High performance N-type organic thin-film transistor based on biocompatible silk fibroin: poly(vinyl alcohol)-blended dielectric layer

摘要

We investigated the effect of biocompatible silk fibroin (SF):poly(vinyl alcohol) (PVA) blended dielectric layers on thecharacteristics of N-type organic thin-film transistors (OTFTs). The OTFT with high performance and low drivingvoltage (4 V) are obtained. Compared with those with pure SF dielectric layer, a high on/off ratio of ∼ 10~3 and enhancedfield-effect mobility of 0.203 cm~2/Vs of OTFTs were obtained, by controlling the weight ratio of SF:PVA blends to 7:5.The mechanism of performance improvement of OTFT was systematically studied through the morphologycharacterization of dielectrics by utilizing atom force microscopy and electrical characterization. The smooth andhomogeneous morphology of blend dielectrics having lower charge carrier trap density, is the main reason for the OTFTsbased on SF: PVA-blended dielectric exhibited a higher performance than those based on pure SF dielectric.