PURPOSE: To secure the adhesion strength and electrical connection at a lamination interface by completely eliminating the natural oxide film of two substrates with a silicon surface to be laminated, connecting fluorine to the surface, and then laminating two silicon substrates in this state and then performing heat treatment.
CONSTITUTION: An oxide film 2 and an amorphous silicon film 3 are formed on the surface of a single-crystal silicon substrate 1 and the single-crystal silicon substrate 1 and a single-crystal silicon substrate 4 are subjected to normal washing treatment and are immediately overlapped. Then, heat treatment is performed in a hydrogen atmosphere of 550-800°C, thus laminating the single- crystal silicon substrate 1 and the single-crystal silicon substrate 4 and hence laminating two lamination interfaces with a silicon surface by heat treatment and at the same time electrically connecting the interfaces and forming a sharp impurity profile.
OKURA OSAMU
SHIGENIWA MASAHIRO
