CATHODOLUMINESCENCE (CL) AND CL SPECTRA OF MICROWAVE PLASMA-ENHANCED CVD DIAMOND

Recent research work is reported on cold cathode luminescence (CL) mic roscopy and CL microspectrophotometry of diamond produced by means of plasma-activated mixtures of hydrogen and methane gases. Diamond layer s of octahedral, cubooctahedral or cubic habit on SiAlON substrates as well as ballastype layers were investigated. Diamond was also deposit ed on sheet substrates of titanium, niobium, tantalum, chromium, molyb denum, tungsten, iron (spheroidal and lamellar cast iron), cobalt and nickel. Studying CL colors together with CL spectra has proved to be a reliable diagnostic method for differentiating between the morphologi cal properties of CVD diamond on SiAlON substrates. It is however not possible with this method to clearly differentiate all diamond layers on any one of the sample substrates investigated. These findings could justify a future application of both CL microscopy and CL microspectr ophotometry in production control.