Method for avoiding electrostatic chuck edge air hole arc discharge

Abstract

The invention discloses a method for avoiding electrostatic chuck edge air hole arc discharge, and belongs to the technical field of electrostatic chucks, the method comprises the following steps: S1, manufacturing an electrostatic chuck and pre-treating an air channel, manufacturing the electrostatic chuck and the air channel on the electrostatic chuck, and pre-treating the air channel; s2, preparation of an insulating adhesive: the insulating adhesive comprises a filler, an organic adhesive and an additive, and the ingredients are weighed, mixed and degassed; s3, uniformly coating the inner part of the gas path pore channel with an insulating adhesive to ensure that the insulating adhesive uniformly covers the inner part of the gas path pore channel; s4, the thickness of an adsorption layer on the surface of the electrostatic chuck is increased through a meltallizing process, and the electrical performance and corrosion resistance of the electrostatic chuck are improved; s5, carrying out mechanical grinding and polishing treatment on the surface of the adsorption layer and a gas path pore channel so as to improve the surface smoothness and reduce the flow resistance; and S6, sealing treatment is conducted on the surface of the adsorption layer, so that the electrostatic chuck achieves the mechanical performance and the insulating performance.

Description

Technical Field

[0001] The invention relates to the technical field of electrostatic chucks, and in particular to a method for avoiding arc discharge of air holes at the edge of an electrostatic chuck. Background Art

[0002] Electrostatic chuck (ESC) is a wafer clamping tool used in etching, ion implantation, cleaning and other harsh environment processes. Since the entire chamber is in a plasma environment, its structure and characteristics need to meet specific requirements to ensure that it can work efficiently and stably during the manufacturing process. The existing electrostatic chuck basic structure includes a base, an insulating layer, an electrode layer and an adsorption layer.

[0003] The air passage of the electrostatic chuck base forms air holes on the surface of the electrostatic chuck, which can provide precisely controlled airflow to maintain the stability of the wafer. However, in the application of electrostatic chucks, arc discharge in the air holes is a common and difficult problem. The air holes of the electrostatic chuck are susceptible to arc discharge in high-voltage electric fields and complex processing environments. This phenomenon will not only damage the electrostatic chuck, but may also cause damage to the wafer or other sensitive electronic devices being processed, affecting the product yield and the stability of the equipment.

[0004] In order to solve the problem of arc discharge, a variety of solutions have been proposed in the prior art, including adding ceramic components, redesigning the gas passages, and using anodizing processes to treat the gas passage holes. Although the above methods have alleviated the problem of arc discharge in the gas passage holes to a certain extent, there are still many limitations in industrial applications. The redesign of ceramic components and gas passages usually leads to higher manufacturing costs and process complexity, and although the melt spraying process is simple to operate, it is easily restricted in application due to the problem of pore diameter, and the melt spraying process is also prone to uneven coating problems, affecting the insulation effect. The coating thickness of anodizing is limited and is not easy to repair later.

[0005] Therefore, a simple and effective method is needed to avoid arc discharge of air holes on the edge of the electrostatic chuck. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a method for avoiding arc discharge of air holes at the edge of an electrostatic chuck, so as to solve the problem raised in the background technology.

[0007] In order to solve the above technical problems, the technical solution of the present invention is:

[0008] A method for avoiding arc discharge at an air hole on an edge of an electrostatic chuck, the method comprising:

[0009] S1: Pre-treatment of electrostatic chuck and gas channel, manufacturing electrostatic chuck and gas channel thereon, removing impurities and oxides on the inner wall of gas channel by pre-treatment of gas channel, so as to ensure the adhesion of subsequent coating and bonding;

[0010] S2: Preparation of insulating adhesive, which includes filler, organic binder and additives. The ingredients are weighed, mixed and degassed to finally obtain an insulating adhesive with good performance, which has good insulation, bonding strength and temperature resistance and meets the insulation requirements of the gas path;

[0011] S3: Evenly apply the insulating adhesive inside the gas channel to ensure that the insulating adhesive is evenly covered inside the gas channel to form an effective insulating coating to prevent arc discharge during operation and improve the overall mechanical strength and bonding strength;

[0012] S4: Use the spraying process to increase the thickness of the adsorption layer on the surface of the electrostatic chuck, improve its electrical properties and corrosion resistance, and thus improve the overall performance and service life of the electrostatic chuck;

[0013] S5: Mechanically grind and polish the surface of the adsorption layer and the gas channel to improve the surface finish and reduce the flow resistance;

[0014] S6: The surface of the adsorption layer is sealed to ensure that the electrostatic chuck has mechanical and insulation properties, ensuring reliable operation of the equipment under high load and high temperature conditions.

[0015] Preferably, the air path hole pretreatment in step S1 includes using ultrasonic cleaning to remove surface pollutants and oxide layers, drying after cleaning, the drying temperature is 50-100°C, the drying time is 12-48 hours, and then the inner wall of the air path hole is polished, and the surface roughness Ra after polishing is 4-6μm to improve the adhesion of the insulating adhesive.

