r-PLANE SAPPHIRE SUBSTRATE FOR CRYSTAL BREEDING, AND CLEANING METHOD OF r-PLANE SAPPHIRE SUBSTRATE

摘要

PROBLEM TO BE SOLVED: To provide an r-plane sapphire substrate for crystal breeding having a deduced concentration of heavy metals (Ti, Fe, Ni, Cu, Zn) that cause a low yield in manufacturing a silicon crystal film for use in a semiconductor device, and to provide a cleaning method thereof.;SOLUTION: An r-plane sapphire substrate for crystal breeding of which an r plane is the plane direction of a principal plane of the substrate is used for breeding a crystal film of silicon or the like by an epitaxial growth method. The Fe concentration and Ni concentration in a substrate surface layer obtained by measuring the principal plane by total reflection X-ray fluorescence analysis (TXRF) are each 1×10¹⁰ atms/cm² or less. In a cleaning method of the r-plane sapphire substrate, the principal plane of the substrate is washed with a cleaning fluid containing hydrofluoric acid, and then washed again with a second cleaning fluid containing hydrochloric acid of 0.0001 or more normal concentration.;COPYRIGHT: (C)2016,JPO&INPIT