High-performance IZTO TFTs using solution-processed ion-conducting dielectric

Abstract

Li5AlO4 is traditionally known for its application as a solid-state electrolyte. In the present work, we have demonstrated the potential of Li5AlO4 as a gate dielectric material for metal oxide thin film transistors (TFTs) because of its remarkably high dielectric constant (k), which has been achieved by harnessing the enhanced capacitance offered by mobile lithium ions (Li+) within the dielectric film. Our innovative synthesis approach involves a cost-effective sol-gel method followed by a low-temperature annealing process. Through comprehensive experimentation and analysis, we demonstrate the outstanding performance of Li5AlO4 as a gate dielectric. The TFT fabricated by using IZTO as a semiconductor channel layer shows high device performance at low operating voltage (≤ 2.00 V) and high carrier mobility. The highest carrier mobility 4.52 cm2V-1s-1 was obtained with Li5AlO4 dielectric TFT with a very high on/off ratio (∼1.4 × 103) with subthreshold swing (∼240 mV/decade). We have also compared the experimental data with TCAD simulation. © 2024 Author(s).