| 摘要 |
PURPOSE:To shorten a channel easily by forming a semiconductor region having the same conduction type as a substrate or a well and concentration higher than the substrate or the well to the lower section of source-drain semiconductor regions in low concentration and a channel region. CONSTITUTION:With a substrate 1, an element active region is regulated by a field insulating film 2 consisting of thick SiO2, and a gate insulating film 4 composed of SiO2 is shaped in the element active region. A gate electrode 5 is formed onto the gate insulating film 4, and As ions are implanted to a second semiconductor region 3 in the side sections of the gate electrode 5 to shape N type low-concentration third semiconductor regions 6. A side wall 7 is formed to the side section of the gate electrode 5 through etching, an insulating film 8 is shaped through thermal oxidation, and phosphorus (P) ions are implanted to form second conduction type high-concentration fourth semiconductor regions to the side sections of the side wall. There is the high-concentration (P<+>) second semiconductor region 3 in the lower sections of the third semiconductor regions 6 and a channel region in the lower section of the gate insulating film 4. The second semiconductor region 3 extends over the whole channel region, thus improving the effect of the shortening of a channel. |
