Ultrathin Atomic-Layer-Deposited In<sub>2</sub>O<sub>3</sub> Radio-Frequency Transistors with Record High f<sub>T</sub> of 36 GHz and BEOL Compatibility
Dongqi Zheng, Adam Charnas, Jian-Yu Lin, Jackson Anderson, Dana Weinstein, Peide D. Ye
Abstract
In this work, we report back-end-of-line (BEOL) compatible In <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> O <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> RF transistors with cut-off frequencies (f <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</inf> ) up to 36GHz, which is the highest among all metal oxide semiconductor channel RF transistors to date. Due to the outstanding transport properties and high scalability of In <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> O <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> , record-high f <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</inf> value can be achieved with V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">DS</inf> at $0.8 \mathrm{~V}$ and V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">GS</inf> at −0.8 V on 2-nm thick, 40 nm-long channel devices. This work demonstrates the first ever BEOL oxide RF transistor with mm-Wave band operation frequency. In addition to improve the performance at Si CMOS clock frequencies for 3D integrated circuits (IC), it also offers the possibility for potential applications in future energy-efficient 6 G wireless communication devices.