Semiconductor device with thin film silicon on insulator MOSFET

摘要

The semiconductor device includes a substrate (1b) with a main surface in which is formed a buried insulation layer (2) in a position separate from the main surface. Also provided is a LOCOS insulating film (3b), a thin film transistor, and an impurity layer (15). The LOCOS film is provided in the main surface of the semiconductor substrate to insulate one active region from another active region. The thin-layer transistor is formed in the active region and it has a gate electrode (8) on one active region with an intermediate gate insulating layer (7). Also provided is a pair of source/drain layers (5) in the substrate main surface on both sides of the gate electrode, and a channel region (4). The impurity layer is formed in the substrate with a high concentration impurity and it is directly under the buried layer. Pref. the thin-layer transistor is of planar or mesa type.