SEMICONDUCTOR SUBSTRATE AND METHOD FOR MANUFACTURING THE SAME FIELD-EFFECT TRANSISTOR AND METHOD FOR MANUFACTURING THE SAME

摘要

PROBLEM TO BE SOLVED: To obtain a semiconductor substrate having an SiGe layer of high planarization in a method for manufacturing a semiconductor substrate and a method for manufacturing a field-effect transistor, and to provide a semiconductor substrate and a field-effect transistor. SOLUTION: The semiconductor substrate is provided with an Si substrate 1 and SiGe layers 2, 3 formed on the Si substrate 1. The methods comprise a process for polishing the surface of the SiGe layer 3 by using polishing liquid which comprises colloidal silica having an average particle size of from 40 to 50 nm and pH value of from 10.0 to 11.0.