Self-Aligned n-Channel Germanium MOSFETs With a Thin Ge Oxynitride Gate Dielectric and Tungsten Gate

In this letter, we report self-aligned n-channel germanium (Ge) MOSFETs with a thin Ge oxynitride gate dielectric and tungsten gate electrode. Excellent off-state current is achieved through the reduction of junction leakage. For the first time, we have demonstrated an n-channel Ge MOSFET with a subthreshold slope of 150 mV/dec and an on-off current ratio of /spl sim/10/sup 4/.