High-mobility hydrogenated polycrystalline InO (InO:H) thin-film transistors.

Oxide semiconductors have been extensively studied as active channel layers of thin-film transistors (TFTs) for electronic applications. However, the field-effect mobility (μ) of oxide TFTs is not sufficiently high to compete with that of low-temperature-processed polycrystalline-Si TFTs (50-100 cmVs). Here, we propose a simple process to obtain high-performance TFTs, namely hydrogenated polycrystalline InO (InO:H) TFTs grown via the low-temperature solid-phase crystallization (SPC) process. InO:H TFTs fabricated at 300 °C exhibit superior switching properties with µ = 139.2 cmVs, a subthreshold swing of 0.19 Vdec, and a threshold voltage of 0.2 V. The hydrogen introduced during sputter deposition plays an important role in enlarging the grain size and decreasing the subgap defects in SPC-prepared InO:H. The proposed method does not require any additional expensive equipment and/or change in the conventional oxide TFT fabrication process. We believe these SPC-grown InO:H TFTs have a great potential for use in future transparent or flexible electronics applications.