| 摘要 |
PROBLEM TO BE SOLVED: To suppress variations in a threshold caused by a thickness of a silicon layer film of a complete depletion type SOI MOSFET. SOLUTION: A method for manufacturing a semiconductor device comprises the steps of implanting silicon ion in an embedded oxide film 2 through a silicon layer 3 of an SOI structure having the film 2 and the layer 3 sequentially provided on a silicon substrate 1, forming a fixed oxide film charge layer 4 at a silicon ion arrival distance, and providing a gate electrode on the layer 3 via a gate oxide film 5. Since the charge layer 4 has a function of reducing the threshold of the SOI MOSFET, the more the thickness of the silicon layer film is increased, the SOI MOSFET in which an effect of the variations of the thickness of the layer 3 to the threshold voltage is small, is obtained.
|
