Comparative Study of MDMO-PPV Thin-Film Transistors Using Thermal SiO_2 and PECVD Silicon Oxynitride as Insulator

摘要

We demonstrate that PECVD SiO_xN_y with good dielectric properties can replace SiO_2 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, μ_h ≈ 1.1×10~(-4) cm~2.V~(-1).s~(-1), which could be further improved by surface treatments.