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

• Published in: NPJ 2D materials and applications 2022-03, Vol.6 (1), p.1-8, Article 16
• Main Authors: Hamlin, Andrew B., Ye, Youxiong, Huddy, Julia E., Rahman, Md Saifur, Scheideler, William J.
• Format: Article
• Language: English
• Subjects: 639/301/1005/1007; 639/301/357/1018; 639/766/119/995; Channels; Chemistry and Materials Science; Electronics; Indium; Liquid metals; Low temperature; Materials Science; Metal oxides; Nanotechnology; Quantum confinement; Semiconductor devices; Surfaces and Interfaces; Thin film transistors; Thin Films; Transistors
• ISSN: 2397-7132; 2397-7132
• DOI: 10.1038/s41699-022-00294-9

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) InO x . These continuous nanosheets are rapidly (60 cm s −1 ) printed over large areas (30 cm 2 ) directly from the native oxide skin spontaneously formed on molten indium. These nanocrystalline LMP InO x 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 InO x channels, yielding thin-film transistors with ultrahigh mobility (μ 0  = 67 cm 2 V −1 s −1 ), excellent current saturation, and low hysteresis at temperatures down to 165 °C. This work establishes LMP 2D InO x as an ideal low-temperature transistor technology for high-performance, large area electronics such as flexible displays, active interposers, and thin-film sensors.