Decomposition mechanisms of thin palladium acetate film with excimer UV radiation

Pre-nucleation of surfaces with palladium from thin palladium acetate films on a range of substrate materials by UV-induced decomposition is described. The optical transmission of the films after irradiation with incoherent UV radiation from several excimer lamp sources provided information about the deposition rate at different UV intensities and exposure times using three different wavelengths: λ = 172 nm (Xe2∗), λ = 222 nm (KrCl∗), and λ = 308 nm (XeCl∗). The gaseous products produced during UV exposure were measured using mass spectrometry (MS). The decomposed products such as H2O, CO2, +CCH3, +COCH3 and +CH3 were observed. The decomposition mechanism of palladium acetate is discussed and a simple model calculation describing photolytic decomposition processes in the thin palladium acetate films is presented. Results will be compared to those obtained by laser and thermal decomposition of palladium acetate. The deposited palladium can act as an activator for subsequent patterned chemical metal deposition techniques in which micrometer thick copper, nickel, or gold layers with good electrical resistivity are applied.