| 摘要 |
PURPOSE:To provide a high-quality wafer not containing crystal defects, by mixing oxygen gas into hydrogen gas before epitaxial-growing of silicon, and by pre-baking the wafer at the approximately same temperature as the normal epitaxial growing temperature. CONSTITUTION:After wafers are washed by the same method as prior arts, the wafers are heated A' for 20min at about 900 deg.C in atmosphere in which oxygen of 10ppm is mixed into hydrogen of 1atm, removing foreign matters mainly consisting of carbon. Next, into the reaction tube of an epitaxial apparatus, SiHCl3 gas as well as hydrogen gas being carrier gas is flowed, regulating the pressure in the reaction chamber to about 1Torr. Next, the wafers are heated to a temperature of about 900 deg.C to do epitaxial growth C; for a given time. |