[0016] Preferably, the electrostatic chuck manufactured in step S1 comprises a metal base, an insulating layer, an electrode layer and an adsorption layer, wherein the insulating layer, the electrode layer and the adsorption layer of the electrostatic chuck are all manufactured by a spraying process, wherein the thickness of the adsorption layer is 30 to 300 μm;

[0017] The metal base is made of any one of metal aluminum, metal titanium, aluminum alloy, titanium alloy, and stainless steel, and the insulating layer includes any one of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3, or a mixture of two or more thereof;

[0018] The adsorption layer includes any one of the ceramic materials Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3; the electrode layer includes any one of tungsten, nickel, and molybdenum, or a mixture of two or more thereof; and the sprayed layer includes any one of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3, or a mixture of two or more thereof.

[0019] Preferably, in step S2, the mass proportion of the filler is 60-75%, the mass proportion of the organic binder is 20-40%, and the mass proportion of the additive is 5-20%, so as to ensure its insulation, stability and smooth surface characteristics;

[0020] The filler is a ceramic powder, and the ceramic powder is any one of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3. The ceramic powder in the insulating adhesive is the same as the ceramic material used in the adsorption layer, and the particle size of the ceramic powder is 0.1 to 40 μm;

[0021] The organic binder is an epoxy resin or a polyimide resin, which can provide the basic mechanical strength and toughness of the coating under high temperature working environment, ensure the firm adhesion of the ceramic powder on the surface of the substrate, and have excellent electrical insulation performance;

[0022] The additives are dispersants, toughening agents, rheology modifiers, defoamers and diluents.

[0023] Preferably, in step S2, the insulating adhesive is mixed by:

[0024] First add the organic binder, then gradually add the ceramic powder, and at the same time add the dispersant and rheology modifier to ensure that the particles are evenly dispersed to form a well-mixed pre-slurry;

[0025] Then add the toughening agent and defoamer to the well-mixed pre-slurry and stir to avoid introducing too many bubbles. Finally, add the diluent to adjust the viscosity of the insulating adhesive to achieve a more uniform mixing state for coating.

[0026] The pre-slurry is first stirred and mixed at a speed of 2000-4000 rpm for 15-30 min, and after adding the toughening agent and defoaming agent, the slurry is stirred at a speed of 300-1000 rpm for 30 min-2 h.

[0027] The insulating adhesive has a viscosity of 5000 to 30000 cps and is uniformly mixed and dispersed within this range to maintain excellent physical properties and surface gloss characteristics.

[0028] Preferably, in step S2, the degassing treatment includes: mixing the filler, the organic binder and the additive and placing them in a vacuum degassing device, and treating them at a vacuum degree of 0.002 to 0.05 MPa for 5 to 15 minutes to completely eliminate the bubbles inside the paste and ensure the density and uniformity of the final coating.

[0029] Preferably, in step S3, the thickness of the insulating coating is 50 to 150 μm, and the insulating coating is ensured to be densely coated inside the gas path of the electrostatic chuck. After coating, the electrostatic chuck is placed in a vacuum curing furnace and cured at 30 to 120° C. for 2 to 12 hours to cure the insulating coating and achieve the required mechanical strength and insulation performance, so that its HV hardness is greater than or equal to 850 kgf / mm 2 , Ra≤0.2μm, porosity is 1~4%.

[0030] Preferably, in step S4, the spraying process is any one of atmospheric plasma spraying, flame spraying, arc spraying, high-velocity oxygen-fuel spraying, cold spraying, and vacuum plasma spraying;

[0031] The thickness of the adsorption layer on the surface of the electrostatic chuck is increased by using a spraying process, so that the thickness of the adsorption layer is 200-800 μm, and the porosity of the adsorption layer is 1-4%.

[0032] Preferably, in step S5, a CNC grinder is used to perform mechanical grinding and polishing on the surface of the adsorption layer, and a micro-grinding tool is used to grind the air path holes to meet the requirements of the air path hole diameter and hole depth. After grinding, the air path is rinsed with pure water and ground until the thickness of the adsorption layer is 50 to 400 μm, and Ra ≤ 0.2 μm.

[0033] Preferably, in step S6, a sealant is used to uniformly coat the surface of the adsorption layer, wherein the sealant is a resin sealant, and the sealant is coated by brushing, dipping or dripping.

[0034] The above technical solution has the following beneficial effects:

[0035] 1. By coating a specially designed insulating adhesive inside the gas channel and curing it, the present invention greatly improves the overall insulation performance of the electrostatic chuck. This process can effectively avoid arc discharge, especially in high temperature and high pressure environments, ensuring the safe operation of the equipment;

[0036] 2. Compared with the previous complex processes and process steps, the use of insulating adhesives simplifies the way to prevent arc discharge from pores, avoids the inefficiency caused by multiple treatments in traditional processes, and greatly reduces environmental impact and process difficulty;

[0037] 3. Maintaining appropriate roughness on the inner wall of the gas path before applying the insulating adhesive significantly improves the bonding force and mechanical strength between the coating and the substrate, thereby extending the service life of the electrostatic chuck;

[0038] 4. For the problems of peeling and cracking of the sprayed layer on the inner wall of the gas path of the electrostatic chuck, it is easier to use insulating adhesive for repair and coating;

