Search

Abstract: This study reports on the ion-induced secondary electrons emission (SEE) from MgO films deposited on multiwalled carbon nanotubes (MWCNTs). MWCNTs are grown on quartz substrates using plasma enhanced chemical vapor deposition system and MgO films are deposited on that MWCNTs using electron-beam evaporation technique. The SEE coefficients are obtained from experimentally measured firing voltage. We observed stabilized and lower firing voltage of MgO films deposited on MWCNTs than that for MgO. The experimental results suggest that the density, uniformity and alignment of nanotubes influence the local electric field in nano-pores of MgO films which in turn affects the emission of secondary electrons from MgO surface. [Copyright &y& Elsevier]

Abstract: We report on our study of the influence of varying concentrations of Si doping on the secondary electron emission (SEE) yield of MgO thin films prepared by electron beam evaporation technique. The series of Si-doped MgO films were microstructurally characterized with various tools like X-ray diffraction, scanning electron microscopy and atomic force microscopy. The optimization of the concentration of Si doping is seen to enhance the SEE yield. We discuss the correlation of SEE yield in the context of different deposition and measurement conditions and crystalline orientation. [Copyright &y& Elsevier]

Abstract: Plasma enhanced chemical vapor deposition (PECVD) technique using pulsed-DC power supply was used to fabricate diamond like carbon (DLC) films at deposition rates as high as 110 nm/min. The DLC films deposited by pulsed-DC and DC based power supplies under different gas flow ratios were studied for their suitability as dielectric layer coatings in plasma display panels (PDPs). The effect of deposition parameters on the properties of the DLC films were studied using Fourier transform infra-red spectroscopy (FTIR) and spectroscopic ellipsometry (SE). FTIR reveals that higher hydrogen dilution in gas mixture leads to higher sp 3 content. SE studies in wide spectral range were analyzed using Tauc-Lorentz model dielectric function. A rise in the extracted refractive index was seen on increasing the H2 content in the feed gas, thus resulting in optically denser films. Secondary electron emission coefficient (γ) was measured in the films deposited by the DC and pulsed-DC based PECVD. Firing voltage in the DLC samples was found to have very low variation in the operating pressure range used in commercial PDPs, suggesting possibility of enhanced long term reliability of DLC coatings in future PDP applications. [Copyright &y& Elsevier]