InGaAs and Ge MOSFETs with a common high κ gate dielectric

Ultra-high-vacuum (UHV) deposited Ga
2
O
3
(Gd
2
O
3
) [GGO] has been employed for passivating InGaAs and Ge, without using any interfacial paissivation layers (IPLs). The GGO/InGaAs and /Ge metal-oxide-semiconductor capacitors (MOSCAPs) have exhibited low capacitance-equivalent-thickness (CET) of less than 1nm in GGO, low interfacial densities of states (D
it
's) ∼ 10
¹¹
eV
⁻¹
cm
⁻²
, and thermal stability at high temperatures. The high-quality GGO and interfaces of GGO/InGaAs, and /Ge enable the fabrications of inversion-channel InGaAs and Ge MOS field-effect-transistors (MOSFETs) using a self-aligned process, leading to high drain currents, transconductances (G
m
), and carrier mobilities.