| 摘要 |
PURPOSE:To equip a silicon wafer with appropriate charactristics by a method wherein an oxide film is formed on the surface of a silicon wafer, the silicon wafer is subjected to heat treatment that is accomplished at a temperature not lower than 800 deg.C in an atmosphere containing hydrogen, for the effective elimination in a short period of time of oxygen precipitates out of the silicon wafer surface containing inter-lattice oxygen. CONSTITUTION:An Si wafer 11 is placed in a dry oxygen atmosphere with the oxygen diluted to 10% by dry argon for the formation of an oxide film 12 on the wafer surface. The Si wafer 11 is then heat-treated in an argon atmosphere containing 10% of hydrogen for the elimination of oxygen precipitates for the vicinity 1a of the wafer surface. A process follows wherein the oxide film 12 is removed by etching. In this process, oxygen in the vicinity 11a of the surface of the Si wafer 11 is diffused outward from the surface for the formation of a defect-free layer in the vicinity 11a of the wafer surface. Simultaneously, a layer containing few lattices is formed in the inside 11b of the wafer 11. A process follows wherein the wafer 11 is subjected to oxidation in a dry atmosphere at a temperature not lower than 800 deg.C, preferably at 1,000 deg.C, for the formation of an oxide film 13. A polycrystalline silicon film 14 is then formed containing phosphorus. |
