Structural characterization of ingaas/inp heterostructures grown under compressive and tensile stress

A systematic study of strain relaxation mechanisms by TEM, XRD, RBS-channelling, SEM-CL and AFM in InxGa1-xAs/InP heterostructures grown by MOCVD under tensile and compressive initial misfit is reported. It is found that the layers under compression (0.61 directions. The residual strain vs. the layer thickness follows the same law experimentally determined for compressive MBE-grown InxGa1-xAs/GaAs(x<0.2) specimens showing no composition, growth technique or temperature effect. The tensile layers (0.2 directions as soon as a measurable strain relaxation appears. A possible correlation between grooves, planar defects and the mechanism of strain release is discussed.