SILICON SEMICONDUCTOR SUBSTRATE AND ITS MANUFACTURING METHOD

摘要

A method for manufacturing a silicon semiconductor substrate for semiconductor integrated circuit devices exhibiting a higher carrier mobility of the (110) surface, particularly a higher mobility of electrons that are carriers of an n-type FET. The surface is planarized on the order of atom size by a conventional RCA cleaning without carrying out any special cleaning and without carrying out radial oxidation, and resultantly the surface roughness is reduced. The major surfaces of the substrate are (110) surfaces or inclined (110) surfaces. Steps with magnitudes on the order of atom size are formed on the surface of the substrate generally along the <110> direction.