Effects of hydrogenation on the local structure of In{sub x}Ga{sub 1-x}As{sub 1-y}N{sub y} quantum wells and GaAs{sub 1-y}N{sub y} epilayers

We address in this paper the issue of the effects of hydrogenation on the local structure of In{sub x}Ga{sub 1-x}As{sub 1-y}N{sub y} quantum wells by combining In K-edge x-ray absorption and Ga K-edge x-ray diffraction anomalous fine structure experiments. We found that the cation-As bond lengths in hydrogenated samples are systematically longer than the values predicted by a valence force field model corrected for the epitaxial strain. We interpret this bond lengths stretching as a local effect of the formation of N-H complexes very recently predicted by theoretical calculations. By analyzing the Debye-Waller factor of the Ga-As bond length distribution, we observed that hydrogenation removes the static disorder induced by N incorporation in GaAs; this effect is due to the unique characteristics of the N substitutional anion and to the breaking of the ionic Ga-N bonds upon hydrogenation.