High-mobility transparent amorphous metal oxide/nanostructure composite thin film transistors with enhanced-current paths for potential high-speed flexible electronics

Abstract

We review the improved performance of amorphous oxide semiconductor (AOS) based thin film transistors (TFTs) with embedded nanostructures. Amorphous indium zinc oxide/single-walled carbon nanotube (a-IZO/SWNT) composite TFTs exhibited a high mobility of 140 cm² V⁻¹ s⁻¹ and robust flexibility comparable with those of organic TFTs. Obtaining the optimal device operation performance depends critically on the full control of mobility and threshold voltage (V_th). The V_th was readily tuned to a favourable value, and the device maintained a reasonably high mobility of 132 cm² V⁻¹ s⁻¹. Moreover, the intrinsic cut-off frequency f_T could reach 72 MHz. The amorphous indium zinc/In₂O₃ nanocrystalline (a-IZO/In₂O₃ NC) composite TFTs also demonstrated that the enhanced-current paths could generally improve the mobility of the AOS TFTs. The proposed strategy was reliable and reproducible for large-scale fabrication. The overall high performance indicated that amorphous metal oxide/nanostructure composite TFTs were readily suitable for large-scale low-power radio frequency applications.