Patent attributes
An electrostatic chuck capable of widening a temperature range and reducing a variation in thermal conductivity between the electrostatic chuck and the flat substrate over time is provided. The chuck includes: a body that has an internal electrode for attracting a flat substrate by an electrostatic force provided therein, a plurality of protrusions formed on one surface of the body serving as an electrostatic attraction surface, and projections provided on the top surfaces of some or all of the plurality of protrusions. In the electrostatic chuck, a region of the top surface of each of the minute projections on which the flat substrate is loaded is referred to as a mounting surface, and the total area of the mounting surfaces of the minute projections is equal to or larger than 0.01% and equal to or smaller than 2% of the area of the electrostatic attraction surface.