[0039] 5. Compared with the sprayed layer, the coating coated with insulating adhesive has a lower porosity, ensuring the reliability of the coating in a high-demand environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of a cross-sectional structure of a portion of an electrostatic chuck of the present invention whose air passage holes are not coated with adhesive;

[0041] Figure 2 It is a schematic cross-sectional structure diagram of the gas path duct coated with the adhesive of the present invention;

[0042] Figure 3 The figure is a schematic cross-sectional structural diagram of the gas path holes at the edge of the electrostatic chuck after a complete process of the present invention. DETAILED DESCRIPTION

[0043] The specific embodiments of the present invention are further described below in conjunction with the accompanying drawings. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] Example 1

[0045] refer to Figure 1 to Figure 3 , a method for avoiding arc discharge of air holes at the edge of an electrostatic chuck, comprising the following steps:

[0046] S1: Pre-processing the electrostatic chuck 1 and the gas path duct 2, manufacturing the electrostatic chuck 1 and the gas path duct 2 thereon, removing impurities and oxides on the inner wall of the gas path duct 2 by pre-processing the gas path duct 2, so as to ensure the adhesion of subsequent coating and bonding. At the same time, the manufacturing of the electrostatic chuck 1 ensures the stability and functionality of its structure, laying a good foundation for subsequent processes;

[0047] The pretreatment of the gas path duct 2 includes using ultrasonic cleaning to remove surface pollutants and oxide layers, drying after cleaning, the drying temperature is 50-100°C, the drying time is 12-48h, and then the inner wall of the gas path duct 2 is polished, and the surface roughness Ra after polishing is 4-6μm to improve the adhesion of the insulating adhesive;

[0048] The electrostatic chuck 1 manufactured as above comprises a metal base, an insulating layer 3, an electrode layer 4 and an adsorption layer 5, wherein the insulating layer 3, the electrode layer 4 and the adsorption layer 5 of the electrostatic chuck 1 are all manufactured by a spraying process, wherein the thickness of the adsorption layer 5 is 30 to 300 μm;

[0049] The metal base of the electrostatic chuck 1 is made of any one of metal aluminum, metal titanium, aluminum alloy, titanium alloy, and stainless steel, and the insulating layer 3 is made of any one of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3, or a mixture of two or more thereof;

[0050] The preparation material of the above-mentioned adsorption layer 5 includes any one of the ceramic materials Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3; the preparation material of the electrode layer 4 includes any one of tungsten, nickel, and molybdenum, or a mixture of two or more thereof; the preparation material of the thermal spraying layer includes any one of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3, or a mixture of two or more thereof;

[0051] S2: Preparation of insulating adhesive, the insulating adhesive includes filler, organic binder and additives, the ingredients are weighed, mixed and degassed, and finally an insulating adhesive with good performance is obtained, which has good insulation, bonding strength and temperature resistance, and meets the insulation requirements of the gas path channel 2;

[0052] The insulating adhesive includes fillers, organic binders and additives, with the fillers accounting for 60-75% by mass, the organic binders accounting for 20-40% by mass, and the additives accounting for 5-20% by mass, to ensure its insulation, stability and smooth surface characteristics;

[0053] The filler is a ceramic powder, and the ceramic powder is any one of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3. The ceramic powder in the insulating adhesive is the same as the ceramic material used in the adsorption layer 5, and the particle size of the ceramic powder used in the filler is 0.1 to 40 μm;

[0054] The organic binder is epoxy resin or polyimide resin, which can provide the basic mechanical strength and toughness of the coating under high temperature working environment, ensure the firm adhesion of ceramic powder on the surface of the substrate, and have excellent electrical insulation performance;

[0055] Additives include dispersants, toughening agents, rheology modifiers, defoamers, and diluents;

[0056] The above-mentioned mixing method of the insulating adhesive comprises the following steps:

[0057] First add the organic binder, then gradually add the ceramic powder, and at the same time add the dispersant and rheology modifier to ensure that the particles are evenly dispersed to form a well-mixed pre-slurry;

[0058] Then add the toughening agent and defoamer to the well-mixed pre-slurry and stir to avoid introducing too many bubbles. Finally, add the diluent to adjust the viscosity of the insulating adhesive to achieve a more uniform mixing state for coating.

[0059] The stirring speed of the pre-slurry is 2000-4000 rpm and the stirring time is 15-30 min. After adding the toughening agent and the defoaming agent, the stirring speed of the slurry is 300-1000 rpm and the stirring time is 30 min-2 h.

[0060] The viscosity of the insulating adhesive is 5000-30000cps, and it is evenly mixed and dispersed within this range to maintain excellent physical properties and surface gloss characteristics;

[0061] The degassing treatment includes: mixing the filler, the organic binder and the additive and placing them in a vacuum degassing device, and treating them at a vacuum degree of 0.002 to 0.05 MPa for 5 to 15 minutes to completely eliminate the bubbles in the paste and ensure the density and uniformity of the final coating;

[0062] S3: evenly coating the insulating adhesive inside the gas path hole 2, ensuring that the insulating adhesive evenly covers the gas path hole 2, forming an effective insulating coating 6, preventing arc discharge during operation, and improving the overall mechanical strength and bonding strength;

