High thermal tolerance of 25-nm c-axis aligned crystalline In-Ga-Zn oxide FET

Abstract

We developed FETs having gate lengths of 25 and 60 nm that are suited for high-temperature operation, using c-axis aligned crystalline In-Ga-Zn oxide (CAAC-IGZO) as its channel material. The FETs with a gate length of 60 nm achieved off-state leakage currents of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-20</sup> A at 150°C. Furthermore, cutoff frequency the FETs with a gate length of 25 nm was 33 GHz at room temperature and changing the temperature from room temperature to 150°C changed the cutoff frequency by only -13% against -36% in Si FET. The CAAC-IGZO FET enables integrated circuits that consume little power even under high-temperature environments.