Patent ID: 7205190

Claim:
A method of making a semiconductor device comprising: providing a layered substrate comprising a first semiconductor layer which forms a support substrate, an insulating layer provided on the first semiconductor layer, and a second semiconductor layer provided on the insulating layer; defining the layered substrate to have an element formation region, and an element isolation region that surrounds the element formation region; forming a mask on the second semiconductor layer to cover the element formation region, with the element isolation region remaining exposed; using the mask, etching the second semiconductor layer and the insulating layer in the element isolation region, to expose the support substrate in element isolation region, and to form a layered structure in the element formation region that includes a remaining insulating layer and a remaining second semiconductor layer; implanting ions to form a substrate contact region in the exposed support substrate in the element isolation region, while using the mask to prevent the ions from being implanted in the element formation region; after said implanting, forming an element isolation insulating layer directly on the exposed support substrate so as to surround the layered structure; removing the mask; after removing the mask, forming a gate oxide film and a gate electrode on the remaining second semiconductor layer; forming a drain region and a source region in the remaining second semiconductor layer by performing ion implantation with the gate electrode serving as a mask; annealing to simultaneously activate the substrate contact region, the drain region and the source region; and forming a metal layer with a high melting point on the drain and source regions and then siliciding the metal layer by performing heat treatment.