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A waterless cleaning method of Cu foil for chemical vapor deposition (CVD) graphene growth is proposed in this work. In our method, the Cu foil is first annealed in high temperature air and then cooled rapidly, contaminated Cu surface layer was oxided in annealing and separated in the following cooling process, so as to get a clean Cu surface, the whole process does not require the participation of water and other reagents. Due to the influence of oxygen, the density of graphene domains on the waterless cleaning substrate is even lower than that on the polished substrate. Waterless cleaning provides a simple, economical and environment friendly.

This study investigated the influence of the copper substrate surface fluctuations on the transfer of graphene fabricated via chemical vapor deposition. Typical fluctuations, such as reconstructed stripes, grain boundaries, and mechanical creases on Cu surface were explored. The upper graphene which have consistent morphology with the fluctuations were not incompletely copied into the target but by rearrangement after the transfer process. Moreover, some fluctuations may induce damage or glue residual formation in the transfer process.

Chloroplatinic acid (H 2 PtCl 6 ·6H 2 O) was used to modify the grain boundaries of graphene films grown by chemical vapor deposition. Modification occurred only on the edge of the graphene layer in contact with Cu substrate. The grain boundaries of the continuous graphene films were directly observed after modification by optical microscopy and scanning electron microscopy. Energy-dispersive spectroscopy was also used to prove that only Pt nano-particles were modified on the grain boundaries. After chloroplatinic acid modification, the electrical properties of the graphene continuous films were optimized by Hall testing.

As chemical vapor deposition (CVD) graphene is polycrystalline, its electrical and mechanical properties can be improved significantly by increasing the size of the single-crystal domains of graphene. In this report, round-shape millimeter-size graphene domains were prepared on copper (Cu) foil by the atmospheric pressure chemical vapor deposition (APCVD) method using controllable reduction of methane (CH4). The influences of the flow mass of CH4 and the growth temperature of the graphene nucleation density were also studied in detail. The results demonstrated that the initial nucleation density increased with the increase of CH4 and the decrease of growth temperature. The measurements of optical microscopy and Raman spectra indicated that the graphene domains were monolayers with high crystal quality and good uniformity.

Studies of optimization and characteristics of a dry film photopolymerizable recording material are presented. The effect of variation of the concentration of each component was investigated. Diffraction efficiencies of 55%, with the energetic sensitivity of 60 mJ/cm 2 , have been obtained in the photosensitive films of 150-μm thickness with a spatial frequency of 2750 lines/mm. An image has been successfully stored in the material with a small distortion.

In this paper, electron field emission properties and fluorescent displays of 300 nm thick nitrogen-containing diamond-like carbon (DLC:N) films are reported. The films were deposited on to highly n -doped Si (111) substrates by filtered arc deposition (FAD) with different N 2 partial pressures (0.01, 0.05, 0.1 Pa) in the deposition chamber. Their electron field emission properties were studied using a simple diode structure. It was shown that the DLC:N film possessed enhanced field emission properties when a N 2 pressure of 0.05 Pa was used. Emission current of 0.1 μA was detected under the electric field of 8.1 V/μm. An emission current density of 0.204 mA/cm 2 was obtained under 17.8 V/μm.

In this work, amorphous diamond (a-D) films have been prepared by filtered arc deposition (FAD). Field emission data from the a-D film were obtained using planar diode structure. Emission currents in the range of 20–40 μ A were detected at an electric field of 20 V μ m −1 . A mechanism for electron emission from the a-D film is discussed. FAD a-D films had a low effective work function (1.0 eV) and negative electron affinity (−0.2 eV). In addition, uniform and stable emission can be achieved for FAD a-D films.

The results of studies of the surface morphology of nitrogen doped tetrahedral amorphous carbon (ta-C) films with atomic force microscopy (AFM) are reported. The films were prepared by filtered arc deposition (FAD). N is introduced into the films during growth by injecting N 2 gas into a plasma stream formed by a carbon cathode vacuum arc. AFM revealed that the surface on formed films is uniform and smooth on the nanometerscale and the root-mean-square roughness of the films surface is calculated to be approximately 0.23–0.26 nm. The influence of N doping on the surface morphologies of ta-C films are discussed.

In the present work, filtered arc deposition (FAD) and ion assisted arc adposition (IAAD) techniques have been used to deposit amorphous carbon (a-C) and carbon nitride (a-CN) films. Atomic and electronic structures of a-C films have been characterized by electron diffraction and electron energy loss spectra (EELS). In addition, the properties of a-C and a-CN films have been investigated with respect to field emission behavior and optical properties.

CN x films on silicon (111) wafer, quartz and Ti C substrates with nitrogen concentration up to 20 at% have been prepared by a new plasma deposition technique-filtered arc deposition. The nitrogen concentration and area density of the films were measured by Rutherford back-scattering. The optical properties of the films were characterized by ultravioletvisible and infrared reflection spectrometry. Results indicate that the optical band gap and area density of the CN x films decrease with increasing nitrogen pressure, accompanied with an increase of nitrogen concentration and reflectivity of the films. Furthermore, the influence of nitrogen pressure on the optical band gap of the films is discussed.