Ge Complementary Tunneling Field-Effect Transistors Featuring Dopant Segregated NiGe Source/Drain

Ge complementary tunneling field-effect transistors (TFETs) are fabricated with the NiGe metal source/drain (S/D) structure. The dopant segregation method is employed to form the NiGe/Ge tunneling junctions of sufficiently high Schottky barrier heights. As a result, the Ge p- and n-TFETs exhibit decent electrical properties of large ON-state current and steep sub-threshold slope (S factor). Especially, I_\rm d of 0.2 \muA/μm is revealed at V_\rm g-V_\rm th=V_\rm d=\pm 0.5 V for Ge pTFETs, with the S factor of 28 mV/dec at 7 K.