| 摘要 |
PURPOSE:To prevent a phenomenon of discharge around a semiconductor element and thereby to enable the attainment of high performance and high reliability, by providing a low-resistance semiconductor film with impurities of high concentration added thereto, and a high-resistance semiconductor film formed on an insulating film integrally with said semiconductor film and containing no impurities substantially. CONSTITUTION:An epitaxial layer 22 and first and second semiconductor layers 23a and 23b are formed on a substrate 21, and a field oxide film 25b, a gate oxide film 25c, a polycrystalline silicon film 26a, a photoresist film 27, a polycrystalline silicon film 26c and a semiconductor layer 28 are formed on the main surface of the epitaxial layer 22. Thereafter a silicon oxide film 25d containing no impurities is deposited and a PSG film 25e containing phosphorus of high concentration is formed. Next, contact holes are opened in the CVD-SiO2 film 25d and the PSG film 25e, a source Al electrode 29 and a gate Al electrode are formed therein, and thus DSA MOS FET having a field plate and a high- resistance polycrystalline silicon film 26a of non-dope together with a gate electrode film is completed. By this method, the attainment of high reliability and high performance is enabled. |
