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Transparent conductive Al-doped zinc oxide thin films for film solar cells were prepared on Si and quartz substrates by radio frequency magnetron sputtering at room temperature. Then, these films were treated by high-density H2/Ar plasma, which was capacitively coupled plasma combined with inductively coupled plasma modes. The density of hydrogen atoms was characterized by optical emission spectroscopy equipped in the system. The structural, electrical, and optical properties of the films were investigated in terms of spectrophotometry, Hall effect measurements, X-ray diffraction, scanning electron microscope, and atomic force microscopy. The effects of low-frequency power on the optical, electrical, and structural properties were discussed. [ABSTRACT FROM PUBLISHER]

A series of chemical vapor deposition (CVD) precursors have been synthesized by a single‐step reaction of 1,1,3,3‐tetramethylguanidine and a variety of silicon chlorides. The structures of the 1,1,3,3‐tetramethylguanidinate‐based compounds were verified by 1H NMR, 13C NMR, XPS, EI‐MS, and elemental analysis. The thermal stability, transport behavior, and vapor pressures of these compounds were evaluated by simultaneous thermal analyses (STA). These compounds are highly stable and those in liquid form are very volatile. Silicon carbonitride (SiCN) thin films were prepared by using bis (tetramethylguanidine)‐dimethyl‐silane as the precursor in helicon wave plasma chemical vapor deposition (HWP‐CVD). The properties of the films were investigated by SEM, AFM, and XPS. The results showed that the films have good uniformities, low friction coefficient, and high hardness, enabling the films for fabrication of semiconductor devices. [ABSTRACT FROM AUTHOR]

• TiO 2 /SLG composites were fabricated by CVD combined with RF magnetron sputtering for the first time. • A successful reservation of graphene was achieved under the RF magnetron sputtering condition. • The interaction between TiO 2 and SLG was identified by the G band splitting and upshift of the 2D band. • With the SLG as the interface of the TiO 2 /SLG, the composite films showed appreciable photocurrents. Titanium dioxide/single layer graphene (TiO 2 /SLG) composites have been widely studied due to the role of graphene acting as an electron-acceptor, which can suppress the recombination of photogenerated electron–hole pairs from TiO 2 upon light irradiation. In this study, a novel route for the synthesis of TiO 2 /SLG composite films using controlled experiment chemical vapor deposition combined with magnetron sputtering is reported for the first time. The structure and morphology of the SLG and TiO 2 /SLG composites were characterized by scanning electron microscopy, Raman spectroscopy, transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The results showed that the introduction of SLG layer influenced the crystalline structure, morphology and photocurrent of the TiO 2 films. The interaction between TiO 2 and SLG and p-doping of SLG were demonstrated by the G band splitting and upshift of the 2D band. With the higher quality of SLG as the interface of the TiO 2 /SLG, the composite films exhibited improved photocurrent and reached the highest of about 3.25 μA/cm−2. The results suggested the high separation efficiency of photogenerated electron-hole pairs, which could inspire continuous researches of energy conversion and environmental applications. [ABSTRACT FROM AUTHOR]

We investigated the growth process of vertically-oriented graphene nanosheets (VGs) on a Si substrate by helicon wave plasma chemical vapor deposition (HWP-CVD). The results show that VGs has good vertical orientation on Si and the growth process does not require the catalyst. Modulation of height, thickness and mesh size of vertical graphene nanosheets can be achieved by changing the growth time. It is found that the height of VGs is linear with time. Extremely high growth rate, approximately 0.26 μm/min, is achieved, in contrast to previous studies. The results of Cyclic voltammetry (CV) measurement indicating that VGs have a very rapid current–voltage response, an excellent electrochemical reversibility and excellent capacitive behavior. The VGs was able to deliver an outstanding specific capacitance value of 345 μF/cm2, and demonstrated an excellent rate capability, which retained 94.41%. Unlabelled Image • Successful preparation of VGs using high-density HWP-CVD for the first time. • Influence of precursor flow rate on the structure and electrochemical properties of VGs was studied. • The growth process of VGs prepared by HWP-CVD was described for the first time. • The microstructure of VGs has been changed to enhance its capacitance and rate capability. • The preparation of VGs by HWP-CVD has a higher capacitance (345 μF/cm2) value and rate capability (94.41%). [ABSTRACT FROM AUTHOR]