Patent attributes
Manufacturing a semiconductor device by removing the insulation film in an alignment mark-forming region, depositing a first semiconductor layer, removing the insulation film on the semiconductor substrate after the second semiconductor layer is formed, forming a first exposing region for exposing the semiconductor substrate through the second semiconductor layer and the first semiconductor layer with reference to the second semiconductor layer in the alignment mark-forming region as a first alignment mark for positioning, while forming, on the semiconductor substrate, a second alignment mark, forming a second exposing region for exposing the first semiconductor layer by using the second alignment mark as a reference for positioning, forming a cavity and forming a buried insulation layer in the cavity, and forming a first grate electrode by using the second alignment mark as a reference for positioning.