| 摘要 |
PURPOSE:To reduce a capacity between a source and a drain by forming a thick insulating film formed on a gate insulating film by a selective oxidation of a semiconductor layer to expand the semiconductor layer to obtain a thick insulating film, and then reducing a stepwise difference from a gate polycrystalline layer formed later. CONSTITUTION:An n<-> type layer 2 is grown on an n<+> type semiconductor sub strate 1, two p<+> type region 3 is grown on the prescribed region, and a p-type layer 4 is accumulated on the entire surface which includes the region 3. Then, a gate oxide film 5a is coated on the entire surface, a plurality of polycrystalline Si electrodes 6 are formed on the film 5a except the region 3, the surface is coated with an oxidation resistant insulating film 11, the layer 4 is selectively oxidized to alter the surface of the layer 4 between the electrodes 6 to thick oxide films 5d1, 5d2. Then, only the film 5d2 disposed on the region 3 is removed, a thin oxide film 5e is newly coated on the region 3, a shallow n<+> type source region 8 is formed on the outer periphery of the region 3 by ion implanting, and an n-type channel region 12b is simultaneously formed under the film 5d1 therebetween. |
