Large-area(64 × 64 array) inkjet-printed high-performance metal oxide bilayer heterojunction thin film transistors and n-metal-oxide-semiconductor(NMOS) inverters

It is a big challenge to construct large-scale,high-resolution and high-performance inkjet-printed metal oxide thin film transistor（TFT） arrays with independent gates for the new printed displays.Here,a self-confined inkjet printing technology has been developed to construct large-area（64 × 64 array）,highresolution and high-performance metal oxide bilayer（In2O3/IGZO） heterojunction TFTs with independent bottom gates on transparent glass substrates.Inkjet printing In2O3 dot arrays with the diameters from 55 to 70 μm and the thickness of ～10 nm were firstly deposited on UV/ozone treated Al Oxdielectric layers,and then IGZO dots were selectively printed on the top of In2O3 dots by self-confined technology to form In2O3/IGZO heterojunction channels.When the inkjet-printed IO layers treated by UV/ozone for more than 30 min or oxygen plasma for 5 min prior to print IGZO thin films,the mobility of the resulting printed In2O3/IGZO heterojunction TFTs are correspondingly enhanced to be 18.80 and 28.44 cm2 V-1 s-1 with excellent on/off ratios（>108） and negligible hysteresis.Furthermore,the printed N-Metal-OxideSemiconductor（NMOS） inverter consisted of an In2O3/IGZO TFT and an IGZO TFT has been demonstrated,which show excellent performance with the voltage gain up to 112.The strategy demonstrated here can be considered as general approaches to realize a new generation of high-performance printed logic gates,circuits and display driving circuits.