The nucleation and initial growth of gold films deposited onto sodium chloride by ion-beam sputtering

Data are presented for the initial growth of sputtered films of gold on vacuum-cleaved rocksalt substrates. The films were grown in high vacuum by means of an ion-beam sputtering system, so that no plasma effects were present.The experimental variations of island density with such parameters as deposition time, substrate temperature and deposition rate are reported. These results have been compared with existing data for evaporated films and differences have been found.A simplified treatment of the nucleation and growth kinetics has been used to correlate the results by sputtering to those by evaporation. In the case of sputtering, it has been necessary to postulate a constant density of preferred adsorption sites on the substrate. More detailed theories have been used to confirm the analysis.Apart from the influence of the preferred sites, growth apparently proceeds in the same way for deposition by sputtering and for deposition by evaporation.