Dislocation Generation Mechanisms and Layer Growth in InP Epitaxy as a Function of Growth Conditions

By studying InP epitaxies it has been found that optimum growth conditions are not achieved under low growth rate regimes, which, on the contrary, yield a defect density nearly as high as under high growth rate conditions, due to the creation of a very high density of point defects from which dislocation loops originate. Such loops are generated not only at the substrate-epilayer interface but also throughout the layer and depend on the supersaturation of the feeding phases. Under conditions yielding high dislocation density both layer and hillock growth mainly occur by spiral growth.