STRUCTURAL-PROPERTIES OF GAAS GE HETEROSTRUCTURES AS A FUNCTION OF GROWTH-CONDITIONS/

The structural properties of atmospheric pressure, metal organic vapou r phase epitaxy grown GaAs/Ge heterostructures were investigated by tr ansmission electron microscopy and high-resolution X-ray diffraction a s a function of substrate misorientation, V to III ratio, growth rate and temperature. A 3 degrees misorientation of the substrate is effect ive in suppressing the antiphase domains, but only in optimized growth th conditions. In the ranges considered, the strain release is influe nced more by the misorientation angle and the V to III ratio than by t he substrate temperature and the growth rate. The great majority of mi sfit dislocations are 60 degrees in character; occasionally they react to form edge segments. The misfit dislocations strongly interact with the antiphase boundaries. The contribution of the antiphase domains t o strain relaxation is discussed.