High Resolution X-Ray Diffraction in-situ study of very small complexes: the case of hydrogenated dilute nitrides

In this work it is demonstrated how in-situ high resolution x-ray diffraction (HRXRD), performed during thermal annealing with a conventional laboratory source, can be used in a spectroscopic approach in order to get information on the evolution kinetics of very small complexes formed in an epitaxial layer. HRXRD measurements collected with different annealing strategies (by linear temperature ramp and isothermal annealings) allow measuring the lattice parameter of the layer (i.e. the layer strain) and, by using a proper modeling, the dissolution energy spectrum of the complexes can be extracted. The underlying idea is that each type of complexes present in the layer gives a specific lattice strain which changes under annealing, allowing to accurately trace the complex evolution. As an example, in the present work this new methodology is applied to the study of N-H complexes formed in H-irradiated GaAs1-xNx/GaAs layers.