| 摘要 |
PURPOSE:To obtain the FET wherein currents are not saturated, by providing a semiconductor layer having a same conductive-type high-concentration layer and a reverse conductive-type high-concentration layer on both sides of a channel region on an insulating substrate, and providing a gate electrode on the channel region via an insulating film. CONSTITUTION:The insulating film 11 is provided on the surface of a semiconductor substrate 10, and the semiconductor layer comprising, e.g., an N<+> high concentration layer 13, an N type channel layer 12, and a P<+> high concentration layer 14 are formed. A shalow N<+> layer which prevents the depletion is formed in a part of the channel layer 12. The gate electrode 16 is provided on the top of the channel layer 12 via the insulating film 9'. A source electrode 8 and a drain electrode 9 are provided on each high concentration layers. The operating condition is set so that VD-VS>0, where VS is a substrate potential. In this FET, since the conductive channel spread from the boundary with the insulating film 11 when VG is increased, and the current component is caused by the alternating injections of electrons and holes in a junction region, the current is not saturated with respect to VD. Therefore the FET having a high current gain can be obtained. |
