摘要 |
PURPOSE:To finish the surface of an InP substrate to a mirror face free from scratches, flaws and strains, by polishing the InP substrate with a mixture of an aqueus solution of colloidal silica and a proper amount of a soluton obtainined by dissolving bromine in methyl alcohol. CONSTITUTION:An InP substrate is polished with a polyurethane-polyester double-layered nonwoven cloth, etc. by a rotary disc polisher using a liquid mixture containing 0.16-0.40vol% bromine and obtained by mixing a methyl alcohol solution of bromine with an aqueous solution of 1-5wt% colloidal silica. The surface of an InP useful as a substrate of a semiconductor device, etc. can be polished easily to a mirror surface having a surface roughness of <= about 20Angstrom without causing the polishing strain by the combined action of the chemical and the mechanical polishing actions not only at the (100) face of the InP but also at the (111) face thereof. The polishing agent used in the process is available at a low cost, and a moderate rate of polishing can be attained. |