[0063] The thickness of the insulating coating 6 is 50-150 μm. The insulating coating 6 is ensured to be densely coated inside the gas path 2 of the electrostatic chuck 1. After coating, the electrostatic chuck 1 is placed in a vacuum curing furnace and cured at 30-120° C. for 2-12 hours to cure the insulating coating 6 and achieve the required mechanical strength and insulation performance, so that its HV hardness is greater than or equal to 850 kgf / mm 2 , surface roughness Ra≤0.2μm, porosity 1~4%;

[0064] S4: using a spraying process to increase the thickness of the adsorption layer 5 on the surface of the electrostatic chuck 1 to form a secondary spraying adsorption layer 7, thereby improving its electrical properties and corrosion resistance, thereby improving the overall performance and service life of the electrostatic chuck 1;

[0065] The above-mentioned spraying process is any one of atmospheric plasma spraying, flame spraying, arc spraying, high-velocity oxygen-fuel spraying, cold spraying, and vacuum plasma spraying;

[0066] Using a thermal spraying process to increase the thickness of the adsorption layer 5 on the surface of the electrostatic chuck 1, so that the thickness of the adsorption layer 5 is 200-800 μm, and the porosity of the adsorption layer 5 is 1-4%;

[0067] S5: mechanically grinding and polishing the surface of the adsorption layer 5 and the gas channel 2 to improve the surface finish and reduce the flow resistance;

[0068] The surface of the adsorption layer 5 is mechanically ground and polished using a CNC grinder, and the gas path hole 2 is ground using a micro-grinding tool to meet the requirements of the gas path hole diameter and hole depth. After grinding, it is rinsed with pure water until the thickness of the adsorption layer 5 is 50-400 μm and the surface roughness Ra ≤ 0.2 μm;

[0069] S6: performing sealing treatment on the surface of the adsorption layer 5 so that the electrostatic chuck 1 achieves mechanical and insulation properties and ensures reliable operation of the device under high load and high temperature conditions; using a sealant to evenly coat the surface of the adsorption layer 5, wherein the sealant is a resin sealant, and the sealant is applied by brushing, dipping or dripping;

[0070] The inside of the gas path channel 2 on the surface of the electrostatic chuck 1 needs to be cleaned to remove its pollutants and oxidation layer to ensure that the surface is clean and oil-free. The insulating layer 3, electrode layer 4 and adsorption layer 5 of the electrostatic chuck 1 are prepared by the spraying process. The part of the gas path channel 2 that needs to be coated with the insulating adhesive maintains a certain roughness. The prepared insulating adhesive is evenly coated on the inner wall surface of the gas path hole, and then cured under appropriate conditions to achieve the required coating thickness to ensure the bonding strength between the coating and the gas path channel and the mechanical strength and insulation performance of the coating. Finally, the spraying process is used to thicken the adsorption layer 5 on the surface of the electrostatic chuck 1, and the adsorption layer 5 on the surface of the electrostatic chuck 1 and the gas path channel 2 are ground and polished, which can effectively avoid arc discharge at the gas path channel 2;

[0071] The present invention significantly improves the overall insulation performance of the electrostatic chuck 1 by coating a specially designed insulating adhesive inside the gas channel 2 and curing it. This process can effectively avoid arc discharge, especially in high temperature and high pressure environments, and ensure the safe operation of the equipment.

[0072] Compared with the previous complex processes and process steps, the use of insulating adhesives simplifies the way to prevent arc discharge from pores, avoids the inefficiency caused by multiple treatments in traditional processes, and greatly reduces environmental impact and process difficulty;

[0073] Maintaining an appropriate roughness on the inner wall of the gas path duct 2 before applying the insulating adhesive significantly improves the bonding force and mechanical strength between the coating and the substrate, thereby extending the service life of the electrostatic chuck 1;

[0074] For the problem of peeling and cracking of the sprayed layer on the inner wall of the gas channel 2 of the electrostatic chuck 1, it is easier to repair and coat it with insulating adhesive.

[0075] Compared with the sprayed layer, the coating coated with insulating adhesive has a lower porosity, which ensures the reliability of the coating in a high-demand environment;

[0076] The technical solution of the present application can effectively reduce the risk of arc discharge at the edge of the gas path channel 2, significantly improving the insulation performance and durability of the electrostatic chuck 1. In addition, the process of the present invention is simple and highly operable, and is suitable for the manufacture of various types of electrostatic chucks 1.

[0077] Example 2

[0078] A method for avoiding arc discharge of air holes at the edge of an electrostatic chuck 1, comprising the following steps:

[0079] S1: Pre-processing the electrostatic chuck 1 and the gas path duct 2, manufacturing the electrostatic chuck 1 and the gas path duct 2 thereon, removing impurities and oxides on the inner wall of the gas path duct 2 by pre-processing the gas path duct 2, so as to ensure the adhesion of subsequent coating and bonding. At the same time, the manufacturing of the electrostatic chuck 1 ensures the stability and functionality of its structure, laying a good foundation for subsequent processes;

[0080] Among them, the above-mentioned pretreatment of the gas path channel 2 includes using ultrasonic cleaning to remove surface pollutants and oxide layers, and drying after cleaning, the drying temperature is 50°C or 100°C. In other implementations of this embodiment, the drying temperature can be 75°C, the drying time is 12h or 48h, and in other implementations of this embodiment, the drying time can also be 24h, and then the inner wall of the gas path channel 2 is polished, and the surface roughness Ra after polishing is 4μm or 6μm. In other implementations of this embodiment, the surface roughness can also be 5μm, so as to improve the adhesion of the insulating adhesive;

[0081] The electrostatic chuck 1 manufactured as above comprises a metal base, an insulating layer 3, an electrode layer 4 and an adsorption layer 5. The insulating layer 3, the electrode layer 4 and the adsorption layer 5 of the electrostatic chuck 1 are all manufactured by a spraying process, wherein the thickness of the adsorption layer 5 is 30 μm or 300 μm. In other implementations of this embodiment, the thickness of the adsorption layer 5 may also be 150 μm.

