Improvement of Electrical Performance of InGaZnO/HfSiO TFTs with 248-nm Excimer Laser Annealing

The influence of 248-nm KrF excimer laser annealing (ELA) with energy density between 0 and 400 mJ/cm(2) on the electrical behavior of indium gallium zinc oxide (InGaZnO) thin-film transistors (TFTs) is investigated. The experimental results show that the saturation mobility and subthreshold swing are improved from 12.4 cm(2)/Vs and 100 mV/dec without ELA to 17.8 cm(2)/Vs and 75 mV/dec, respectively, by applying a 300 mJ/cm(2) laser pulse after the source/drain deposition, while maintaining an almost unchanged turn-off voltage. Such improvements are attributed to the increase in the oxygen vacancies and reduction in the bulk traps in the InGaZnO channel.