Comparative Study of MDMO-PPV Thin-Film Transistors Using Thermal SiO2 and PECVD Silicon Oxynitride as Insulator

Abstract

We demonstrate that PECVD SiOxNy with good dielectric properties can replace SiO2 in Organic Thin-Film Transistors (OTFT) applications. It can be used on ITO-covered glass or even flexible substrates thanks to the low deposition temperatures. Poly [2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV) is used as the active layer, due to its wide range of applications such as solar cells, light-emitting diodes and light-emitting transistors. We show also that charge carrier mobility can be at least two times higher for silicon oxynitride on p+-Si substrate than silicon dioxide, ≈ 1.1×10-4 cm2.V-1.s-1, which could be further improved by surface treatments.