| 摘要 |
PURPOSE:To establish a short channel structure and a high speed of operation by a method wherein a phosphorous and boron exist together in a gate electrode portion and a shallow diffusion layer is formed onto a multicrystal silicon layer on other sections while preventing a break-through of the boron. CONSTITUTION:A gate oxide film 13 is grown on a N type silicon substrate 11 and a multicrystal silicon film 14 is grown thereon. Subsequently, a thermal diffusion for the phosphorous is achieved by using an oxide film 15 for a mask to form a gate electrode 16, thereafter the oxide film 15 is removed and the boron is diffused over the entire region of the multicrystal silicon film 14 through a thermal diffusion. Subsequently, a thick oxide film is grown on the surface of the gate electrode 16 by providing a thermal oxidation for the multicrystal silicon, and a thin oxide film is grown on the surface of other regions, the boron is broken through from the multicrystal silicon film 14 wherein only the boron exists through the gate oxide film 13 and consequently a shallow diffusion layer 19 is formed. Subsequently, the multicrystal silicon film 14 on the other regions is removed while leaving the oxide film on the gate electrode 16. |
