Effective Evaluation Strategy Toward Low Temperature Solution-Processed Oxide Dielectrics for TFT Device

Abstract

Solution-processed oxide dielectrics are widely studied as alternatives to SiO2, SiNx in thin film transistors for high capacitance and low energy consuming. However, it's still a challenge to achieve high quality of solution-processed oxide dielectrics TFT by low-temperature post-treatment. Here, an effective strategy is proposed to evaluate low temperature solution-processed ZrO2 TFT in terms of uniformity, film density and electrical performance by employing TG/DSC, drop analyzer, XRR and a novel μ -PCD measurement. Particularly, μ -PCD measurement provides valuable information on homogeneity and defect level. The optimized device with ZrNO3 as dielectric precursor and ethyl alcohol as solvent through spin coating process annealed at 200°C shows a saturation mobility of 8.6 cm ^{2}\text{V}^{-1}\text{S}^{-1} , IonIoff ratio about 1.1× 106 , subthreshold swing about 334 mV/decade with a low leakage current density of 5× 10-5 A/cm2 at 10V. This article offers a convenient way for precursor optimization towards low leakage current and high homogeneity solution-processed oxide dielectrics for TFT devices.