| 摘要 |
<p>PURPOSE:To reduce a device area, increase the degree of integration and obtain a thin film transistor easily with a smaller number of production processes by setting a portion which faces a lower part gate electrode of a lower part gate insulation film to a memory region, forming an upper part electrode so that it may face the whole body of a semiconductor layer, and increasing the thickness of an upper part gate insulation film on a part corresponding to the memory region of the semiconductor layer. CONSTITUTION:A lower part gate electrode G10 is formed on the opposite side of a central part of a semiconductor layer 13 in its channel longitudinal direction and sets only central part of a lower part gate insulation film 12 which faces the lower part gate electrode G10 to a memory region. On the other hand, an upper part gate electrode G20 is designed as an electrode which faces the whole body of the semiconductor layer 13. The thickness of an upper gate insulation film 15 located between the upper part gate electrode G20 and the semiconductor layer 13 is increased in an upper part of the memory region of the lower part gate insulation film 12 and an outward part from the position which nearly faces the central part of a source electrode S and a drain electrode D.</p> |
