The 15th IEEE International Conference on Electron Devices and Solid-State Circuits (EDSSC)

671 / 2019-04-12 16:54:22

Fast Improved Thin-Film Transistors with Atomic-Layer-Deposited In2O3 Channels via O2 Plasma Treatment

In2O3, thin-film transistors, O2 plasma, gate bias stress

Plenary track > Nanoelectronics

High performance thin-film transistors (TFTs) with atomic-layer-deposited In2O3 channel and Al2O3 gate dielectric were fabricated under a maximum process temperature of 200oC. As-fabricated and O2 annealed devices show a conductor-like behavior because of very high carrier concentration in the channels. Compared to the O2 annealing, the O2 plasma treatment can be a much more efficient approach for fast improvement of TFTs by substantially reducing the amount of oxygen vacancies. The In2O3 TFT treated by O2 plasma demonstrates a field-effect mobility of 11 cm2V-1s-1, a threshold voltage of 0.9 V, a subthreshold swing of 0.38 V/dec, and an on/off current ratio of 107. Moreover, the device stability is enhanced markedly if the treatment temperature increases. This could be mainly due to the decrease of -OH/CO groups in the In2O3 film, which is evidenced by X-ray photoelectron spectroscopy.