Mobility enhancement by using silk fibroin in F16CuPc organic thin film transistors

High performance n-type F₁₆CuPc organic thin-film transistors (OTFTs) were fabricated on polyethylene terephthalate (PET) using silk fibroin as the gate dielectric. The average field-effect mobility (μ_FE) value in the saturation regime is 0.39 cm² V⁻¹ s⁻¹ approximately one order of magnitude higher than the reported values in the literature. A typical F₁₆CuPc OTFT exhibits an on/off current ratio of 9.3 × 10², a low threshold voltage of 0.65 V, and a subthreshold swing value of 730 mV/decade. The enhancement of μ_FE results from very good crystal quality of F₁₆CuPc on silk fibroin, supported by grazing incidence X-ray diffraction (GIXD) data.