Self-aligned Inversion-channel In{sub}0.75Ga{sub}0.25As MOSFETs using MBE-Al{sub}2O{sub}3/Ga{sub}2O{sub}3(Gd{sub}2O{sub}3) and ALD-Al{sub}2O{sub}3 as Gate Dielectrics

摘要

High-performance self-aligned inversion-channel In{sub}0.75Ga{sub}0.25As n-MOSFETs using in-situ ultra-high-vacuum (UHV) deposited Al{sub}2O{sub}3/Ga{sub}2O{sub}3(Gd{sub}2O{sub}3) and ex-situ atomic-layer-deposited (ALD) Al{sub}2O{sub}3 as gate dielectrics have been fabricated. Both devices exhibit excellent DC characteristics, including high drain currents and transconductances. A 1.2μm-gate-length In{sub}0.75Ga{sub}0.25As MOSFET using Al{sub}2O{sub}3(2nm-thick)/GGO(13nm-thick) dual-layer gate dielectric demonstrated a maximum drain current of 970μA/μm, a peak transconductance of 410μS/μm, and a peak mobility of 1560cm{sup}2/V·s. A maximum drain current of 194μA/μm and a peak transconductance of 126μS/μm were exhibited by a 2μm-gate-length In{sub}0.75Ga{sub}0.25As MOSFET using ALD-Al{sub}2O{sub}3(6nm-thick).