IMPLEMENTATION OF LARGE-SCALE DEPOSITION OF DIAMOND FILMS BY COMBUSTION SYNTHESIS

In the era of rapid advancement in the technology of low-temperature and low-pressure diamond film deposition, the process of combustion synthesis has attracted great attention as a result of its high deposition rate, simplicity of operation, and system flexibility. From the practical point of view, combustion synthesis has great potential to become the process of choice for large-scale, wear-resistant diamond coatings. To achieve such goals, however, the problem of radial non-uniformity in film quality resulting from the complex flame structure has first to be solved. In this study, a large-scale, continuous, high-quality diamond film was deposited onto silicon substrates with a prototype combustion deposition system. It was found that the surface pretreatment in addition to the carburizing treatment, and the regulation of the flame structure during the process, were the two most important factors in controlling the deposition rate and film quality. Application of the sheathed-flame design results in a dramatic enhancement in deposition area and film quality. Together with the modification of a scanning mechanism, combustion synthesis has been proven to be capable of large-scale and high-quality deposition of diamond films.