IUCr journals

Compositional depth profiling of polycrystalline thin films by grazing-incidence X-ray diffraction

J. Appl. Cryst. (2006). 39, 683–696 [doi.org/10.1107/S002188980601987X]

[Graph 1](Top) Measured (dots) and simulated (solid lines) diffraction profiles of the 112 reflection of a Cu(In,Ga)(S,Se)2 thin film; (bottom) Corresponding optimized S/(S+Se) depth profile in comparison to a profile obtained by secondary ion mass spectroscopy (SIMS).
A novel pattern matching method for compositional depth profiling of polycrystalline thin films using grazing incidence X-ray diffraction (GIXRD) is proposed. A layer absorption model permits generation of GIXRD patterns on the basis of instrument function, compositional depth profiles and absorption characteristics. In contrast to other methods the modelling approach exploits the information stored in the shape evolution of the peak profile as a function of incidence angle. As an example the Cu and S depth gradients in a 2 μm thick Cu(In,Ga)(S,Se)2 thin film are accurately refined.

I.M. Kötschau and H.W. Schock