PUB - Publikationen an der Universität Bielefeld

With the aim of providing a more detailed understanding of the reaction mechanism in the combustion chemical vapor deposition (CVD) of diamond, two flame CVD systems were investigated. In an acetylene-oxygen flame at ambient pressure, the influences of important deposition parameters including stoichiometry, substrate temperature and pretreatment as well as the effect of gas phase additives were studied systematically, and conditions for controlled diamond growth were defined. From a large number of deposition experiments, film and growth properties such as growth rate, morphology, stress and purity were thus linked to the global gas phase composition. In a low-pressure CVD flame, gas phase constituents including important intermediates were analyzed in situ under selected deposition conditions to provide further insight into the reaction mechanism. For this, a combination of molecular beam sampling mass spectrometry (MBMS) and laser spectroscopy was employed. The species profiles obtained from these experiments were compared with simulation results of the flame chemistry.