Patent ID: 7507642

Claim:
A vapor-phase growth method in which a semiconductor layer is deposited on an active region as an epitaxial layer and is deposited on a separation silicon oxide layer as a polycrystalline layer in a vapor-phase growth process in which a silicon-germanium mixed crystal layer is deposited on a semiconductor substrate of a single crystal silicon substrate across said active region exposed to said single crystal silicon substrate surface and said separation silicon oxide layer for separating said active region, said vapor-phase growth method comprising the steps of: a first step of introducing silicon raw material gas and germanium raw material gas into a reaction furnace to thereby form a first semiconductor layer of a silicon-germanium mixed crystal film on said single crystal substrate surface; a second step of introducing silicon raw material gas and germanium raw material gas into said reaction furnace to thereby form a second semiconductor layer of a silicon-germanium mixed crystal layer; and a third step of introducing silicon raw material gas into said reaction furnace to thereby form a third semiconductor layer of a silicon layer, wherein, a laminated semiconductor layer structure formed by said first, second and third steps is deposited on a portion formed on an active region exposed to said single crystal silicon substrate surface as a single crystal semiconductor layer and is deposited on a portion formed on said separation silicon oxide layer as a polycrystalline semiconductor layer.