Low-temperature processing of inkjet-printed IZO thin-film transistors

Inkjet-printed indium-zinc oxide (IZO) thin-film transistors (TFTs) were prepared at a processing temperature of 200 °C for the first time. The formulation of the inkjet solution and the process optimization resulted in a mobility of 0.45 cm2/Vs, a threshold voltage of 7 V, an on-to-off current ratio of 105 and a subthreshold slope of 0.5 V/dec at the low annealing temperature of 200 °C, the best properties in the inkjet process thus far. The metal-oxide formation at 200 °C was confirmed by using X-ray photoelectron Spectroscopy. The bias stability of an inkjet-printed IZO TFT at 200 °C was also characterized.