Abstract
Water vapor has previous been considered to be detrimental to sputtering processes. However, the intentional addition of water vapor during sputter deposition has recently attracted attention as a method to control the structure, as well as physical and chemical properties of metal and oxide thin films. The crystal orientation and surface flatness of metal films, as well as etching rates of conducting oxide films are improved by the addition of water vapor to the sputtering gas. Hydroxide and hydrate thin films, which are electrochemically active, have also been formed using water vapor as a reactive gas. H2O molecules are dissociated into H atoms and OH radicals in the plasma, and these active species are incorporated into the deposited thin films. H2O molecules are also incorporated effectively into the hydrate films at low substrate temperatures, and this has been shown to improve proton conductivity.
