Abstract: A supply of a germanium precursor such as germanium n-butylamidinate is provided in close proximity to a microelectronic device substrate to be contacted therewith for deposition of germanium-containing material on the substrate. Specific arrangements are described, including tray and reservoir structures from which solid, liquid, suspended or dissolved germanium precursor can be volatilized for transport to the substrate surface together with other precursors, carrier gases, co-reactants or the like. In such manner, the germanium precursor can be activated independently of the activation of other precursors, within the deposition chamber, to achieve highly efficient formation of germanium-containing material on the substrate, e.g., a GST film of a phase change memory device.