| 摘要 |
PROBLEM TO BE SOLVED: To improve workability of a yttrium oxide material, and further, to improve its wear resistance. SOLUTION: An electrostatic chuck 20 is composed of a yttrium oxide material in which, provided that fracture toughness is defined as K<SB>IC</SB>(MPa m<SP>1/2</SP>) and Vickers hardness in the weighting of 9.8 N is defined as Hv (GPa), Vickers hardness Hv is≥10 GPa, and K<SB>IC</SB>/Hv lies in the preferable range of≥0.15. Provided that the yttrium oxide is defined as a first phase as a base material, a second phase other than the first phase is preferably comprised by 5 to 20 vol.%. The second phase can be a compound showing a Vickers hardness Hv of≥12 GPa in the weighting of 9.8 N, e.g., a nitride or a carbide. Alternatively, the second phase can be an oxide in which a solid solution limit is present in≥5 mol% to yttrium oxide or a compound between the oxide and yttrium oxide, e.g., a rare earth oxide. COPYRIGHT: (C)2010,JPO&INPIT |
