Universal solution-processed high-k amorphous oxide dielectrics for high-performance organic thin film transistors

Abstract

Solution-processed high-k dielectrics for organic thin film transistors (OTFTs) have been widely studied with the objective of achieving high-performance and low cost OTFTs for next-generation electronics. In this study, we introduce a universal solution fabrication of high-k amorphous oxide dielectrics for high-performance OTFTs. The amorphous oxide films by solution processes feature a smooth surface, uniform composition and excellent dielectric properties. With ZrTiO_x as a typical example, a k value and capacitance as high as 53 and 467 nF cm⁻² could be achieved. The polystyrene (PS) modification of ZrTiO_x dielectric films results in a leakage current as low as 4 × 10⁻⁸ A cm⁻². Based on their implementation as a gate insulator, the solution-processed high-k ZrTiO_x dielectric films realize high and stable performance OTFTs during operation at a low-voltage. A carrier mobility of 0.58 cm² V⁻¹ s⁻¹, an on/off current ratio of 10⁴, and a low operating voltage of 6 V were achieved through simple control of the annealing temperature. Our results show the possibility of the solution-processed high-k amorphous oxide dielectric layer as a gate insulator for OTFTs. We believe that these high-k amorphous oxide dielectric films offer great potential for next-generation high-performance organic electronics, especially low-voltage electronics.