Determination of thermal conductivity of CVD diamond films via photoacoustic measurements

A novel method of determination of polycrystalline diamond films' thermocon ductive properties using the photoacoustic effect is proposed. By this meth od, we studied the diamond films grown on silicon substrates using chemical vapor deposition technique. A value of thermal conductivity obtained for t he films was less than half that for diamond single crystal. The decrease o f thermal conductivity, as well as characteristic features of optical prope rties of the films, is explained by the presence of a large amount of inter crystallite boundaries and other structure defects and admixures detected u sing Raman and photoluminescent spectroscopies.