[0082] The metal base of the electrostatic chuck 1 is made of any one of metal aluminum, metal titanium, aluminum alloy, titanium alloy, and stainless steel, which can be selected according to actual needs. The preparation material of the insulating layer 3 includes any one of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3, or a mixture of two thereof. In other implementations of this embodiment, the preparation material of the insulating layer 3 includes a mixture of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3;

[0083] The preparation material of the above-mentioned adsorption layer 5 includes any one of the ceramic materials Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3, which is selected according to needs. The preparation material of the electrode layer 4 includes any one of tungsten, nickel, and molybdenum or a mixture of two of them. In other implementations of this embodiment, the preparation material of the electrode layer 4 includes tungsten, nickel, and molybdenum. The preparation material of the sprayed layer includes any one of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and a mixture of two of them. The preparation material of the sprayed layer includes a mixture of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3;

[0084] S2: Preparation of insulating adhesive, the insulating adhesive includes filler, organic binder and additives, the ingredients are weighed, mixed and degassed, and finally an insulating adhesive with good performance is obtained, which has good insulation, bonding strength and temperature resistance, and meets the insulation requirements of the gas path channel 2;

[0085] The insulating adhesive includes a filler, an organic binder and an additive, wherein the mass proportion of the filler is 60-75%, the mass proportion of the organic binder is 20-40%, and the mass proportion of the additive is 5-20%. The total mass proportion of the three is within 100%, and the selection is made according to the actual situation. In other implementations of this embodiment, the mass proportion of the filler is 60%, the mass proportion of the organic binder is 25%, and the mass proportion of the additive is 15%, so as to ensure its insulation, stability and smooth surface characteristics;

[0086] The filler is a ceramic powder, and the ceramic powder is any one of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3. The ceramic powder in the insulating adhesive is the same as the ceramic material used in the adsorption layer 5. The particle size of the ceramic powder used in the filler is 0.1 μm or 40 μm. In other implementations of this embodiment, the particle size of the ceramic powder used in the filler is 20 μm.

[0087] The organic binder is epoxy resin or polyimide resin, which can provide the basic mechanical strength and toughness of the coating under high temperature working environment, ensure the firm adhesion of ceramic powder on the surface of the substrate, and have excellent electrical insulation performance;

[0088] Additives include dispersants, toughening agents, rheology modifiers, defoamers, and diluents;

[0089] The above-mentioned mixing method of the insulating adhesive comprises the following steps:

[0090] First add the organic binder, then gradually add the ceramic powder, and at the same time add the dispersant and rheology modifier to ensure that the particles are evenly dispersed to form a well-mixed pre-slurry;

[0091] Then add the toughening agent and defoamer to the well-mixed pre-slurry and stir to avoid introducing too many bubbles. Finally, add the diluent to adjust the viscosity of the insulating adhesive to achieve a more uniform mixing state for coating.

[0092] Wherein, when the pre-slurry is stirred and mixed, the stirring speed at this time is 2000rpm or 4000rpm, and the stirring time is 15min or 30min. In other embodiments of this embodiment, the stirring speed of the pre-slurry is 3000rpm, and the stirring time is 20min. After the toughening agent and the defoaming agent are added, the stirring speed of the slurry is 300rpm or 1000rpm, and the stirring time is 30min or 2h. In other embodiments of this embodiment, after the toughening agent and the defoaming agent are added, the stirring speed of the slurry is 700rpm, and the stirring time is 1h.

[0093] The viscosity of the insulating adhesive is 5000cps or 30000cps. In other implementations of this embodiment, the viscosity of the insulating adhesive is 15000cps, and is uniformly mixed and dispersed within this range to maintain excellent physical properties and surface gloss characteristics;

[0094] The degassing treatment includes: mixing the filler, the organic binder and the additive and placing them in a vacuum degassing device, and treating them at a vacuum degree of 0.002MPa or 0.05MPa for 5min or 15min to completely eliminate the bubbles in the paste and ensure the density and uniformity of the final coating;

[0095] S3: evenly coating the insulating adhesive inside the gas path hole 2, ensuring that the insulating adhesive evenly covers the gas path hole 2, forming an effective insulating coating 6, preventing arc discharge during operation, and improving the overall mechanical strength and bonding strength;

