Process for Precisely Controlling the Relative Amounts of Evaporant and Gas for Reactive Film Deposition
Original Publication Date: 1985-Mar-01
Included in the Prior Art Database: 2005-Feb-18
In the reactive evaporation of some materials such as cermets, the evaporation rate and reactive gas pressure must be controlled very precisely. A process control method is described for reactive film deposition in which the characteristic emission lines of the various depositing chemical elements are excited and the intensities thereof measured. The deposition process is controlled so that these intensities remain at desired relative values. It is expected that if the ratios of the intensities are held constant, the composition of the depositing film will also remain constant. The evaporation sources are set up such that there is a controlled mechanism for electronically exciting the species in the vapor phase.