SILICON OXYNITRIDE SINTERED COMPACT, A METHOD FOR PRODUCING THE SAME, MEMBER FOR TREATING SUBSTRATE, AND SEMICONDUCTOR WAFER HOLDER

摘要

PROBLEM TO BE SOLVED: To provide sintered silicon oxynitride that satisfactorily attain lightening and low thermal expansion without adverse effect of the dust and adsorbed gas in the pores on the process. SOLUTION: The objective sintered silicon oxynitride comprises the main constitution phase selected from silicon oxynitride, a mixture of silicon oxynitride with silicon dioxide and silicon nitride and the subconstitution phase of a rare-earth metal oxide and has a pore number of <=10/mm2 on the mirror- polished surface.