BREAKING UP OF MISFIT DISLOCATIONS IN GAASIN0.3GA0.7AS GAAS HETEROSTRUCTURE/

The effect of GaAs cap layer with different thicknesses in the GaAs/In 0.3Ga0.7As/GaAs heterostructure on misfit dislocation is investigated with transmission electron microscopy, and it is found that lines of m isfit dislocation break up and move out of the structure when the GaAs cap layer thickness exceeds a certain amount. The breaking up and mov ing out of misfit dislocations, initially confined in the (001) substr ate/InGaAs epilayer interface, occur mainly along the [110] direction on the interface in the structure. (C) 1995 American Institute of Phys ics.