Recent demonstration of mobilities in excess of 10 cm2 V–1 s–1 have energized research in solution deposition of polymers for thin film transistor applications. Due to the lamella motif of most soluble, semiconducting polymers, the local mobility is intrinsically anisotropic. Therefore, fabrication of aligned films is of interest for optimization of device performance. Many techniques have been developed to control film alignment, including solution deposition via directed flows and deposition on topologically structured substrates. We report device and detailed structural analysis (ultraviolet–visible absorption, IR absorption, near-edge X-ray absorption (NEXAFS), grazing incidence X-ray diffraction, and atomic force microscopy) results from blade coating two high performing semiconducting polymers on unpatterned and nanostructured substrates. Blade coating exhibits two distinct operational regimes: the Landau–Levich or horizontal dip coating regime and the evaporative regime. We find that in the evaporative deposition regime, aligned films are produced on unpatterned substrates with the polymer chain director perpendicular to the coating direction. Both NEXAFS and device measurements indicate the coating induced orientation is nucleated at the air interface. Nanostructured substrates produce anisotropic bottom contact devices with the polymer chain at the buried interface oriented along the direction of the substrate grooves, independent of coating regime and coating direction. Real time studies of film drying establish that alignment occurs at extremely high polymer volume-fraction conditions, suggesting mediation via a lyotropic phase. In all cases the final films appear to exhibit high degrees of crystalline order. The independent control of alignment at the air and substrate interfaces via coating conditions and substrate treatment, respectively, enable detailed assessment of structure–function relationships that suggest the improved performance of the nanostructure aligned films arise from alignment of the less ordered material in the crystallite interphase regions.

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We prepared alternating CNx/TiN composite films using a dc magnetron sputtering system in which a closed unbalanced magnetic field was adopted and a negatively biased grating was placed in front of each substrate. The composition of the thin film was analyzed by X-ray photoelectron spectroscopy (XPS). X-ray diffraction (XRD) and transmission electron diffraction (TED) revealed that the CNx films deposited at grating voltages lower than 400V are amorphous. β-C3N4 and subic-C3N4(c-C3N4) were formed at higher voltages. A high grating voltage is indispensable for synthesis of c-C3N4. The lattice constants of C3N4 evaluated from the experimental data agree well with reported theoretical values.

Nitride carbon thin films have been deposited by plasma-enhanced chemical vapor phase deposition. The results of transmission-electron diffraction indicated that films have polycrystal structures. Carbon and nitrogen atoms binding energies and the nitrogen content of the-films are measured out by X-ray photoelectron spectroscopy.The Fourier transform infrared spectrum show that there is no graphite phase in the films,and the Vickers hardness of the films vary from 29.2 to 50.0GPa.

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