Solid-State Electronics, Vol.86, 45-50, 2013
Unexpected impact of germanium content in SiGe bulk PMOSFETs
In this paper, we investigate the impact of silicon-germanium channel on PMOSFETs with TiN metal and HfSiON dielectrics gate stack. Performance increase with Ge incorporation in the channel is higher than theoretically expected. Threshold voltage is outstandingly lowered and mobility is highly improved. Poisson-Schrodinger simulations are carried out to interpret the experimental results. Room as well as low temperature mobility measurements and low frequency noise analysis are performed in order to better understand this unforeseen germanium influence. Smaller Coulomb scattering rates are clearly evidenced in SiGe devices, probably explaining the higher mobility. (C) 2013 Elsevier Ltd. All rights reserved.