61.1: Invited Paper: ZnO Thin Film Transistors and Circuits on Flexible Polymeric Substrates by Low-Temperature PEALD

We report using a novel, weak oxidant, plasma-enhanced atomic layer deposition (PEALD) process at 200 °C to fabricate stable, high mobility ZnO thin film transistors (TFTs) and fast circuits on glass and polyimide substrates. Weak oxidant PEALD provides a simple, fast deposition process that results in uniform, conformai semiconductor and dielectric layers and enhancement-mode MOSFETs from uncompensated films. Highly conformai PEALD Al2O3 layers provide a high yield dielectric on rough plastic substrates for both PEALD ZnO TFTs and cross-overs. Our PEALD ZnO TFTs have field-effect mobility of >20 cm2/V·s on polyimide substrates with excellent bias stress stability. TFTs biased continuously for 40,000s showed