| Grazing incidence x-ray scattering and angular dependence of x-ray fluorescence techniques using x-rays from synchrotron radiation have been demonstrated as useful tools for probing interface morphology and determination of concentration depth profile in layer-structured materials. Three prototype systems with different growth techniques were prepared for the current study: (i) Si 1-xGex epilayers on Si by molecular beam epitaxy, (ii) CdS/CdTe heterojunctions on glass by radio frequency magnetron sputtering, and (iii) CdS/Cu(In,Ga)Se 2 heterojunctions on glass by chemical bath deposition. In the present study, different methods of data analysis have been worked out to account for the density and composition variations in the systems. In the SiGe epilayers with low roughness, the layer thickness and interfacial roughness as well as the Ge content have been obtained through a simultaneous analysis of both x-ray reflectivity and fluorescence data. In the CdS/CdTe heterojunctions, the x-ray methods have provided a quantitative understanding for the effects of surface roughening and Te migration when the junctions are subjected to thermal annealing at various temperatures. The effects of compositional intermixing and high interfacial roughness in the CdS/Cu(In,Ga)Se2 heterojunctions have been investigated using the x-ray fluorescence technique without the aid of x-ray reflectivity. |
