High-performance double-layer epitaxial-channel PMOSFET compatible with a single gate CMOSFET

High-performance double-layer epitaxial-channel PMOSFET compatible with a single-gate CMOSFET have been demonstrated. The thin epitaxial-Si channel is composed of a lower highly boron-doped (1.2-2.4/spl times/10/sup 18/ cm/sup -3/) layer and an upper nondoped layer, and is applicable to NMOSFET. This PMOS achieves the highest g/sub m/ with acceptable short-channel effects among PMOSs having various types of channels. The minimum gate delay of CMOS is 15.9 ps at 2.5 V for a CMOS ring oscillator with 10 /spl mu/m gate width.