Switching Properties Improvement of Tungsten-Doped Indium Oxide Phototransistor

High-performance and transparent tungsten-doped indium oxide (InWO) thin-film transistors (TFTs) with aluminum or indium oxide (In2O3) source and drain (S/D) electrodes were fabricated using the radiofrequency (RF) co-sputtering method. Due to the lower electron barrier height of the In2O3/InWO interface, the device with a homojunction structure exhibited better performance (mu (eff) = 20.1 cm(2) V-1 center dot s(-1) and S.S. = 0.17 V dec(-1)) than the one with a heterojunction structure. Moreover, due to the high transparency of the S/D electrode, the light-sensing area was magnified. Thus, the responsivity of the phototransistor was significantly improved from 23.68 A W-1 to 89.47 A W-1. This result improved the properties of the interface between the S/D electrode and the channel layer and simplified the manufacturing process for InWO TFTs.