Method for manufacturing an electrostatic chuck

• US 6,986,865 B2
• Filed: 07/10/2002
• Issued: 01/17/2006
• Est. Priority Date: 07/10/2002
• Status: Active Grant

• Current Assignee: Watlow Electric Manufacturing Company
• Original Assignee: Watlow Electric Manufacturing Company
• Inventors: Lin, Hongy, Smith, Jason Eugene, Laskowski, Thomas Michael
• Primary Examiner(s): Walls, Dionne A.
• Assistant Examiner(s): LYLES IRVING, CARMEN V
• Application Number:
  US10/192,803
• Publication Number:
  US 20040007800A1
• Time in Patent Office: 1,287 Days
• Field of Search: 264/614, 264/619, 264/618, 264/658, 419/11
• US Class Current: 264/619
• CPC Class Codes: B32B 2315/02 Ceramics
• CPC Class Codes: C04B 2235/3886 Refractory metal nitrides, e.g. vanadium nitride, tungsten nitride
• CPC Class Codes: C04B 2235/5436 micrometer sized, i.e. from 1 to 100 micron
• CPC Class Codes: C04B 2235/5445 submicron sized, i.e. from 0,1 to 1 micron
• CPC Class Codes: C04B 2235/604 Pressing at temperatures other than sintering temperatures
• CPC Class Codes: C04B 2235/658 Atmosphere during thermal treatment
• CPC Class Codes: C04B 2235/77 Density
• CPC Class Codes: C04B 2235/94 Products characterised by their shape
• CPC Class Codes: C04B 2237/343 Alumina or aluminates
• CPC Class Codes: C04B 35/117 Composites
• CPC Class Codes: C04B 35/645 Pressure sintering

Abstract

A method for manufacturing an electrostatic chuck is disclosed wherein a sintered ceramic body having a dielectric layer made from Alumina (Al2O2) and Titanium Nitride (TiN) having a specific range of particle size is heat treated in an oxygen-rich environment in order to produce a uniform dielectric layer having no pores or micro-cracks.

Claims

1. A method for manufacturing an electrostatic chuck comprising the steps of:

a) pouring a predetermined amount of an insulation material into a mold;

b) creating a hollow pathway through said insulation material;

c) pouring a predetermined amount of a conductive material into said hollow pathway to establish a conductive path;

d) pouring a predetermined amount of said conductive material on top of said insulation material and said conductive path to produce a compact;

e) removing said compact from said mold;

f) pressing said compact to form a compact structure;

g) sintering said compact structure to form a ceramic structure under a non-oxidative atmosphere; and

h) heat treating said compact ceramic structure in an oxygen-rich environment.

2. The method according to claim 1, wherein said insulation material comprises alumina.

3. The method according to claim 1, wherein said conductive material comprises a mixture of titanium nitride and alumina.

4. The method according to claim 1, wherein said step of pressing the compact further comprises using pressures ranging between 5,000-50,000 psi.

5. The method according to claim 1, wherein said step of sintering comprises a hot pressing procedure using a temperature range of between 1,400-1700 C and a pressure range of 10-40 Mpa for a period of 1-8 hours.

6. The method according to claim 1, wherein said step of sintering comprises a sintering procedure in a nitrogen-rich environment using a temperature range of 1,500-1,800 C using a pressure range of 10-40 Mpa for a period of 1-8 hours.

7. The method according to claim 1, wherein said step of heat treating comprises a heating process in an oxidative environment.

8. The method according to claim 1, wherein said heating process comprises a heating process in an oxidative environment using a temperature range of 1,000-1,400 C. for a period of time between 0.1 to 10 hours.

9. The method according to claim 1, wherein said step of creating said a hollow pathway comprises inserting a hollow tube through the center of said insulation material.

10. The method according to claim 1, wherein the step of pouring a predetermined amount of said conductive material comprises pouring said conductive material into a hollow tube.

11. The method according to claim 10, comprising the additional step of pulling out the hollow tube from said insulation material after pouring a predetermined amount of said conductive material on top of said insulation material and said conductive path to produce a compact.

12. A method for manufacturing an electrostatic chuck comprising the steps of:

a) providing a compact comprising an insulation material and an electrode formed adjacent said insulation material with a path of conductive material formed through said insulation material;

b) sintering said compact; and

c) heat treating said sintered compact in an oxygen-rich environment such that a uniform dielectric layer is formed along the electrode layer having no pores or microcracks.

13. A method for manufacturing an electrostatic chuck comprising the steps of:

a) providing a sintered compact comprising an electrode and a ceramic layer; and

b) heat treating the sintered compact in an oxygen-rich environment to produce a uniform dielectric layer along the electrode.

14. A method for controlling the thickness of a dielectric layer for an electrostatic chuck comprising the steps of:

a) providing a sintered compact comprising an electrode material having a predetermined particle size; and

b) heat treating the sintered compact in an oxygen-rich environment in order to produce a dielectric layer along said electrode material, wherein the thickness of said dielectric layer is directly related to the particle size of the electrode material.

15. The method according to claim 14, wherein the electrode material comprises titanium nitride.

16. The method according to claim 15, wherein the particle size of the titanium nitride is 6 um or larger.