| 摘要 |
PURPOSE:To enable to form semiconductor regions of a prescribed conductive type, which are shallow and have a high surface impurity concentration, in substrates with a favorable reproducibility by a method wherein a glow discharge is performed in an atmosphere involving desired doped impurities. CONSTITUTION:The air in the interior of a reaction tank 1 is exhausted by a vacuum exhausting system 4 and after the reaction tank 1 has been brought in a high vacuum state of about 1X10<-7>Torr, a vacuum valve 8 is throttled and the exhausting speed of the vacuum exhausting system 4 is reduced, and at the same time, impurity gas is introduced through an adjusting circuit 6 and the pressure in the vacuum container 1 is adjusted to 0.1-10Torr. After that, when a glow discharge is made to perform between electrodes 2a and 2b, semiconductor regions involving the impurities are formed in semiconductor substrate 3 arranged on the electrode 2a heated to an arbitrary temperature, for example, to 300 deg.C. In particular, semiconductor regions of a high concentration of 10<21>-10<22>atom/cm<3> in surface concentration and formed with an extremely thin diffusion layer of about 500-1,500Angstrom thereon, which are impossible by a heat diffusion method and an ion-implantation method, can be formed. According to this method, there is no need to use a high-priced ion-implantation device and diffusion furnace. The semiconductor substrate placed in the interior of the vacuum container 1 are held at prescribed tempratures of 400 deg.C or less. |
