| 摘要 |
PURPOSE:To obtain an ion implantation mask for self-alignment with high accuracy without damaging a gate oxide film by selectively applying a metallic thin-film on a poly Si gate electrode. CONSTITUTION:An element isolation region 1 is formed on a P type Si single crystal substrate 15, a gate oxide film 2 and a poly Si gate electrode 3 are shaped in the element region, and the ions of an N type impurity are implanted onto the substrate 1 in low concentration. A W thin-film 6 is grown selectively on the electrode 3. The N type impurity ions are implanted while using the electrode 3 and the film 6 as masks. A W silicide layer 8 is shaped on the electrode 3 through heat treatment, and a low-concentration junction layer 9 and a high- concentration junction layer 10 are obtained. According to said method, an ion implantation mask for self-alignment can be acquired with high accuracy without damaging the gate oxide film 2. The film 6 functions as a metal of a kind silicifying the electrode 3, thus reducing the number of the whole processes. |
