Pulsed laser surface modifications of diamond thin films

In view of practical applications requiring diamond films, plates and membr anes with very smooth surfaces, ArF excimer laser polishing treatments were applied to thin (30 mu m) diamond films grown by CVD on silicon substrates . The as-prepared diamond surfaces and the laser-treated parts of the sampl es were characterised by SEM analysis, Raman and micro-Raman spectroscopy. The presence on the laser-treated surface of a thin amorphous carbon layer responsible for the higher surface electrical conductivity and for the diff erent optical reflectivity properties was evidenced. Using confocal micro-R aman spectroscopy a comparative depth profile analysis of the phase quality , below the surface in different regions of the films, was carried out. Aft er short (10 min) treatment by H-2 plasma etching in the CVD chamber the gr aphitic top layer was completely removed from the samples. (C) 1999 Elsevie r Science S.A. All rights reserved.