Cellulose nanocrystals thin films as gate dielectric for flexible organic field-effect transistors

We report on the fabrication of flexible field-effect transistor using poly[N-9”-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)] as active channel and cellulose nanocrystals (CNC) as gate dielectric on indium tin-oxide coated polyethyleneterephthalate substrate. The use of CNC as gate dielectric material was found favorable for carrier transport at the semiconductor/dielectric interface with the device showing an on–off ratio of ≈104. These results indicate that CNC is a promising gate dielectric layer for flexible organic field effect transistors.