Patent attributes
An electrostatic chuck module for a semiconductor manufacturing apparatus which can be cooled with water and in which there is no penetration leak includes an electrostatic chuck plate of alumina and a cooling plate which is bonded to the electrostatic chuck, wherein the cooling plate is formed by forging processing to a Cu-based composite material comprising Cu—W, Cu—W—Ni, Cu—Mo, or Cu—Mo—Ni. By adjusting the ratio of Cu and Ni having a great thermal expansion coefficient and W and Mo having a small thermal expansion coefficient in a Cu-based composite material, it is possible to obtain a highly thermally conductive material having the same thermal expansion coefficient as an alumina material for an electrostatic chuck. However, since such a composite material has a penetration leak, it cannot be used in a vacuum system. According to the present invention, by conducting forging processing, a penetration leak can be prevented. Also, corrosion resistance which is important for a cooling plate can be improved by applying a Ni, Cr or Cu film by plating or sputtering.