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A new method to directly grow graphene on quartz glass substrate by atmospheric-pressure chemical vapor deposition (CVD) without using any catalyst was developed. The prime feature of this method is to build a vertical-glass model in the quartz tube to significantly increase the collision probability of the carbon precursors and reactive fragments between each other with the glass surface. The growth rate of high-quality graphene on glass remarkably increases compared with the conventional gas flow CVD technique. The optical transmittance and sheet resistance of the graphene glass can be readily adjusted by regulating growth time. When growth time is 35 min, the graphene glass presents an intriguing sheet resistance of about 1.48 kΩ sq −1 at a transmittance of 93.08% and exhibits an excellent hydrophobic performance. The method is simple and scalable, and might stimulate various potential applications of transparent and conductive graphene glass in practical fields. [ABSTRACT FROM AUTHOR]

TaN x thin films were deposited on commercial polished Al2O3 ceramic substrates by reactive dc magnetron sputtering. The influences of the film thickness on the electrical properties of the samples were examined in detail. It is found that the film thickness does not influence the phase structures of the TaN x thin films. The sheet resistances of the samples shift from 173 Ω/sq. to 7.5 Ω/sq. with the film thickness shifting from 30 nm to 280 nm. With the increase of the film thickness from 30 nm to 280 nm, the temperature coefficient of resistance (TCR) of the samples shifts from negative value to positive value. When the film thickness is about 100 nm, TaN x thin films exhibits a near-zero TCR value (approximately −15×10−6/°C). This fact implies that TaN x thin films with a null TCR can be obtained by adjusting the film thickness. The variation in the electrical properties of the TaN x thin films with the film thickness can be qualitatively explained by the parallel connection of surface layer with high resistivity and negative TCR and TaN x layer with low resistivity and positive TCR. [Copyright &y& Elsevier]