MANUFACTURE OF SILICON SUBSTRATE

摘要

PURPOSE:To improve the hold time of an MOS memory IC by executing heat treatment at two stages of a high temperature and a low temperature to the specular Si substrate and removing a surface layer. CONSTITUTION:The P type Si substrate with a mirror surface is manufactured from a CZ non-dislocation single crystal containing the oxygen concentration of 14-18X10<17> atom/cc, treatment for 2hr at 1,150 deg.C and 8hr at 700 deg.C in Ar is executed to the substrate, and the surface layer is etched by approximately 0.5- 3mu. The hold time of the MOS memory is improved remarkably through the removal of the surface layer.