Abstract
Epitaxial CrGe was grown locally on both (111) and (001) Ge by a solid-phase epitaxy scheme. Both plan-view and cross-sectional transmission electron microscopy were applied to determine the orientation relationships between epitaxial CrGe and germanium substrates, and to characterize the microstructural features of epitaxial regions and CrGe/Ge interfaces. The best CrGe epitaxy was obtained in (111) samples annealed first at 250°C for 1 h followed by heat treatment at 600°C for 1 h. Epitaxial regions as large as 20 μm in size were observed. CrGe was the first refractory germanide grown epitaxially on germanium. The quality of epitaxy is also unsurpassed by any metal germanide epitaxy achieved to date. The growth of a number of epitaxial germanides on germanium with regular atomic arrangements at the interfaces may facilitate the basic understanding of metal-semiconductor interactions as well as enhance the performance of various semiconductor-based devices.