Composite material, wafer holding member and method for manufacturing the same

摘要

A composite material according to the present invention, is composed of SiC, SiO₂, at least one out of Al and Si, with He leak rate of 1.3x10^-10 Pa.m³/sec or below, thereby providing a composite material, which has a higher vacuum air-tightness, an excellent thermal conductivity, an adjustable coefficient of thermal expansion, small variation in strength and higher reliability, and a method for manufacturing the composite material, and a wafer holding member including the composite material.