High-k gate stack formation on strained SiGe substrate for MOSFET applications

In this paper, we examine the high-k gate stack formation on strained SiGe for p-channel MOSFET applications by comparing two different surface passivations. Experimental results show that although both surface nitridation and silicon passivation provide good MOS capacitors on SiGe substrates, the devices with ultra-thin Si passivation layer provides higher hole mobility than those with surface nitridation. It is believed that nitrogen incorporation during surface nitridation may degrade hole mobility. © The Electrochemical Society.