Studies of the Time Dependent Reactant Temperatures and Concentrations in RF Nitride Deposition Plasmas Using CARS

摘要

A radiofrequency pulsed plasma enhanced chemical vapor deposition reactor for silicon nitride production was designed, tested, and used to investigate the relationship of the reactor conditions to the depletion of and temperature of gas phase reactants in the rf plasma and to the properties of the deposited silicon nitride thin films and nano-particles. Correlations were found to exist between the depletion of silane and the uniformity of the thin films and particle sizes or also the atomic composition of the thin films and particles. Two methods were implemented to measure the depletion of silane gas in the plasma. Coherent anti-Stokes Raman scattering (CARS) spectroscopy for thin film depositions, and pulsed sampling mass spectrometry (PSMS) for nano- particle deposits. The PSMS instrument represents a new method for sampling pulsed plasmas by mass spectrometry. Insight into the relative roles of gas and surface chemical processes was gained by this work.