One-step fabrication of high-performance organic field-effect transistors from semiconductor/dielectric blends

Abstract

Vertical phase separation of organic semiconductor/dielectric polymer blends has been used in field-effect transistors (FETs) to fabricate low-voltage devices, improve environmental stability, and reduce semiconductor cost. However, all structures reported in previous studies are dielectric-up and semiconductor-bottom structures, and it is difficult to combine multi-advantages in one system because special materials and methods are used in each case. Here, we first fabricated a semiconductor-top and dielectric-bottom bilayer structure by surface-induced vertical phase separation of conjugated molecules and insulating polymer blends. The use of these bilayered blends as active layer in FETs leads to an improvement of the device performance with a drastic reduction of semiconductor content because insulating polymer layer can act as modifier at the semiconductor/dielectric interface. Moreover, because the insulting polymer layer can be used as dielectric layer without any other dielectrics, the blended films can be used to fabricate high-performance, lowsemiconductor-content, and low-voltage FETs in a one-step process.