ARTIFICIAL SUBSTRATES FOR N-TYPE AND P-TYPE SIGE HETEROSTRUCTURE FIELD-EFFECT TRANSISTORS

The high carrier mobility in SiGe heterostructure layers enable an inc reased RF performance of field-effect transistors (FETs) compared with standard metal-oxide semiconductor (MOS) devices. Both p- and n-type transistors require relaxed SiGe buffer layers as artificial substrate s. In this paper, the influence of molecular beam epitaxy (MBE) growth parameters on the surface morphology and crystal quality of strain re lieved SiGe buffers on Si is discussed. The surface roughness of grade d and constant composition buffers grown under different conditions is related to electrical results. (C) 1998 Elsevier Science S.A. All rig hts reserved.