Skew asymmetric arrangement of X-ray diffraction for structural diagnostics of multi-layer semiconductor materials
|Zbigniew Świątek 1, Igor M. Fodchuk 2, Elżbieta Bielańska 1, Marek S. Michalec 3|
1. Polish Academy of Sciences, Institute of Metallurgy and Materials Sciences (IMIM PAN), Reymonta 25, Kraków 30-059, Poland
Progress in fabrication of the optoelectronic devices based on epitaxial thin-films and semiconductor multilayer structures, requires an improvements of techniques used for the material characterization.
The method in a skew asymmetric arrangement of X-ray diffraction in Bragg geometry for a structural diagnostic of defected and multi-layers semiconductor materials is presented. New possibilities of this method for a layer-by-layer visualization of structural changes in subsurface crystal layers are demonstrated for semiconductor materials after various types of surface treatments such as a chemical etching, laser irradiation and ion implantation.
The lattice strain and structural changes in materials produced by existing and introduced defects ware characterized by a combination of X-ray topography and diffraction techniques using single- and double-crystal configurations in the symmetric, asymmetric and skew-asymmetric geometries. Finally, to visualise of microstructural changes and to compare with their theoretical models, X-ray structural investigation was accompanied by transmission electron microscopy, scanning electron microscopy, atomic force microscopy and secondary ion mass spectroscopy measurements.
To build a full possible picture of microstructure of such materials, the simulation and interpretation of diffraction reflection curves of crystalline structures with a heterogeneous near-surface layer have been performed on the basis of a kinematics diffraction theory, analytical solutions of the Takagi-Topan equations in semi-kinematics approximation and generalized dynamic theory of X-ray scattering. Moreover, additional simulations of processes of defects generation in model materials caused by an ion implantation and dopant diffusion were carried out.
The presented method in this skew-asymmetrical mode is both a recommendable and useful tool for studying epitaxial thin films as well as multi-layer systems.
Presentation: Poster at E-MRS Fall Meeting 2007, Symposium H, by Marek S. Michalec
See On-line Journal of E-MRS Fall Meeting 2007
Submitted: 2007-05-21 12:14 Revised: 2009-06-07 00:44