperature resistant sealing joint, fixed threaded holes, and plugs; the mica heating sheets include an upper mica sheet, a lower mica sheet, heating sheet installation grooves, heating wires, and heating sheets; the ceramic heat insulation plate includes a ceramic heat insulation plate main body, positioning and locking ceramic screws, locking screws, and wire lead-out grooves; the ceramic heat insulation plate main body presses the mica heating sheets through the locking screws and cooperates with the heating base main body through the positioning and locking ceramic screws. The upper mica sheet and the lower mica sheet are fixed in cooperation through the heating sheet installation grooves; the heating wires extend out from the wire lead-out grooves and cooperate with the high-temperature resistant heat insulation transfer sealing joint.

[0005] As a preferred technical solution: the plugs and the high-temperature resistant sealing structure are arranged on the lower cover.

[0006] As a preferred technical solution: the high-temperature resistant and heat-insulating transfer and sealing joint includes a titanium alloy body, a sealing groove for high-temperature O-rings, a sealing groove for low-temperature O-rings, a thin-wall structure, and a high-temperature resistant adhesive bonding part for vacuum sealing; a sealing groove for low-temperature O-rings is provided on the titanium alloy body on the side of the high-temperature resistant adhesive bonding part for vacuum sealing, and a sealing groove for high-temperature O-rings is provided on the other side of the titanium alloy body; the thin-wall structure is formed by welding.

[0007] As a preferred technical solution: the high-temperature resistant sealing structure is in sealing cooperation with the high-temperature resistant and heat-insulating transfer and sealing joint.

[0008] As a preferred technical solution: the heating sheet includes an inner area heating sheet, a middle area heating sheet, and an outer area heating sheet; the heating sheet is formed by etching.

[0009] The fully enclosed mica heating base of the present invention controls the heat distribution generated by the multi-zone temperature-controlled heating wires formed by etching inside the two mica sheets, and makes the working surface of the heating base uniformly heat through heat conduction, so as to realize the function of heating the wafer and the polyimide electrostatic chuck placed on the surface. Description of the Drawings

[0010] Figure 1 is a schematic structural diagram of the fully enclosed mica heating base;

[0011] Figure 2 is a schematic structural diagram of the heating base body in the fully enclosed mica heating base;

[0012] Figure 3 is a schematic structural diagram of the mica heating sheet in the fully enclosed mica heating base;

[0013] Figure 4 is a schematic structural diagram of the heating sheet in the fully enclosed mica heating base

[0014] Figure 5 is a schematic structural diagram of the ceramic heat-insulating plate in the fully enclosed mica heating base;

[0015] Figure 6 is a schematic structural diagram of the high-temperature resistant and heat-insulating transfer and sealing joint in the fully enclosed mica heating base;

[0016] In the figure: 1. Heating base body; 1-1. Upper cover; 1-2. Lower cover; 1-3. High-temperature resistant sealing joint; 1-4. Fixed threaded hole; 1-5. Plug; 2. Mica heating sheet; 2-1. Upper mica sheet; 2-3. Lower mica sheet; 2-3. Heating sheet installation groove; 2-4. Heating wire; 2-5. Heating sheet; 2-6. Inner area heating sheet; 2-7. Middle area heating sheet; 2-8. Outer area heating sheet; 3. Ceramic heat insulation board; 3-1. Ceramic heat insulation board body; 3-2. Positioning and locking ceramic screw; 3-3. Locking screw; 3-4. Wire lead-out groove; 4. High-temperature resistant heat insulation transfer sealing joint; 4-1. Titanium alloy body; 4-2. Sealing groove for high-temperature O-ring; 4-3. Sealing groove for low-temperature O-ring; 4-4. Thin-wall structure; 4-5. High-temperature resistant adhesive part for vacuum sealing. Detailed implementation method

