High mobility high on/off ratio C-V dispersion-free Ge n-MOSFETs and their strain response

The record high peak mobility of ∼1050 cm2/V-s on (001) Ge substrate is demonstrated in NFET. High-quality Ge/GeO 2 interface is ensured by rapid thermal oxidation (RTO) and remote ozone plasma treatment. The best achieved subthreshold swing is 150mV/dec and the on/off ratio is 2×104. The low defective n+/p junction produced a record high on/off ratio of 2×105, an ideality factor of 1.05 and strong electroluminescence. For the first time, it is reported that the uniaxial tensile strain (0.08%) on channel direction gives the best mobility enhancement (12%) among the different strain configurations, consistent with theoretical calculation.