Electrostatic chuck and manufacturing method for the same, and alumina sintered member and manufacturing method for the same

• US 7,416,793 B2
• Filed: 12/23/2004
• Issued: 08/26/2008
• Est. Priority Date: 12/26/2003
• Status: Active Grant

• Current Assignee: NGK Insulators Limited
• Original Assignee: NGK Insulators Limited
• Inventors: Nobori, Kazuhiro, Kawajiri, Tetsuya, Matsuda, Hiroto, Imai, Yasuyoshi
• Primary Examiner(s): Zimmerman; John J.
• Assistant Examiner(s): Austin; Aaron
• Application Number:
  US11/021,742
• Publication Number:
  US 20050152089A1
• Time in Patent Office: 1,342 Days
• Field of Search: 219/444.1, 279/128, 361/234, 428/701, 428/702, 501/127, 501/153
• US Class Current: 428/701
• 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 comprises a dielectric ceramic layer made of an alumina sintered body having a volume resistivity equal to or greater than about 1×10¹⁷Ω·cm at room temperature and a volume resistivity equal to or greater than about 1×10¹⁴Ω·cm at 300° C., and an electrode formed on one surface of the dielectric ceramic layer.

Claims

1. An electrostatic chuck, comprising:

a dielectric ceramic layer made of an alumina sintered body having a volume resistivity equal to or greater than about 1×

10¹⁷Ω

·

cm at room temperature and a volume resistivity equal to or greater than about 1×

10¹⁴Ω

·

cm at 300°

C.; and

an electrode formed on one surface of the dielectric ceramic layer.

2. The electrostatic chuck, according to claim 1, wherein the alumina sintered body has a volume resistivity equal to or greater than about 1×

10¹⁴Ω

·

cm at 400°

C.

3. The electrostatic chuck, according to claim 1, wherein the alumina sintered body has a purity equal to or greater than about 99.5% by weight, and a density in a range from about 3.80 to about 4.00 g/cm³.

4. The electrostatic chuck, according to claim 1, wherein the alumina sintered body is sintered in an inert atmosphere or a reduction atmosphere by hot press method.

5. The electrostatic chuck, according to claim 1, wherein the dielectric ceramic layer has a thickness in a range from about 0.05 mm to about 0.50 mm.

6. The electrostatic chuck, according to claim 1, further comprising:

a ceramic substrate joined to the dielectric ceramic layer via the electrode;

wherein the dielectric ceramic layer, the electrode, and the ceramic substrate are an integrated body by hot press method.

7. The electrostatic chuck, according to claim 6, wherein the ceramic substrate is an alumina sintered body.

8. An electrostatic chuck, comprising:

a dielectric ceramic layer made of an alumina sintered body having a volume resistivity equal to or greater than about 1×

10¹⁷Ω

·

cm at room temperature and a volume resistivity equal to or greater than about 1×

10¹⁵Ω

·

cm at 200°

C.; and

an electrode formed on one surface of the dielectric ceramic layer.

9. The electrostatic chuck, according to claim 8, wherein the alumina sintered body has a purity equal to or greater than about 99.5% by weight, and a density in a range from about 3.80 to about 4.00 g/cm³.

10. The electrostatic chuck, according to claim 8, wherein the alumina sintered body is sintered in an inert atmosphere or a reduction atmosphere by hot press method.

11. The electrostatic chuck, according to claim 8, wherein the dielectric ceramic layer has a thickness in a range from about 0.05 mm to about 0.50 mm.

12. The electrostatic chuck, according to claim 8, further comprising:

a ceramic substrate joined to the dielectric ceramic layer via the electrode;

wherein the dielectric ceramic layer, the electrode, and the ceramic substrate are an integrated body by hot press method.

13. The electrostatic chuck, according to claim 12, wherein the ceramic substrate is an alumina sintered body.

14. The electrostatic chuck according to claim 8, wherein the dielectric ceramic layer consists essentially of alumina.

15. The electrostatic chuck according to claim 8, wherein the alumina sintered body of the dielectric ceramic layer is a twice-sintered alumina body.

16. The electrostatic chuck according to claim 15, wherein the alumina sintered body of the dielectric ceramic layer is sintered by a hot press method at least as a second sintering step to form the twice-sintered alumina body.

17. An alumina sintered member having a volume resistivity equal to or greater than about 1×

10¹⁷Ω

·

cm at room temperature and a volume resistivity equal to or greater than about 1×

10¹⁴Ω

·

cm at 300°

C.

18. The alumina sintered member, according to claim 17, wherein the alumina sintered member has a volume resistivity equal to or greater than about 1×

10¹⁴Ω

·

cm at 400°

C.

19. The alumina sintered member, according to claim 17, wherein the alumina sintered member has a purity equal to or greater than about 99.5% by weight, and a density in a range from about 3.80 to about 4.00 g/cm³.

20. The alumina sintered member, according to claim 17, wherein the alumina sintered member is sintered in an inert atmosphere or a reduction atmosphere by hot press method.

21. A manufacturing method for an alumina sintered member, comprising:

forming an alumina sintered member having a volume resistivity equal to or greater than about 1×

10¹⁷Ω

·

cm at room temperature and a volume resistivity equal to or greater than about 1×

10¹⁴Ω

·

cm at 300°

C. by sintering with ceramic raw material powder including at least about 99.5% by weight alumina in an inert atmosphere or a reduction atmosphere by hot press method.

22. A manufacturing method for an alumina sintered member, comprising:

forming an alumina sintered member having a volume resistivity equal to or greater than about 1×

10¹⁷Ω

·

cm at room temperature and a volume resistivity equal to or greater than about 1×

10¹⁵Ω

·

cm at 200°

C. by sintering with ceramic raw material powder including at least about 99.5% by weight alumina in an inert atmosphere or a reduction atmosphere by hot press method.