| 摘要 |
PURPOSE:To prevent abnormal diffusion by diffusing B from B2O3 in an atmospheric gas obtained by adding steam with specified steam pressure to dry Ar. CONSTITUTION:A quartz manufacturing tool 5 on which a semiconductor wafer 20, sections thereof except a surface 3 on which B is to be diffused are coated with an oxide film 4, and a diffusing source 10 formed by applying B2O3 2 on the surface of an Si wafer 1 are placed is arranged into a quartz tube 6, dry Ar gas is flowed from a gas inflow port 7 at the rate of 0.2-0.3l/min while a steam generator 8 is mounted to the gas inflow port 7 and the steam of 4.93mm.Hg(1 deg.C)-5.68mm. Hg(3 deg.C) is introduced as steam pressure from pure water 9. Thus, the abnormal diffusion of B is prevented, and the concentration of the surface can also be controlled. |
