Effects of proton irradiation on indium zinc oxide-based thin-film transistors

In this research, we performed a high-dose proton-beam irradiation process to investigate the effect of irradiation on the performance of indium-doped zinc oxide-based thin-film transistors (IZO-TFTs) by controlling their electrical and structural properties. The resistivity of IZO thin films dramatically increased with increasing proton-irradiation doses up to similar to 10(14) cm(-2), after which the resistivity recovered to a level similar to as-deposited IZO thin film. After proton irradiation, the crystallinity of IZO thin films was reduced due to defect-isolation and/or chemical-isolation. The field effect mobility of IZO-TFTs decreased from 2.20 cm(2) V-1 s(-1) to 1.22 cm(2) V-1 s(-1), turn-on voltage shifted -7 V to -21 V and subthreshold swing value increased after proton irradiation with a 10(12) cm(-2) dose. With proton-irradiation doses over 10(14) cm(-2), IZO-TFTs device performance recovered to a level similar to that of a pristine device. Moreover, irradiated thin films and devices have low sensitivities to post-thermal annealing due to the creation of antisite oxygen point defects. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.