[0096] The thickness of the insulating coating 6 is 50 μm or 150 μm. The insulating coating 6 is ensured to be densely coated inside the gas path 2 of the electrostatic chuck 1. After coating, the electrostatic chuck 1 is placed in a vacuum curing furnace and cured at 30° C. or 120° C. for 2 hours or 12 hours to cure the insulating coating 6 and achieve the required mechanical strength and insulation performance, so that its HV hardness is greater than or equal to 850 kgf / mm 2 , the Ra of the insulating coating 6 is 0.2 μm, and the porosity is 1% or 4%;

[0097] S4: using a thermal spraying process to increase the thickness of the adsorption layer 5 on the surface of the electrostatic chuck 1, thereby improving its electrical properties and corrosion resistance, thereby improving the overall performance and service life of the electrostatic chuck 1;

[0098] The above-mentioned spraying process is any one of atmospheric plasma spraying, flame spraying, arc spraying, high-velocity oxygen-fuel spraying, cold spraying, and vacuum plasma spraying;

[0099] The thickness of the adsorption layer 5 on the surface of the electrostatic chuck 1 is increased by a thermal spraying process, so that the thickness of the adsorption layer 5 is 200 μm or 800 μm. In other implementations of this embodiment, the thickness of the adsorption layer 5 is 500 μm, and the porosity of the adsorption layer 5 is 1-4%;

[0100] S5: mechanically grinding and polishing the surface of the adsorption layer 5 and the gas channel 2 to improve the surface finish and reduce the flow resistance;

[0101] The surface of the adsorption layer 5 is mechanically ground and polished using a CNC grinder, and the gas path hole 2 is ground using a micro-grinding tool to meet the requirements of the gas path hole diameter and hole depth. After grinding, it is rinsed with pure water until the thickness of the adsorption layer 5 is 50 μm or 400 μm, and the Ra of the adsorption layer 5 is 0.2 μm;

[0102] S6: performing sealing treatment on the surface of the adsorption layer 5 so that the electrostatic chuck 1 achieves mechanical properties and insulation properties, ensuring reliable operation of the device under high load and high temperature conditions; using a sealant to evenly coat the surface of the adsorption layer 5, wherein the sealant is a resin sealant, and the sealant is applied by brushing, dipping or dripping;

[0103] The inside of the gas path channel 2 on the surface of the electrostatic chuck 1 needs to be cleaned to remove its pollutants and oxidation layer to ensure that the surface is clean and oil-free. The insulating layer 3, electrode layer 4 and adsorption layer 5 of the electrostatic chuck 1 are prepared by the spraying process. The part of the gas path channel 2 that needs to be coated with the insulating adhesive maintains a certain roughness. The prepared insulating adhesive is evenly coated on the inner wall surface of the gas path hole, and then cured under appropriate conditions to achieve the required coating thickness to ensure the bonding strength between the coating and the gas path channel and the mechanical strength and insulation performance of the coating. Finally, the spraying process is used to thicken the adsorption layer 5 on the surface of the electrostatic chuck 1, and the adsorption layer 5 on the surface of the electrostatic chuck 1 and the gas path channel 2 are ground and polished, which can effectively avoid arc discharge at the gas path channel 2;

[0104] The present invention significantly improves the overall insulation performance of the electrostatic chuck 1 by coating a specially designed insulating adhesive inside the gas channel 2 and curing it. This process can effectively avoid arc discharge, especially in high temperature and high pressure environments, and ensure the safe operation of the equipment.

[0105] Compared with the previous complex processes and process steps, the use of insulating adhesives simplifies the way to prevent arc discharge from pores, avoids the inefficiency caused by multiple treatments in traditional processes, and greatly reduces environmental impact and process difficulty;

[0106] Maintaining an appropriate roughness on the inner wall of the gas path duct 2 before applying the insulating adhesive significantly improves the bonding force and mechanical strength between the coating and the substrate, thereby extending the service life of the electrostatic chuck 1;

[0107] For the problem of peeling and cracking of the sprayed layer on the inner wall of the gas channel 2 of the electrostatic chuck 1, it is easier to repair and coat it with insulating adhesive.

[0108] Compared with the sprayed layer, the coating coated with insulating adhesive has a lower porosity, which ensures the reliability of the coating in a high-demand environment;

[0109] The technical solution of the present application can effectively reduce the risk of arc discharge at the edge of the gas path channel 2, significantly improving the insulation performance and durability of the electrostatic chuck 1. In addition, the process of the present invention is simple and highly operable, and is suitable for the manufacture of various types of electrostatic chucks 1.

[0110] Example 3

[0111] Select an aluminum alloy base electrostatic chuck 1 with a gas channel 2 having a pore diameter of 0.8 mm and a hole depth of 1.3 mm, and use ultrasonic cleaning to clean the inner wall and surface of the gas channel 2, using pure water as the cleaning material for 15 minutes;

[0112] A mask is used to cover the pores of the gas path channel 2, and #40 corundum material is used for sandblasting, with a roughness Ra of 6 μm. Alumina is used for the materials of the insulating layer 3 and the adsorption layer 5, and tungsten powder is used for the electrode layer 4. The insulating layer 3 is prepared on the surface of the metal base by using an atmospheric plasma spraying process, and the thickness of the insulating layer 3 is 150 μm. The pores are covered on the surface of the prepared insulating layer 3 with a mask, and the electrode layer 4 is prepared by using an atmospheric plasma spraying process, and the thickness of the electrode layer 4 is 30 μm. The mask is removed, and the surface of the electrostatic chuck 1 is sprayed to form an adsorption layer 5, and the thickness of the adsorption layer 5 is 60 μm.

