Provided is an electrostatic chuck, including: a first insulating layer including a heat conductive silicone rubber with a thermal conductivity of at least 0.2 W/mK, which is formed on top of a metal substrate, either directly or with an adhesive layer disposed therebetween; a conductive pattern, which is formed on top of the first insulating layer, either directly or with an adhesive layer disposed therebetween; a second insulating layer including an insulating polyimide film, which is formed on top of the conductive pattern, either directly or with an adhesive layer disposed therebetween; and a third insulating layer including a heat conductive silicone rubber with a thermal conductivity of at least 0.2 W/mK, a hardness of no more than 85, and a surface roughness of no more than 5 .mu.m, which is formed on top of the second insulating layer, either directly or with an adhesive layer disposed therebetween. Also provided is a process for holding a substrate on the electrostatic chuck. The electrostatic chuck exhibits excellent cooling performance and insulation performance, and is ideal for holding a substrate during the production of a semiconductor integrated circuit.