Patent ID: 6537513
Filing Date: 2003-03-25
Classification: H01L

Abstract:
A substrate for fabricating semiconductor devices based on Group III-V semiconductors, said substrate comprising:a base substrate: a first buffer layer, said buffer layer comprising a Group III-V semiconducting material deposited on said base substrate at a temperature below that at which said Group III-V semiconducting material crystallizes, said Group III-V semiconducting material being crystallized by heating said buffer layer to a temperature above that at which said Group III-V semiconducting material crystallizes to form a single crystal after said Group III-V semiconducting material has been deposited; a first single crystal layer comprising a Group III-V semiconducting material deposited on said first buffer layer at a temperature above that at which said Group III-V semiconducting material crystallizes, said first single crystal layer having a thickness of at least 300 nm; a second buffer layer, said second buffer layer comprising a Group III-V semiconducting material deposited on said first single crystal layer at a temperature below that at which said Group III-V semiconducting material crystallizes, said Group III-V semiconducting material being crystallized by heating said buffer layer to a temperature above that at which said Group III-V semiconducting material crystallizes to form a single crystal after said Group III-V semiconducting material has been deposited; and a second single crystal layer comprising a Group III-V semiconducting material deposited on said second buffer layer at a temperature above that at which said Group III-V semiconducting material crystallizes.