[0113] The insulating adhesive is configured according to the proportions: alumina powder accounts for 55wt% of the overall formula, bisphenol A epoxy resin accounts for 35wt% of the overall formula, polyacrylate accounts for 3wt% of the overall formula, liquid polyurethane toughening agent usually accounts for 6wt% of the total amount of epoxy resin, siloxane defoamer accounts for 0.2wt% of the total system, and diethylene glycol butyl ether accounts for 8wt% of the total amount of epoxy resin;

[0114] In a stirring tank, first add bisphenol A epoxy resin and stir at 3000rpm, then gradually add alumina powder, and add polyacrylate and epoxy resin plasticizer at the same time to ensure uniform dispersion of particles, stir for 30min until a uniform pre-slurry is formed, add liquid polyurethane toughening agent, stir slowly at 300rpm to avoid the introduction of bubbles, add siloxane defoamer, continue to stir slowly, and finally add diethylene glycol butyl ether to adjust the viscosity of the insulating adhesive to 9000cps;

[0115] The mixed insulating adhesive was placed in a vacuum degassing device and treated at a vacuum degree of 0.002 MPa for 5 minutes to completely eliminate the bubbles inside the paste;

[0116] Use a precision coating instrument to evenly coat the inside of the pores of the gas path channel 2. During the coating process, keep the slurry force balanced and control the coating thickness at 100μm. Ensure that the coating is densely and evenly coated inside the gas path channel 2 of the electrostatic chuck 1. Place the electrostatic chuck 1 in a vacuum curing furnace and cure it at 80℃ for 10 hours to cure the coating and achieve the required mechanical strength and insulation performance, so that HV≥850kgf / mm 2 , surface roughness Ra≤0.2μm, porosity 1~3%;

[0117] Mechanical grinding and polishing treatment of the surface of the adsorption layer 5 and the gas path 2, using a CNC grinder to grind and polish the surface of the adsorption layer 5, the thickness of the adsorption layer 5 is 280μm, Ra≤0.2μm. Use a micro-grinding tool to carefully grind the gas path hole so that the gas path hole diameter is 0.5mm;

[0118] Finally, epoxy resin sealant is used to seal the surface of the adsorption layer 5 so that the electrostatic chuck 1 can achieve the required insulation performance.

[0119] Example 4

[0120] Based on Example 3, other conditions are the same, except that a different formulation of insulating adhesive is used: 50wt% yttrium oxide powder, bisphenol A epoxy resin accounts for 40wt% of the overall formulation, polyacrylate accounts for 3wt% of the overall formulation. Liquid polyurethane toughening agent is usually 5wt% of the total amount of epoxy resin, siloxane defoamer accounts for 0.3wt% of the total system, diethylene glycol butyl ether accounts for 6wt% of the total amount of epoxy resin, and the configured insulating adhesive is treated at a vacuum degree of 0.01MPa for 5min;

[0121] After the initial spraying of the adsorption layer 5, the pore opening is coated with an insulating adhesive, and the coating thickness of the inner wall of the gas path 2 is optimized to 75 μm. The vacuum is cured at 120 ° C for 3 hours to make HV ≥ 850 kgf / mm 2 , the surface roughness Ra≤0.2μm, the porosity is 1-2%, and then the final spraying and grinding and polishing of the adsorption layer 5 are carried out.

[0122] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments are made without departing from the principles and spirit of the present invention, and still fall within the scope of protection of the present invention.

Claims

1. A method for avoiding arc discharge at the edge of an electrostatic chuck, characterized in that: The method comprises: S1: Pre-treatment of electrostatic chuck and gas channel, manufacturing electrostatic chuck and gas channel thereon, removing impurities and oxides on the inner wall of gas channel by pre-treatment of gas channel, so as to ensure the adhesion of subsequent coating and bonding; S2: Preparation of insulating adhesive, which includes filler, organic binder and additives. The ingredients are weighed, mixed and degassed to finally obtain an insulating adhesive with good performance, which has good insulation, bonding strength and temperature resistance and meets the insulation requirements of the gas path; S3: Evenly apply the insulating adhesive inside the gas channel to ensure that the insulating adhesive is evenly covered inside the gas channel to form an effective insulating coating to prevent arc discharge during operation and improve the overall mechanical strength and bonding strength; S4: Use the spraying process to increase the thickness of the adsorption layer on the surface of the electrostatic chuck, improve its electrical properties and corrosion resistance, and thus improve the overall performance and service life of the electrostatic chuck; S5: Mechanically grind and polish the surface of the adsorption layer and the gas channel to improve the surface finish and reduce the flow resistance; S6: The surface of the adsorption layer is sealed to ensure that the electrostatic chuck has mechanical and insulation properties, ensuring reliable operation of the equipment under high load and high temperature conditions.

