Electrostatic chuck for holding wafer

Abstract

An electrostatic chuck for holding a wafer includes a ceramic plate of which one main surface is formed to work as a mounting surface for mounting the wafer, and electrostatic attraction electrodes formed on a lower surface of the ceramic plate or in the ceramic plate. A recess portion having a depth in a range of from 3 to 10 μm is formed on one main surface of the ceramic plate excluding an outer peripheral portion thereof. The waviness of a top face of the outer peripheral portion is set to 1 to 3 μm, a gas groove is provided to a peripheral portion of a bottom surface of the recess-portion bottom surface, and electrostatic attraction electrodes are disposed in the ceramic plate disposed below the bottom surface of the convex portion. In the electrostatic chuck thus constructed, a high wafer-dechucking sensitivity can be exhibited.

Dependencies are inferred from the claim text.