Patent attributes
According to one embodiment, an electrostatic chuck includes a ceramic dielectric substrate, a base plate, and a first porous part. The ceramic dielectric substrate has a first major surface and a second major surface. The base plate supports the ceramic dielectric substrate and includes a gas feed channel. The first porous part is provided between the base plate and the first major surface. The ceramic dielectric substrate includes a first hole part. The first porous part includes a porous section, and a first compact section being more compact than the porous section. As projected on a plane perpendicular to a first direction from the base plate to the ceramic dielectric substrate, the first compact section is configured to overlap the first hole part, and the porous section is configured not to overlap the first hole part.