One-dimensional germanium nanostructures with different morphologies, sizes, and microstructures were synthesized in a small-diameter quartz cavity by evaporation of Ge powders. The substrate temperature was observed to be a vital factor for controlling the morphologies of Ge structures, such as nanochains, nanowires, microspheres-string nanowires, and microrods. High-resolution electron microscopy revealed that the nanochains and nanowires grew along [1 1 1] direction, whereas the microspheres and microrods were polycrystalline. The growth mechanisms of these as-synthesized Ge nanostructures were also investigated. (C) 2010 Elsevier B.V. All rights reserved.