| 摘要 |
PROBLEM TO BE SOLVED: To provide an SOI type semiconductor device and a method for forming it. SOLUTION: The SOI-type semiconductor device is formed on an SOI-type substrate comprising lower silicon, embedded oxidation, and SOI layers, and has an element region that is isolated by an element isolation film and the embedded oxidation layer and at the same time, forms the source/drain region for forming a MOS-type field effect transistor in a body comprising the SOI layer; and a ground region that is isolated from the element region by the element isolated film and is composed of the body comprising the SOI layer doped with impurities. At a connecting section which is one portion of a region, where the element separation film is formed between the ground and element regions, the bottom surface of an element isolation film is separated from the buried oxidation layer for electrically connecting the body in the element region to the body in the ground region via the SOI layer; and a silicon germanium layer is provided at the lower section of the SOI layer for allowing one portion of the silicon germanium layer, to exist in the SOI layer for connecting the body of the element region to the body of the ground region at the connecting section. |
