Photopatternable ultrathin gate dielectrics for low-voltage-operating organic circuits

Abstract

We report here a photopatternable ultrathin gate dielectric for the fabrication of low-voltage-operating organic field-effect transistors (OFETs) and inverters. The gate dielectric material is composed of a photocrosslinkable polymer, poly(vinyl cinnamate), and a thermally crosslinkable silane crosslinking reagent, 1,6-bis(trichlorosilyl)hexane. The spin-coated dielectric is photocured with ultraviolet light, which enables fine film patterning via regular photolithography. After thermal curing (at 110 degrees C), the dielectric showed excellent insulating properties (a leakage current density of approximate to 10(-7) A/cm(2) at 2.0 MV/cm) for an ultrathin film thickness of 70 nm, thus reducing the operating voltage of the OFETs and inverters to -5 V.