Optimization of amorphous TiOx-based thin film transistors fabricated by dc magnetron sputtering

Abstract

Listen

Translate article

Amorphous TiOx semiconductor-based thin-film transistors (TFTs) have been optimized with respect to key parameters, such as rapid thermal annealing (RTA) temperature, ambient gas type, and direct current power during sputtering of the TiOx semiconductor layer. It was found that the performance of TiOx semiconductor-based TFTs including field-effect mobility (μFE), sub-threshold swing (SS), on current (Ion), off current (Ioff), on-to-off current ratio (Ion/off), and interface charge traps (Dit) were significantly influenced by such key parameters. Conductivity of the amorphous TiOx semiconductor layer and Ion values were critically dependent on the RTA temperature, whereas switching properties and Ioff values of the TiOx TFTs were influenced by the ambient gas type during the RTA process. At an RTA temperature of 500 °C under N2 flow, we achieved amorphous TiOx semiconductor based TFTs with a μFE of 0.29 cm2/V s, an SS of 2.08 V/decade, and a Dit of 7.32 × 1012 eV−1 cm−2.