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CN-121974709-A - Sintering method of alumina electrostatic chuck

CN121974709ACN 121974709 ACN121974709 ACN 121974709ACN-121974709-A

Abstract

The invention discloses a sintering method of an alumina electrostatic chuck, which belongs to the technical field of electrostatic chucks and comprises the steps of S1, preparing an insulating layer matrix by using a raw material and a multilayer structure, depositing an electrode layer on the insulating layer matrix, coating alumina nano powder on the electrode layer to form a dielectric layer, spraying a silicon carbide coating on the surface of the dielectric layer to form the multilayer structure, S2, placing the multilayer structure in a vacuum sintering furnace for primary sintering by primary sintering, S3, performing secondary sintering on the multilayer structure after primary sintering by adopting a pulse discharge plasma sintering technology, cooling after secondary sintering, S4, integrating heat-conducting glue attaching and cooling base on the bottom of the insulating layer matrix after secondary sintering of the multilayer structure, coating heat-conducting glue on the bottom of the insulating layer matrix, pressing the insulating layer matrix with the cooling base to prepare the electrostatic chuck, and performing plasma cleaning on the surface of the electrostatic chuck, and S5, performing high-pressure corona treatment on the electrostatic chuck by performance optimization treatment.

Inventors

  • LI JUN
  • CHENG LONG
  • SHI ZHEYUAN

Assignees

  • 君原电子科技(海宁)有限公司

Dates

Publication Date
20260505
Application Date
20251231

Claims (8)

  1. 1.A method of sintering an alumina electrostatic chuck, the method comprising the steps of: s1, preparation of raw materials and multilayer structure Preparing an insulating layer matrix, namely selecting high-purity alumina ceramic powder, adding 0.5-1.0% of insulating auxiliary agent, mixing, and preparing the insulating layer matrix with the thickness of 2-3 mm through a dry pressing molding process; depositing an electrode layer, namely depositing a metal electrode layer on the surface of the insulating layer substrate by adopting a magnetron sputtering or physical vapor deposition technology, wherein the thickness of the metal electrode layer is controlled to be 0.5-1 mu m; Preparing a dielectric layer, namely coating alumina nano powder on the electrode layer to form the dielectric layer, wherein the thickness of the dielectric layer is 10-15 mu m; Coating a silicon carbide coating on the surface of the dielectric layer to form a multilayer structure, wherein the thickness of the silicon carbide coating is 1-2 mu m so as to enhance the wear resistance; s2, sintering once Placing the multilayer structure in a vacuum sintering furnace, vacuumizing to a pressure of less than or equal to 5Pa, heating to 650-700 ℃ at a speed of 3 ℃ per minute, and preserving heat for 2 hours to realize atomic-level diffusion bonding of the electrode layer and the dielectric layer, so as to avoid layering; S3, secondary sintering Performing secondary sintering on the primary sintered multilayer structure by adopting a pulse discharge plasma sintering technology, setting the temperature to 1400-1500 ℃, heating the multilayer structure at a temperature rising rate of 50 ℃ per minute, applying dynamic pulse pressure of 30-50 MPa, wherein the frequency is 0.5Hz, the dynamic pulse pressure lasts for 10 seconds per cycle, the heat preservation time is 30 minutes, and performing step-down pressure reduction of 5MPa every 5 minutes during the period; cooling, namely cooling to room temperature at the speed of 2 ℃ per minute, so as to avoid thermal stress damage; s4, integrating heat-conducting glue attaching and cooling base Coating heat-conducting glue on the bottom of the insulating layer matrix after secondary sintering of the multilayer structure, and pressing with a cooling base to manufacture an electrostatic chuck; Surface treatment, namely performing plasma cleaning on the surface of the electrostatic chuck to remove residual impurities, and depositing a silicon nitride protective layer, wherein the thickness of the silicon nitride protective layer is 0.5-1 mu m, so that the plasma erosion resistance is enhanced; s5, performance optimization processing After sintering, the electrostatic chuck is subjected to high-voltage corona treatment, the electrostatic adsorption capacity of the surface is activated, and the surface flatness is ensured to be less than or equal to 0.1 mu m through precise grinding.
  2. 2. The method according to claim 1, wherein the high purity alumina ceramic powder in step S1 has a purity of 99.9% or more.
  3. 3. The method according to claim 1, wherein the insulating auxiliary agent in the step S1 is zirconia.
  4. 4. The method according to claim 1, wherein the metal electrode layer in the step S1 comprises molybdenum metal or tungsten metal.
  5. 5. The method according to claim 1, wherein the alumina nano powder in the step S1 has a particle size of 50nm or less.
  6. 6. The method according to claim 1, wherein the thermal conductivity of the thermal conductive paste in the step S4 is 5W/m·k or more.
  7. 7. The method according to claim 1, wherein in the step S4, the multi-layered structure is pressed against the cooling base, and the multi-layered structure is cured at a temperature of 120 ℃ under 10mpa for 1 hour.
  8. 8. The method according to claim 1, wherein in the step S5, the high voltage corona treatment comprises a high voltage corona treatment at a voltage of 5kV for 10 seconds.

