Enhanced Mobility in 100 nm Strained SiGe Vertical P-MOSFETs Fabricated by UHVCVD

Abstract

AbstractStrained SiGe vertical PMOSFETs with a channel length of 100 nm have been fabricated without sophisticated lithography and the whole process is compatible with a regular CMOS process. The source, channel and drain layers with in situ doping were grown by ultrahigh vacuum chemical vapor deposition (UHVCVD) at 500 °C. Atomic force microscopy (AFM) of the SiGe and silicon sample surfaces shows the RMS roughness to be 0.18 nm. X-ray diffraction (XRD) rocking curves of the Si (004) plane demonstrate that the SiGe layers do result in compressive strain. The drive current for the vertical SiGe PMOSFET was enhanced by as much as 80% as compared with the silicon control device, in both the forward and reverse modes of operation.