2. A method for avoiding arc discharge at the edge pores of an electrostatic chuck according to claim 1, characterized in that: The air path hole pretreatment in step S1 includes using ultrasonic cleaning to remove surface pollutants and oxide layers, drying after cleaning, the drying temperature is 50-100°C, the drying time is 12-48 hours, and then the inner wall of the air path hole is polished, and the surface roughness Ra after polishing is 4-6μm to improve the adhesion of the insulating adhesive.

3. A method for avoiding arc discharge at the edge pores of an electrostatic chuck according to claim 2, characterized in that: The electrostatic chuck manufactured in step S1 comprises a metal base, an insulating layer, an electrode layer and an adsorption layer, wherein the insulating layer, the electrode layer and the adsorption layer of the electrostatic chuck are all manufactured by a spraying process, wherein the thickness of the adsorption layer is 30 to 300 μm; The metal base is made of any one of metal aluminum, metal titanium, aluminum alloy, titanium alloy, and stainless steel, and the insulating layer includes any one of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3, or a mixture of two or more thereof; The adsorption layer includes any one of the ceramic materials Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3; the electrode layer includes any one of tungsten, nickel, and molybdenum, or a mixture of two or more thereof; and the sprayed layer includes any one of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3, or a mixture of two or more thereof.

4. A method for avoiding arc discharge at the edge pores of an electrostatic chuck according to claim 1, characterized in that: In the step S2, the mass proportion of the filler is 60-75%, the mass proportion of the organic binder is 20-40%, and the mass proportion of the additive is 5-20%, so as to ensure its insulation, stability and smooth surface characteristics; The filler is a ceramic powder, and the ceramic powder is any one of Al2O3, AlN, ZrO2, MgO, SiO2, SiC, Y2O3, and YF3. The ceramic powder in the insulating adhesive is the same as the ceramic material used in the adsorption layer, and the particle size of the ceramic powder is 0.1 to 40 μm; The organic binder is an epoxy resin or a polyimide resin, which can provide the basic mechanical strength and toughness of the coating under high temperature working environment, ensure the firm adhesion of the ceramic powder on the surface of the substrate, and have excellent electrical insulation performance; The additives are dispersants, toughening agents, rheology modifiers, defoamers and diluents.

5. A method for avoiding arc discharge at the edge pores of an electrostatic chuck according to claim 4, characterized in that: In step S2, the insulating adhesive is mixed by: First add the organic binder, then gradually add the ceramic powder, and at the same time add the dispersant and rheology modifier to ensure that the particles are evenly dispersed to form a well-mixed pre-slurry; Then add the toughening agent and defoamer to the well-mixed pre-slurry and stir to avoid introducing too many bubbles. Finally, add the diluent to adjust the viscosity of the insulating adhesive to achieve a more uniform mixing state for coating. The pre-slurry is first stirred and mixed at a speed of 2000-4000 rpm for 15-30 min, and after adding the toughening agent and defoaming agent, the slurry is stirred at a speed of 300-1000 rpm for 30 min-2 h. The insulating adhesive has a viscosity of 5000 to 30000 cps and is uniformly mixed and dispersed within this range to maintain excellent physical properties and surface gloss characteristics.

6. A method for avoiding arc discharge at the edge pores of an electrostatic chuck according to claim 1, characterized in that: In step S2, the degassing treatment includes: mixing the filler, the organic binder and the additive and placing them in a vacuum degassing device, and treating them at a vacuum degree of 0.002 to 0.05 MPa for 5 to 15 minutes to completely eliminate the bubbles in the paste and ensure the density and uniformity of the final coating.

7. A method for avoiding arc discharge at the edge of an electrostatic chuck according to claim 1, characterized in that: In the step S3, the thickness of the insulating coating is 50 to 150 μm, and the insulating coating is ensured to be densely coated inside the gas path of the electrostatic chuck. After coating, the electrostatic chuck is placed in a vacuum curing furnace and cured at 30 to 120° C. for 2 to 12 hours to cure the insulating coating and achieve the required mechanical strength and insulation performance, so that its HV hardness is greater than or equal to 850 kgf / mm 2 , Ra≤0.2μm, porosity is 1~4%.

8. A method for avoiding arc discharge at the edge pores of an electrostatic chuck according to claim 1, characterized in that: In step S4, the spraying process is any one of atmospheric plasma spraying, flame spraying, arc spraying, high-speed oxygen-fuel spraying, cold spraying, and vacuum plasma spraying; The thickness of the adsorption layer on the surface of the electrostatic chuck is increased by using a spraying process, so that the thickness of the adsorption layer is 200-800 μm, and the porosity of the adsorption layer is 1-4%.

9. A method for avoiding arc discharge at the edge pores of an electrostatic chuck according to claim 1, characterized in that: In step S5, a CNC grinder is used to perform mechanical grinding and polishing on the surface of the adsorption layer, and a micro-grinding tool is used to grind the air path holes to meet the requirements of the air path hole diameter and hole depth. After grinding, the air path holes are rinsed with pure water and ground until the thickness of the adsorption layer is 50 to 400 μm, and Ra ≤ 0.2 μm.

10. A method for avoiding arc discharge at the edge of an electrostatic chuck according to claim 1, characterized in that: In the step S6, a sealant is used to evenly coat the surface of the adsorption layer, wherein the sealant is a resin sealant, and the sealant is applied by brushing, dipping or dripping.

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