Realization of Maximum 2 A/mm Drain Current on Top-Gate Atomic-Layer-Thin Indium Oxide Transistors by Thermal Engineering

In this work, we demonstrate the record high maximum drain current ( ${I}_{{\mathrm {D}}}$ ) of 2 A/mm of top-gate (TG) indium oxide (In ₂ O ₃ ) transistors. The scaled and atomic-layer-deposited (ALD) In ₂ O ₃ transistors have channel length ( ${L}_{{\mathrm {ch}}}$ ) down to 40 nm and channel thickness ( ${T}_{{\mathrm {ch}}}$ ) down to 1.3 nm. Besides, the thermal budget of the whole material formation and device fabrication process is as low as 225 °C, making it compatible with back-end-of-line (BEOL) technologies by a huge margin. On the other hand, highly resistive silicon is utilized to serve as a desired high thermal conducting substrate to dissipate the generated heat efficiently as a larger current is conducted under a larger voltage bias. It greatly alleviates the self-heating effect (SHE) and allows an approximately 100% higher drain current. Quantitative studies of the SHE and channel temperature at ON-state with SiO ₂ /Si and highly resistive silicon substrates are also presented.