Fig. 4From: Biocompatible/Degradable Silk Fibroin:Poly(Vinyl Alcohol)-Blended Dielectric Layer Towards High-Performance Organic Field-Effect TransistorThreshold voltage shifts (ΔV T) of OFETs based pure SF (a) and SF:PVA = 21:5 blends (b), respectively. The bias conditions during the stress were fixed at V GS = −30 V, and the transfer curves were measured at the given time intervals. c Normalized changes in the currents in OFETs under the bias stress of V GS = −30 VBack to article page