Epitaxial Ge films have been grown on Ge(111) and GaAs(111) surfaces using remote plasma enhanced chemical vapor deposition. Prior to growth, all substrates were subjected to an in situ hydrogen plasma treatment to remove surface oxides. The effect of deposition temperature on the epitaxial quality has been studied using reflection high-energy electron diffraction, Rutherford backscattering/channeling spectrometry, and transmission electron microscopy. Reflection high-energy electron diffraction patterns show fundamental streaks on all deposited layers and fractional order streaks on layers grown between 300 and 400 °C. Rutherford backscattering/channeling analysis shows severe degradation in crystalline quality below 300 ° C. Currently, the lowest channeling yields have been for Ge/Ge(111) grown at 350 °C (χmin =4%) and Ge/GaAs(111) grown at 300 °C (χmin =8%). Transmission electron microscopy indicates that the predominant defects in these films are inclusions and microtwins, respectively. The possible origin of these defects is discussed.