| 摘要 |
PURPOSE:To obtain effectively sufficiently large channel length by forming a high specific resistance layer of a silicon substrate formed by laminating two semiconductor layers of different specific resistance in a projected shape, and forming a channel region over the top and a side wall. CONSTITUTION:A thin film pattern of the first gate oxide film 11, a gate electrode forming metal film 12 and the first Si3N4 film 13 is formed on a high specific resistance semiconductor layer 10b. The second Si3N4 film 15 is formed on the side wall of this thin film pattern, and the high specific resistance semiconductor layer is removed except under the thin film pattern. An SiO2 film 16 is formed on the exposed portion of the semiconductor layer, an impurity is implanted to a low specific resistance semiconductor layer 10a to form a high density impurity region, the film 16 is removed, thermally oxidized to form oxide films 17, 20, a source region 18 and a drain region 19 are formed in the high density impurity region, and a gate electrode 22 is formed. |
