Indium–Tin-Oxide Transistors with One Nanometer Thick Channel and Ferroelectric Gating
Mengwei Si, Joseph Andler, Xiao Lyu, Chang Niu, Suman Datta, Rakesh Agrawal, Peide D. Ye
Abstract
In this work, we demonstrate high-performance indium–tin-oxide (ITO) transistors with a channel thickness down to 1 nm and ferroelectric Hf0.5Zr0.5O2 as gate dielectric. An on-current of 0.243 A/mm is achieved on submicron gate-length ITO transistors with a channel thickness of 1 nm, while it increases to as high as 1.06 A/mm when the channel thickness increases to 2 nm. A raised source/drain structure with a thickness of 10 nm is employed, contributing to a low contact resistance of 0.15 Ω·mm and a low contact resistivity of 1.1 × 10–7 Ω·cm2. The ITO transistor with a recessed channel and ferroelectric gating demonstrates several advantages over 2D semiconductor transistors and other thin-film transistors, including large-area wafer-size nanometer thin-film formation, low contact resistance and contact resistivity, an atomic thin channel being immune to short channel effects, large gate modulation of high carrier density by ferroelectric gating, high-quality gate dielectric and passivation formation, and a large bandgap for the low-power back-end-of-line complementary metal-oxide-semiconductor application.