Description

Sintering method of alumina electrostatic chuck Technical Field The invention relates to the technical field of electrostatic chucks, in particular to a sintering method of an alumina electrostatic chuck. Background The existing alumina ceramic electrostatic chuck sintering method has the common problems that in the traditional sintering process, the bonding strength of an electrode layer and a dielectric layer is insufficient, bubbles or layering are easy to generate, the adsorption is uneven, the plasma erosion resistance is poor, the sintering temperature is high, the time is long, the energy consumption is high, the production efficiency is low, and the cost is high due to the fact that complex equipment (such as hot isostatic pressing) is adopted in part of the process. Therefore, there is a need for an efficient, low cost sintering process to improve the overall performance of the electrostatic chuck. Disclosure of Invention The invention aims to provide a sintering method of an alumina electrostatic chuck to solve the problems in the background technology. In order to solve the technical problems, the technical scheme of the invention is as follows: a sintering method of an alumina electrostatic chuck, the sintering method comprising the steps of: s1, preparation of raw materials and multilayer structure Preparing an insulating layer matrix, namely selecting high-purity alumina ceramic powder, adding 0.5-1.0% of insulating auxiliary agent, mixing, and preparing the insulating layer matrix with the thickness of 2-3 mm through a dry pressing molding process; depositing an electrode layer, namely depositing a metal electrode layer on the surface of the insulating layer substrate by adopting a magnetron sputtering or physical vapor deposition technology, wherein the thickness of the metal electrode layer is controlled to be 0.5-1 mu m; Preparing a dielectric layer, namely coating alumina nano powder on the electrode layer to form the dielectric layer, wherein the thickness of the dielectric layer is 10-15 mu m; Coating a silicon carbide coating on the surface of the dielectric layer to form a multilayer structure, wherein the thickness of the silicon carbide coating is 1-2 mu m so as to enhance the wear resistance; s2, sintering once Placing the multilayer structure in a vacuum sintering furnace, vacuumizing to a pressure of less than or equal to 5Pa, heating to 650-700 ℃ at a speed of 3 ℃ per minute, and preserving heat for 2 hours to realize atomic-level diffusion bonding of the electrode layer and the dielectric layer, so as to avoid layering; S3, secondary sintering Performing secondary sintering on the primary sintered multilayer structure by adopting a pulse discharge plasma sintering technology, setting the temperature to 1400-1500 ℃, heating the multilayer structure at a temperature rising rate of 50 ℃ per minute, applying dynamic pulse pressure of 30-50 MPa, wherein the frequency is 0.5Hz, the dynamic pulse pressure lasts for 10 seconds per cycle, the heat preservation time is 30 minutes, and performing step-down pressure reduction of 5MPa every 5 minutes during the period; cooling, namely cooling to room temperature at the speed of 2 ℃ per minute, so as to avoid thermal stress damage; s4, integrating heat-conducting glue attaching and cooling base Coating heat-conducting glue on the bottom of the insulating layer matrix after secondary sintering of the multilayer structure, and pressing with a cooling base to manufacture an electrostatic chuck; Surface treatment, namely performing plasma cleaning on the surface of the electrostatic chuck to remove residual impurities, and depositing a silicon nitride protective layer, wherein the thickness of the silicon nitride protective layer is 0.5-1 mu m, so that the plasma erosion resistance is enhanced; s5, performance optimization processing After sintering, the electrostatic chuck is subjected to high-voltage corona treatment, the electrostatic adsorption capacity of the surface is activated, and the surface flatness is ensured to be less than or equal to 0.1 mu m through precise grinding. Preferably, the purity of the high purity alumina ceramic powder in the step S1 is 99.9% or more. Preferably, the insulating auxiliary agent in the step S1 is zirconia. Preferably, the metal electrode layer in the step S1 includes molybdenum metal or tungsten metal. Preferably, the particle size of the alumina nano powder in the step S1 is 50nm or less. Preferably, the thermal conductivity coefficient of the thermal conductive adhesive in the step S4 is 5W/m·k or more. Preferably, in the step S4, when the multi-layer structure is pressed against the cooling base, the pressure is 10mpa, and the heat preservation and solidification are performed for 1 hour at the temperature of 120 ℃. Preferably, in the step S5, the high voltage corona treatment includes a high voltage corona treatment at a voltage of 5kV for 10 seconds. By adopting the technical scheme, the method has