MISFIT DISLOCATION MICROSTRUCTURE AND KINETICS FOR INXGA1-XAS INP(100) AND (110) INTERFACES UNDER TENSILE AND COMPRESSIVE STRESS/

Misfit dislocation microstructures and strain relaxation kinetics are studied for 1% lattice mismatched (100) and (110) interfaces under ten sile and compressive stress in the InxGa1-xAs/InP system. Misfit dislo cations are observed to be either 60-degrees a/2[101] total [for (100) compressive and (110) tensile configurations] or 90-degrees a/6[112] partial [dominant for (100) tensile and (110) compressive configuratio ns] types. Relaxation kinetics are observed to be substantially faster for 90-degrees a/6[112] than 60-degrees a/2[101] dislocations. This p roduces significantly different relaxation rates for (100) versus (110 ) interfaces and compressive versus tensile stress. The relaxation is also found to be an extremely strong function of excess stress, with a n increase of about two orders of magnitude of dislocation density per 100 MPa increase in excess stress for interfacial dislocation densiti es in the range 10(2)-10(6) cm-1.