Synthesis, spectral characterization of CuPcF16 and its application in organic thin film transistors using p-6p as inducing layer Original Research Article

An air-stable n-channel semiconductor material, CuPcF16, was synthesized in a slightly modified procedure and characterized by infrared (IR), X-ray diffraction (XRD), UV–vis and fluorescence spectra. CuPcF16 showed a monomer characteristic in THF and pyridine while exhibited an aggregation property in DMF. The CuPcF16/p-6p (CuPcF16 on p-6p) organic thin film transistors (OTFTs) using CuPcF16 as an active layer and p-6p as an inducing layer was fabricated by the physical vapor deposition technique. Charge carrier field-effect mobility (μ), Ion/Ioff and threshold voltage (VT) of the CuPcF16/p-6p OTFTs were 0.07 cm2/V s, 105 and 5.28 V, respectively. The charge mobility of the OTFTs was two or even three times higher than that of the conventional single layer CuPcF16-based OTFTs. The improved performance was attributed to the introduction of p-6p to form a highly oriented and continuous film of CuPcF16 with the molecular π–π conjugated direction parallel to the substrate.