| 摘要 |
PURPOSE:To realize the extremely thin active layer having the high activation rate and mobility, a deep level, and a low concentration by implanting arsenic ions after covering the surface of a semiconductor substrate with a silicon nitride film (SiNx) in which a composition ratio of nitrogen and silicon is specified during the process of ion implantation of N-type impurity. CONSTITUTION:An SiNx film 2 of 50nm thick having an N composition of 2/3 is spread over a semi-insulating GaAs substrate 1 and further a CVD SiO2 film 3 is deposited on that to 200nm. Only the SiO2 film 3 of the region for forming a device is removed selectively, after which As ions 10 is implanted into the overall surface to 1.2X10<13>cm<-2> by 40 keV. Consequently the Si atoms only in the device forming region are recoil-implanted to form an active layer 4. Then it is possible to realize the thickness of an active layer of 30nm which is extremely thin. |
