The defect structure of MBE-grown (100) InGaAs/GaAs mismatched hetero-epitaxial layers was studied by selective electrochemical (anodic) etching. By incremental layer removal, the depth profile of the etch-pit density was mapped. The defect density was inversely proportional to the layer thickness, and increased with In content. The results were explained by a quantitative theoretical model of threading dislocation annihilation. The importance of the layer residual strain in the annihilation process was shown.

Interpretation of the Depth-Dependent Etch Pit Density in InGaAs/GaAs Heterostructures. Á.Nemcsics, F.Riesz: Physica Status Solidi C, 2003, 0[3], 893-6