TWI780384B

Provided is an electrostatic chuck which comprises: a base plate; and a ceramic dielectric substrate installed on the base plate to have a first circumferential surface exposed to the outside. The first circumferential surface at least includes: a first area; and a second area adjacent to the first area. In the first area of the first circumferential surface, formed are a plurality of first grooves, and at least one first gas introduction hole connected to at least one of the plurality of first grooves. The plurality of first grooves include: a first border groove which is formed to be closest to a first border between the first area and the second area, and is extended along the first border; and at least one groove in the first area, which is different from the first border groove. In the second area of the first circumferential surface, formed are a plurality of second grooves and at least one second gas introduction hole connected to at least one of the plurality of second grooves. The plurality of second