Precursors for use in depositing antimony-containing films on substrates such as wafers or other microelectronic device substrates, as well as associated processes of making and using such precursors, and source packages of such precursors. The precursors are useful for deposition of Ge2Sb2Te5 chalcogenide thin films in the manufacture of nonvolatile Phase Change Memory (PCM) or for the manufacturing of thermoelectric devices, by deposition techniques such as chemical vapor deposition (CVD) and atomic layer deposition (ALD).