In this paper, we report Ge p-and n-channel metal-oxide-semiconductor field-effect transistors (MOSFETs) with NiGe source/drain (S/D) with high performance and low leakage current. The forward/reverse current ratio of the NiGe/n-Ge and NiGe/p-Ge junctions were ∼ 105 and ∼2 × 104 at |V| = 1V, respectively. Interface state densities D it of Al2O3/GeO2/Ge stack is improved to be around 1012/eV-1 cm2 near the midgap after forming gas annealing; the gate-stack also shows excellent reliability under constant field stressing. Both p-and n-channel MOSFETs show sufficiently high ION/IOFF ratio. High driving current of ∼9 and ∼ 4~μ A\μm at (|VGS}-VT = 0.8) V and (|VDS| = V is obtained, respectively, for p-and n-MOSFETs. Moreover, S/D series resistance (RSD) of the p-and n-MOSFET is reduced by ∼25 % and ∼42% as compared with that of the transistors with conventional p/n junctions.