Dielectric layer for electrostatic chuck and electrostatic chuck

• US 9,120,704 B2
• Filed: 10/15/2013
• Issued: 09/01/2015
• Est. Priority Date: 10/15/2012
• Status: Active Grant

• Current Assignee: Shinko Electric Industries Company Limited (Fujitsu Limited), Japan Fine Ceramics Center, Nippon Tungsten Co., Ltd., Trek Holding Co. Ltd. (Thermo Fisher Scientific Incorporated)
• Original Assignee: Shinko Electric Industries Company Limited (Fujitsu Limited), Japan Fine Ceramics Center, Nippon Tungsten Co., Ltd., Trek Holding Co. Ltd. (Thermo Fisher Scientific Incorporated)
• Inventors: Tsutsumi, Kouta, Nagano, Mitsuyoshi, Tamagawa, Koki, Shiraiwa, Norio, Yoshikawa, Tadayoshi, Saito, Miki, Uehara, Toshio, Matsubara, Hideaki, Matsuda, Tetsushi
• Primary Examiner(s): TURNER, ARCHENE A
• Application Number:
  US14/054,417
• Publication Number:
  US 20140103612A1
• Time in Patent Office: 686 Days
• Field of Search: 501/96.1, 501/127, 428/325, 428/697, 428/699, 428/701, 428/702, 361/234
• US Class Current: 1/1
• CPC Class Codes: C04B 2235/3232 Titanium oxides or titanates, e.g. rutile or anatase
• CPC Class Codes: C04B 2235/3843 Titanium carbides
• CPC Class Codes: C04B 2235/3856 Carbonitrides, e.g. titanium carbonitride, zirconium carbonitride
• CPC Class Codes: C04B 2235/3886 Refractory metal nitrides, e.g. vanadium nitride, tungsten nitride
• CPC Class Codes: C04B 2235/5445 submicron sized, i.e. from 0,1 to 1 micron
• CPC Class Codes: C04B 2235/77 Density
• CPC Class Codes: C04B 2235/786 Micrometer sized grains, i.e. from 1 to 100 micron
• CPC Class Codes: C04B 2235/96 Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
• CPC Class Codes: C04B 35/10 based on aluminium oxide
• CPC Class Codes: C04B 35/117 Composites
• CPC Class Codes: C04B 35/645 Pressure sintering
• CPC Class Codes: H01L 21/6831 using electrostatic chucks
• CPC Class Codes: H01L 21/6833 Details of electrostatic chucks
• CPC Class Codes: Y10T 279/23 with magnetic or electrostatic means

Abstract

A dielectric layer for an electrostatic chuck is formed of a ceramic material having a first phase including aluminum oxide and a second phase including composite carbonitride (Ti, Me)(C, N) that contains titanium as fine grains. The Me represents a transition element and metals of Group 4 to Group 6 such as Mo and W. The ceramic material that includes the second phase by 0.05 vol % to 2.5 vol % has a volume resistivity value of about 10⁸ to 10¹³ (Ω·cm) necessary for a Johnsen-Rahbek type electrostatic chuck.

Claims

1. A dielectric layer for an electrostatic chuck comprising:

a ceramic material that includes an aluminum oxide, wherein

in a first phase of the aluminum oxide, a second phase is dispersed;

the second phase comprises composite carbonitride of Ti and an Me expressed by (Ti, Me)(C, N);

wherein

the Me comprises one or more of transition elements of Group 3 to Group 11 of the periodic table;

a volume ratio of the second phase being in a range of 0.05% to 2.5% by volume.

2. The dielectric layer according to claim 1, wherein an average grain size of the composite carbonitride is in a range of 10 nm to 300 nm.

3. The dielectric layer according to claim 1, wherein the Me is one or more elements of Group 4 to Group 6 of the periodic table.

4. The dielectric layer according to claim 1, wherein the Me is Mo or at least two types of transition metals that includes Mo.

5. The dielectric layer according to claim 1, wherein the (Ti, Me)(C, N) is (Ti_1-xMe_x)(C_1-yN_y) where 0.02≦

x≦

0.3 and 0.1≦

y≦

0.7.

6. An electrostatic chuck comprising the dielectric layer according to claim 1.

7. An electrostatic chuck comprising the dielectric layer according to claim 2.

8. An electrostatic chuck comprising the dielectric layer according to claim 3.

9. An electrostatic chuck comprising the dielectric layer according to claim 4.

10. An electrostatic chuck comprising the dielectric layer according to claim 5.