title: Boundary layer profiles in plasma chemical vapor deposition.
abstract: A nonlinear optical spectroscopy based on degenerate four-wave mixing has made possible direct measurements of species temperature and concentration profiles through the boundary layer of a reactive plasma at atmospheric pressure. Spectra were obtained for CH and C(2) radicals over a range of conditions including those for the plasma chemical vapor deposition of diamond films. Numerical simulations based on a one-dimensional stagnation-point flow model are in good agreement with the measurements. The CH mole fraction is shown to rise and fall as a function of distance from the substrate, which is compelling experimental evidence for the complex chemistry that is occurring in the plasma boundary layer.
authors.forename: D S
authors.initials: DS
authors.lastname: Green
authors.forename: T G
authors.initials: TG
authors.lastname: Owano
authors.forename: S
authors.initials: S
authors.lastname: Williams
authors.forename: D G
authors.initials: DG
authors.lastname: Goodwin
authors.forename: R N
authors.initials: RN
authors.lastname: Zare
authors.forename: C H
authors.initials: CH
authors.lastname: Kruger