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, conformal semiconductor and dielectric layers and enhancement-mode MOSFETs from uncompensated films. Highly conformal 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 <50 mV threshold voltage shift. We also report fast PEALD ZnO circuits on polyimide substrates with propagation delay <20 ns/stage for VDD = 18 V.
|Original language||English (US)|
|Number of pages||4|
|Journal||Digest of Technical Papers - SID International Symposium|
|State||Published - May 2010|
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