The Deterioration Phenomenon of Amorphous InSnZnO Transistors Derived from the Process of Annealing

Thin-film transistors (TFTs) with transparent amorphous indium-tin-zinc-oxide (a-ITZO) channel were fabricated. The field effect mobility (μ) of the a-ITZO TFT was more than 15.0 cm 2 V −1 s −1 , which is higher than the generally reported value of amorphous indium-gallium-zinc-oxide (a-IGZO) TFT. However, μ deteriorated with a decreasing channel length of the a-ITZO TFT due to the annealing process after patterning of the ITZO. We studied the effects of the annealing process on the contact resistance between the a-ITZO film and the source/drain electrodes. A transmission line method (TLM) chart indicated that the parasitic resistances between the source/drain electrode and the back-channel region of the a-ITZO was 2 × 10 4 Ω.