Room temperature pulsed laser deposited indium gallium zinc oxide channel based transparent thin film transistors

Abstract

Indium gallium zinc oxide deposited by pulsed laser deposition at room temperature was used as a channel layer to fabricate transparent thin film transistors with good electrical characteristics: field effect mobility of 11cm2V−1s−1 and subthreshold voltage swing of 0.20V∕decade. By varying the oxygen partial pressure during deposition the conductivity of the channel was controlled to give a low off-current of ∼10pA and a drain current on/off ratio of ∼5×107. Changing the channel layer thickness was a viable way to vary the threshold voltage. The effect of the gate dielectric on the electrical behavior was also explored.