Room-Temperature Fabrication of High-Performance H doped ZnO Thin-Film Transistors

Abstract We prepared ZnO:H thin films in Ar+H2 atmosphere with substrate at room temperature by magnetron sputtering, the effect of H2 flow ratio on the properties of thin films and the performance of ZnO:H thin-film transistors (ZnO:H-TFTs) were investigated. Hydrogen could act as a defect passivator and a shallow donor in ZnO films, which not only increases the carrier concentration but also reduces the interface trap density, therefore improving the TFT performance. Compared with pristine ZnO-TFT, the optimal ZnO:H-TFT exhibits great enhancement, with the field-effect mobility increasing from 2.17 cm2/Vs to 5.17 cm2/Vs, the on/off ratio increasing from 3.47×105 to 4.98×106, the threshold voltage reducing from 15.12 V to 6.03 V. Meanwhile, the positive and negative bias stability is also improved from ΔVth=3.89 V and -6.35 V to 1.74 V and -3.72 V, respectively. Our results show that introducing hydrogen into the sputtering atmosphere to achieve hydrogen doping is a simple and effective method to improve the performance of ZnO-TFTs. Furthermore, the high-performance ZnO:H-TFTs fabricated at room temperature have great potential in the field of flexible electronics.