[0017] A fully enclosed mica heating base for a plasma etching machine, characterized in that it includes a heating base body 1, a mica heating sheet 2, a ceramic heat insulation board 3, and a high-temperature resistant heat insulation transfer sealing joint 4. The mica heating sheet 2 and the ceramic heat insulation board 3 are arranged inside the heating base body 1, and the high-temperature resistant heat insulation transfer sealing joint 4 is arranged on the heating base body 1; the heating base body 1 includes an upper cover 1-1, a lower cover 1-2, a high-temperature resistant sealing joint 1-3, a fixed threaded hole 1-4, and a plug 1-5; the mica heating sheet 2 includes an upper mica sheet 2-1, a lower mica sheet 2-2, a heating sheet installation groove 2-3, a heating wire 2-4, and a heating sheet 2-5; the ceramic heat insulation board 3 includes a ceramic heat insulation board body 3-1, a positioning and locking ceramic screw 3-2, a locking screw 3-3, and a wire lead-out groove 3-4; the ceramic heat insulation board body 3-1 presses the mica heating sheet 2 through the locking screw 3-3 and cooperates with the heating base body 1 through the positioning and locking ceramic screw 3-2. The upper mica sheet 2-1 and the lower mica sheet 2-2 are fixed in cooperation through the heating sheet installation groove 2-3; the heating wire 2-4 extends out from the wire lead-out groove 3-4 and cooperates with the high-temperature resistant heat insulation transfer sealing joint 4.

[0018] The plug 1-5 and the high-temperature resistant sealing structure 1-3 are arranged on the lower cover 1-2. The high-temperature resistant heat-insulating adapter sealing joint 4 includes a titanium alloy body 4-1, a sealing groove 4-2 for high-temperature O-rings, a sealing groove 4-3 for low-temperature O-rings, a thin-wall structure 4-4, and a high-temperature resistant adhesive bonding part 4-5 for vacuum sealing; on the titanium alloy body 4-1 on the side of the high-temperature resistant adhesive bonding part 4-5 for vacuum sealing, there is arranged a sealing groove 4-3 for low-temperature O-rings, and on the other side of the titanium alloy body 4-1, there is arranged a sealing groove 4-2 for high-temperature O-rings; the thin-wall structure 4-4 is formed by welding. The high-temperature resistant sealing structure 1-3 is in sealing cooperation with the high-temperature resistant heat-insulating adapter sealing joint 4. The heating sheet 2-5 includes an inner area heating sheet 2-6, a middle area heating sheet 2-7, and an outer area heating sheet 2-8.

[0019] During specific implementation: After the heating sheet is powered on, it generates heat, which is conducted to the wafer or the polyimide electrostatic chuck through the upper mica sheet and the upper cover made of aluminum alloy or stainless steel. Through the design of the three-zone heating sheet, the heating temperature of the wafer or the polyimide electrostatic chuck can be accurately adjusted. At the same time, the structure of the internal multi-layer sealing design has a lower outgassing rate during operation, and the plasma is blocked outside, so the working life of the mica heating sheet is longer. At the same time, there are air guide grooves on the surface of the heating base to reduce the sliding of the wafer, and the hard oxide layer on the surface can reduce the wear of the heating base.

[0020] The above embodiments are merely descriptions made to clearly illustrate the present invention, rather than limitations on the implementation manners. For those skilled in the art, based on the above description, other different forms of changes or variations can be made. It is not necessary and impossible to enumerate all the implementation manners here, and the obvious changes or variations derived therefrom still fall within the protection scope of the present invention.

