Patent ID: 7436035

Claim:
A microelectronic structure, comprising: a silicon substrate having a top surface and a first conductivity type; a dielectric disposed superjacent the tip surface of the substrate; a gate electrode disposed superjacent the dielectric, the gate electrode having side wall spacers disposed along opposing vertical walls thereof; and a source terminal and a drain terminal, formed of a first single crystal epitaxial SiGe film and a second single crystal epitaxial SiGe film, wherein the first single crystal epitaxial SiGe film is of said first conductivity type and is formed below the top surface of said silicon substrate and partially underlies the gate electrode and the second single crystal epitaxial SiGe film is formed over the first single crystal epitaxial SiGe film and is of a second conductivity type and partially underlies the gate electrode, wherein the first single crystal epitaxial SiGe film and the second single crystal epitaxial SiGe film are substantially free of counterdopants.