2D transistors rapidly printed from the crystalline oxide skin of molten indium

Abstract

Abstract Ultrathin single-nm channels of transparent metal oxides offer unparalleled opportunities for boosting the performance of low power, multifunctional thin-film electronics. Here we report a scalable and low-temperature liquid metal printing (LMP) process for unlocking the ultrahigh mobility of 2-dimensional (2D) InOx. These continuous nanosheets are rapidly (60 cm s−1) printed over large areas (30 cm2) directly from the native oxide skin spontaneously formed on molten indium. These nanocrystalline LMP InOx films exhibit unique 2D grain morphologies leading to exceptional conductivity as deposited. Quantum confinement and low-temperature oxidative postannealing control the band structure and electronic density of states of the 2D InOx channels, yielding thin-film transistors with ultrahigh mobility (μ0 = 67 cm2 V−1s−1), excellent current saturation, and low hysteresis at temperatures down to 165 °C. This work establishes LMP 2D InOx as an ideal low-temperature transistor technology for high-performance, large area electronics such as flexible displays, active interposers, and thin-film sensors.