Photoacoustic investigations of optical absorption, photoluminescence, and thermal diffusivity of Porous Diamond-Like-Carbon films

摘要

Porous diamond-like-carbon (PDLC) has been investigated by photoacoustic spectroscopy (PAS) and photoluminescence (PL). From optical absorption data we have observed broad spectra distributions, spanning the wavelength interval, 350-850 nm, corresponding to phonon energies from 1.46 to 3.54 eV. For photoluminescence we have found a bright intensity around 360 nm. The complex energy transitions found have also been observed in porous silicon (PS) with much discussion. The amplitude and phase of the PA signals were measured at different frequencies of modulation in order to obtain the thermal diffusivity coefficient and has been obtained a value, which is about half of the crystalline silicon.