The effect of the thickness and oxygen ratio control of radio-frequency magnetron sputtering on MgZnO thin-film transistors

In this study, we use silicon dioxide for a magnesium-zinc-oxide thin-film transistor gate dielectric layer, controlling the thickness of the active layer and the Mg content of the film by radio-frequency (RF) sputtering. With an ideal thickness, a magnesium-zinc-oxide thin-film transistor can function normally. As the active layer thickness is controlled at 10 nm and the sputtering oxygen-flow rate is controlled at 14% to properly compensate for the oxygen vacancies, we can obtain the best features. The result of the analysis showed a field-effect mobility of 5.65 cm²/V·s, a threshold voltage of 3.1 V, a subthreshold swing improved to 0.80, and a current-switch ratio of over five orders of magnitude.