Structure and Secondary Electron Emission Coefficient of Diamond Films Deposited by Hot-filament CVD

Abstract

Hot-filament chemical vapor deposition (CVD) of diamond was used to obtain polycrystalline diamond thin film electrodes on silicon substrates. Deposition was carried out by using a mixture of CH₄/H₂ gases through a heated reactor in which a hot tungsten filament was held near the substrates. The films were evaluated by using a scanning electron microscope (SEM), Raman spectroscopy, and a photoacoustic method. The breakdown voltages for the electrodes of the CVD diamond thin films were measured under various Ne pressures by using a V-Q Lissajous method. The secondary electron emission coefficient of the diamond thin film electrodes increased as Raman spectra intensity at 1333 cm^-1 and optical penetration depth increased.