| 摘要 |
PROBLEM TO BE SOLVED: To provide an electrostatic chuck that exhibits excellent temperature uniformity even when it attracts a highly rigid object such as a sapphire substrate. SOLUTION: An electrostatic chuck is used to attract an object having a Young's modulus of 300 GPa or more. The rigidity ratio between a dielectric of the electrostatic chuck and the object to be attracted (obtained by dividing Young's modulus of the object to be attracted by that of the dielectric) is 1.0 or more. A surface of the dielectric has a ring-like ridge portion. The ratio D/Dd of the ring-like ridge portion's diameter D divided by the dielectric's diameter Dd is 0.75 or more. The attracting surface extending from the ring-like ridge portion to the center portion has a concave shape. The ratio H/D of the center portion's depth H divided by the ring-like ridge portion's diameter D is 2×10<SP>-5</SP>or less. COPYRIGHT: (C)2008,JPO&INPIT |
