Biocompatible/Degradable Silk Fibroin:Poly(Vinyl Alcohol)-Blended Dielectric Layer Towards High-Performance Organic Field-Effect Transistor

Biocompatible silk fibroin (SF): poly(vinyl alcohol) (PVA) blends were prepared as the dielectric layers of organic field-effect transistors (OFETs). Compared with those with pure SF dielectric layer, an optimal threshold voltage of similar to 0 V, high on/off ratio of similar to 10(4), and enhanced field-effect mobility of 0.22 cm(2)/Vs of OFETs were obtained by carefully controlling the weight ratio of SF: PVA blends to 7:5. Through the morphology characterization of dielectrics and organic semiconductors by utilizing atom force microscopy and electrical characterization of the devices, the performance improvement of OFETs with SF: PVA hybrid gate dielectric layers were attributed to the smooth and homogeneous morphology of blend dielectrics. Furthermore, due to lower charge carrier trap density, the OFETs based on SF: PVA-blended dielectric exhibited a higher bias stability than those based on pure SF dielectric.