  In this work, we demonstrate atomic-layer-deposited (ALD) single-channel
indium oxide (In2O3) gate-all-around (GAA) nanoribbon FETs in a
back-end-of-line (BEOL) compatible process. A maximum on-state current (ION) of
19.3 mA/{\mu}m (near 20 mA/{\mu}m) is achieved in an In2O3 GAA nanoribbon FET
with a channel thickness (TIO) of 3.1 nm, channel length (Lch) of 40 nm,
channel width (Wch) of 30 nm and dielectric HfO2 of 5 nm. The record high drain
current obtained from an In2O3 FET is about one order of magnitude higher than
any conventional single-channel semiconductor FETs. This extraordinary drain
current and its related on-state performance demonstrate ALD In2O3 is a
promising oxide semiconductor channel with great opportunities in BEOL
compatible monolithic 3D integration.
