Electrostatic chucks with flat film electrode

• US 20010043452A1
• Filed: 12/05/2000
• Published: 11/22/2001
• Est. Priority Date: 12/09/1999
• Status: Active Grant

• Current Assignee: Saint-Gobain Ceramics & Plastics Incorporated (Compagnie De Saint-Gobain)
• Original Assignee: Saint-Gobain Ceramics & Plastics Incorporated (Compagnie De Saint-Gobain)
• Inventors: Zandi, Morteza, Divakar, Ramesh
• Granted Patent: US 6,744,618 B2
• Time in Patent Office: Days
• US Class Current: 361/234
• CPC Class Codes: H01L 21/6833 Details of electrostatic chucks
• CPC Class Codes: H02N 13/00 Clutches or holding devices using electrostatic attraction, e.g. using Johnson-Rahbek effect
• CPC Class Codes: Y10T 279/23 with magnetic or electrostatic means

Abstract

An electrostatic chuck having an essentially flat film electrode which is essentially parallel to the chucking surface of the electrostatic chuck is fabricated by depositing a film electrode, preferably by screen printing, onto a surface of a sintered ceramic substrate. A green ceramic layer is formed or molded onto the film electrode and the resulting structure is sintered, thereby producing the electrostatic chuck.

Claims

1. An electrostatic chuck comprising:

a) a chuck body having a chucking surface;

b) a film electrode embedded in the chuck body; and

c) a dielectric layer having an essentially uniform thickness between the film electrode and the chucking surface.

2. The electrostatic chuck of

claim 1

wherein thickness of the dielectric layer has a variation expressed as a range which is smaller than about 700 microns.

3. The electrostatic chuck of

claim 1

wherein thickness of the dielectric layer has a variation expressed as a standard deviation which is less than about 160 microns.

4. The electrostatic chuck of

claim 1

wherein the dielectric layer has a thickness ranging from about 50 microns to about 5000 microns.

5. The electrostatic chuck of

claim 1

wherein the chuck body includes aluminum nitride.

6. The electrostatic chuck of

claim 1

wherein the film electrode includes a metal selected form the group consisting of molybdenum, tungsten and any combination thereof.

7. The electrostatic chuck of

claim 1

wherein the film electrode has a thickness ranging from about 50 microns to about 250 microns.

8. The electrostatic chuck of

claim 1

wherein the film electrode is a screen printed electrode.

12. The method of

claim 1

wherein the film electrode includes a first metal selected form the group consisting of molybdenum, tungsten and any combination thereof.

13. The method of

claim 12

wherein the film electrode further includes a second metal selected from the group consisting of nickel, cobalt and any combination thereof.

14. The method of

claim 13

wherein the second metal is essentially dissolved in the first metal.

9. A method of producing an electrostatic chuck comprising the steps of:

a) screen printing a film electrode onto a surface of a sintered substrate;

b) forming a green ceramic layer onto and overlaying the film electrode; and

c) sintering the green ceramic layer under pressure, thereby forming the electrostatic chuck.

10. The method of

claim 9

wherein the sintered substrate includes aluminum nitride.

11. The method of

claim 9

wherein the green ceramic layer includes aluminum nitride.

15. The method of

claim 9

wherein screen printing includes silk screening glass-free conductive pastes.

16. The method of

claim 9

wherein agglomerates are removed prior to forming the green ceramic layer.

17. The method of

claim 9

wherein the green ceramic layer is evenly distributed onto the film electrode.

18. The method of

claim 9

wherein hot pressing is in an inert atmosphere.

19. The method of

claim 9

further including heat treating in an atmosphere consisting essentially of argon.

20. An electrostatic chuck produced by a method comprising the steps of:

a) screen printing a film electrode onto a surface of a sintered substrate;

b) forming a green ceramic layer onto and overlaying the film electrode; and

c) sintering the green ceramic layer under pressure, thereby forming the electrostatic chuck.

21. A method of producing an electrostatic chuck comprising the steps of:

a) depositing a film electrode by a process selected from the group consisting of chemical vapor deposition and physical vapor deposition onto a surface of a sintered substrate;

b) forming a green ceramic layer onto and overlaying the film electrode; and

c) sintering the green ceramic layer under pressure, thereby forming the electrostatic chuck.

22. An electrostatic chuck produced by the method of

claim 21

.

23. A method of producing an electrostatic chuck comprising the steps of:

(a) screen printing a film electrode onto a surface of a sintered substrate, wherein the film electrode includes a first metal and a second metal, all the second metal being essentially dissolved in the first metal;

(b) forming a green ceramic layer onto and overlaying the film electrode; and

(c) sintering the green ceramic layer under pressure, thereby forming the electrostatic chuck.