METHOD FOR FABRICATING ANNEALED WAFER

摘要

PURPOSE: A method for fabricating an annealed wafer is provided to fabricate a high-quality annealed wafer by eliminating the boron ions absorbed to the surface of a silicon wafer without an additional process in a heat treatment process for removing a crystal defect of the silicon wafer. CONSTITUTION: The silicon wafer is preheated to a temperature of 500 deg.C in the furnace which is of an atmosphere of argon gas, nitrogen gas or inert gas. The gas atmosphere of the furnace is changed to a gas atmosphere of hundred percent hydrogen gas and the second heat treatment process is performed while the temperature of the furnace is increased to a predetermined temperature from 850 deg.C to 1150 deg.C, so that the boron ions absorbed to the surface of the silicon wafer is eliminated. The gas atmosphere of the furnace is changed to a gas atmosphere of hundred percent argon and the temperature of the furnace is increased to a temperature of 1200 deg.C. The third heat treatment process is performed for a time interval of one hour while the temperature is maintained. The temperature of the furnace is decreased to a temperature not greater than 500 deg.C or so.