Claims

1. A fully enclosed mica heating base for a plasma etching machine, characterized in that: It includes a heating base body (1), a mica heating sheet (2), a ceramic heat insulation plate (3), and a high-temperature resistant heat insulation adapter sealing joint (4). The mica heating sheet (2) and the ceramic heat insulation plate (3) are arranged inside the heating base body (1), and the high-temperature resistant heat insulation adapter sealing joint (4) is arranged on the heating base body (1). The heating base body (1) includes an upper cover (1-1), a lower cover (1-2), a high-temperature resistant sealing joint (1-3), fixed threaded holes (1-4), and a plug (1-5). The mica heating sheet (2) includes an upper mica sheet (2-1), a lower mica sheet (2-2), a heating sheet installation groove (2-3), heating wires (2-4), and a heating sheet (2-5). The ceramic heat insulation plate (3) includes a ceramic heat insulation plate main body (3-1), positioning and locking ceramic screws (3-2), locking screws (3-3), and a wire lead-out groove (3-4). The ceramic heat insulation plate main body (3-1) presses the mica heating sheet (2) through the locking screws (3-3) and cooperates with the heating base body (1) through the positioning and locking ceramic screws (3-2). The upper mica sheet (2-1) and the lower mica sheet (2-2) are fixedly matched through the heating sheet installation groove (2-3). The heating wires (2-4) extend out from the wire lead-out groove (3-4) and cooperate with the high-temperature resistant heat insulation adapter sealing joint (4). The heating base body (1) uses aluminum alloy or stainless steel with a thin-wall structure as the base to reduce heat loss during use. Positioning and installation holes for fixing the mica heating sheet are machined inside to ensure accurate positioning during mica sheet installation. Gas guiding grooves evenly distributed in a circular pattern are machined on the surface to prevent the wafer from sliding during use. A sealing joint with a sealing groove and high-temperature sealant for sealing the wire is designed at the position of the wire outlet on the base. This sealing area cooperates with an O-ring during the operation of the mica heating base, and there is a design of a sealing plug for vacuum pumping after assembly to avoid process gas corrosion of the internal heating sheet and prevent moisture absorption of the internal mica sheet, which affects the service life. The high-temperature resistant heat insulation adapter sealing joint (4) includes a titanium alloy main body (4-1), a sealing groove for high-temperature O-ring (4-2), a sealing groove for low-temperature O-ring (4-3), a thin-wall structure (4-4), and a high-temperature resistant adhesive bonding part for vacuum sealing (4-5). The sealing groove for low-temperature O-ring (4-3) is arranged on the titanium alloy main body (4-1) on the side of the high-temperature resistant adhesive bonding part for vacuum sealing (4-5), and the sealing groove for high-temperature O-ring (4-2) is arranged on the other side of the titanium alloy main body (4-1). The thin-wall structure (4-4) is formed by welding.

2. The all - enclosed mica heating base for a plasma etcher according to claim 1, wherein: The plug (1-5) and the high-temperature resistant sealing joint (1-3) are arranged on the lower cover (1-2).

3. The all - enclosed mica heating base for a plasma etching machine according to claim 1, characterized in that: The high-temperature resistant sealing joint (1-3) is in sealing cooperation with the high-temperature resistant heat insulation adapter sealing joint (4).

4. The fully enclosed mica heating base for a plasma etching machine according to claim 1, wherein: The heating sheet (2-5) includes an inner area heating sheet (2-6), a middle area heating sheet (2-7), and an outer area heating sheet (2-8). The heating sheet (2-5) is formed by etching.

5. The fully enclosed mica heating base for a plasma etching machine according to claim 1, wherein: The heating sheet (2-5) precisely calculates the temperature distribution trend and then adjusts the thickness distribution of the heating sheet; etching processing is carried out to form the heating sheet.

6. The all - enclosed mica heating base for a plasma etching machine according to claim 1, characterized in that: The mica heating sheet (2) is machined mechanically using a suction cup to ensure uniform thickness; grooves with different widths and depths for mating with the heating sheet (2-5) are machined on the upper mica sheet (2-1) and the lower mica sheet (2-2) with uniform thickness to ensure firm fixation of the heating sheet (2-5).

7. The all - enclosed mica heating base for a plasma etching machine according to claim 1, wherein: The ceramic heat insulation plate (3) is made of a machinable glass-ceramic plate and is turned to ensure a flatness of 0.05 mm.

8. The fully enclosed mica heating base for a plasma etching machine according to claim 1, characterized in that: The high-temperature heat insulation adapter sealing joint (4) has a main body made of an alloy with a low thermal conductivity; a thin-wall structure is used to reduce heat conduction; sealing grooves are machined and used in conjunction with an O-ring to isolate the external atmosphere from the process environment; high-temperature ceramic glue and glass are used to seal the wire to prevent air from entering the heating base.

9. The fully enclosed mica heating base for a plasma etching machine according to claim 1, wherein: The exterior of the heating base body is treated with hard anodizing to protect the non-oxidized areas and wires on the heating base, ensuring a high-temperature sealing effect and preventing the wires from being corroded by the tank solution.

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