Patent ID: 8133815
Filing Date: 2012-03-13
Classification: B24B,H01L,Y10T

Abstract:
1. A compound-semiconductor-substrate polishing method comprising: a preparation step of preparing a gallium arsenide substrate; a pretreatment step of polishing at least a front side of the gallium arsenide substrate with a solution mixture of colloidal silica and a chlorine-based polishing solution; a first polishing step, subsequent to the pretreatment step, of carrying out on at least the front side of the gallium arsenide substrate a polishing utilizing a chloric polishing agent; and a second polishing step, subsequent to the first polishing step, of stopping supply of the chloric polishing agent and carrying out on the at least the front side of the gallium arsenide substrate a polishing operation utilizing an oxidant-free alkaline aqueous solution containing an inorganic builder and having a pH of 8.5 to 13.0 inclusive.