Spectroscopic diagnostics of plasma-chemical-vapor deposition from silane and germane

Abstract
Coherent anti-Stokes Raman spectroscopy (CARS), laser-induced fluorescence (LIF), and emission spectroscopy are employed for the diagnostics of radio-frequency discharge plasmas of silane and germane; CARS signal of germane molecule; and LIF signal and ultraviolet emission signal of germanium atom in discharges, as well as signals from nongermanium-related neutral species are measured. The effect of hydrogen dilution on emission signal intensities in the steady-state discharge explains dynamic behaviors of the emission and CARS signal intensities in the closed discharge; these spectroscopic techniques are powerful diagnostic tools for gas-phase processes using mixed gas sources.