| 摘要 |
PROBLEM TO BE SOLVED: To provide a bipolar electrostatic chuck that can evenly fix a wafer onto an absorbing surface. SOLUTION: An electrostatic chuck 1 includes, on a ceramic substrate 2, a ceramic dielectric layer 6 that has an absorbing surface 3 made from a non-retaining material W, a first absorption electrode 4a on which positive voltage is applied, and a second absorption electrode 4b on which negative voltage is applied. The ceramic dielectric layer 6 is made from aluminum nitride with purity equal to 98% by weight or more. The main component of the absorption electrodes 4a and 4b is Mo, W, Ti, an alloy thereof, or at least one kind of sintered compact among TiN, WC, and TiC. A thickness Tb of the ceramic dielectric layer 6 between the adsorbing surface 3 and the second absorption electrode 4b is thicker than a thickness Ta of the ceramic dielectric layer 6 between the absorbing surface 3 and the first absorption electrode 4a. COPYRIGHT: (C)2007,JPO&INPIT |
