| 摘要 |
PURPOSE:To obtain the titled device in which elements are refined by a simple process, by a method wherein silica containing a required concentration of impurity is applied to the substrate and heat-treated. CONSTITUTION:A P-well 2 is formed in the N-type Si substrate 1, and an oxide film 3 for element isolation is grown; then, a gate oxide film 4 and a gate electrode poly Si 5 are grown. Next, the substrate surface 6 of the source and drain is exposed by etching the poly Si 5 and the gate oxide film 4, and silica 7 containing an N-type impurity at a concentration of 1X10<20>cm<-3> or more is applied. The silica 7 is selectively removed by excluding the NMOS region, and the whole is coated with a silica 8 containing a P-type impurity at a concentration of 1X10<20>cm<-3> or more. On irradiation with e.g. halogen lamp light and heat treatment at 900 deg.C or more for 90sec or less, the source-drain donor diffused layers 9 of the NMOSFET and its source-drain acceptor diffused layers 10 are formed out of the silicas 7 and 8. |
