A local structural investigation has been carried out on the 10 Aring; InAsxP1minus;xlayer inadhocgrown InAsxP1minus;x/InP epitaxial multistructures deposited by low pressure metallorganic chemical vapor deposition by means of extended xhyphen;ray absorption fine structure spectroscopy, high resolution transmission electron microscopy, and high resolution xhyphen;ray diffraction analyses. The goal was to characterize the local structure of the unwanted, strained, interface layers of InAsxP1minus;xproduced by the exposure of the InP surface to AsH3as occurs during the growth of InP/In0.53Ga0.47As heterostructures optimized for photonics. High resolution xhyphen;ray diffraction and high resolution transmission electron microscopy confirm the high crystalline perfection of the investigated interfaces. As Khyphen;edge extended xhyphen;ray absorption fine structure analysis shows, the first shell environment of As at these interfaces is similar to that found in bulk InAsxP1minus;xalloys of similar composition, as determined experimentally and by comparison with recent theories of bond lengths in semiconductor alloys. In particular we measure an Asmdash;In bond length which varies at most 0.02 Aring; with As concentration at the interface; this implies that epitaxy with InP is accompanied by local structural distortions, such as bond angle variations, which accommodate the nearly constant Asmdash;In bond length.
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