Abstract
Correlation photoacoustic spectroscopy was carried out in X-ray region using synchrotron radiation(SR) as an exciting source. Thermal diffusion in copper foils and in laminated samples was investigated. The characteristic rise and fall times of correlation spectra, τ0 and τf, respectively, were found to be influenced by sample thickness with the maximum values at intermediate thicknesses (10 and 50μm) for copper samples. This was interpreted as arising from the competing effect between the thermal diffusion within the sample and the thermal radiation from the sample surface. For the laminated samples, increases of τ0 and τf were observed with the increase of thickness of polymer layer on the copper substrate.
