In:
Zeitschrift für Kristallographie - Crystalline Materials, Walter de Gruyter GmbH, Vol. 219, No. 4 ( 2004-4-1), p. 195-200
Abstract:
For the design flexibility of SiGe based quantum cascade lasers high Ge composition Si/SiGe ( x = 80%) superlattices are important. We present an X-ray small angle scattering and high-resolution X-ray diffraction study on strain compensated Si/Si 1– x Ge x multiple quantum well structures with Ge compositions ( x up to 80%), grown on Si 0.5 Ge 0.5 pseudo-substrates. To test the temperature stability of such layers occurring in processing steps, in-situ annealing X-ray reflectivity measurements were performed for temperatures up to 810 °C. From the analysis of the reflectivity data, we obtain the layer thicknesses and the interface roughness of the superlattices during annealing. Using a one dimensional diffusion equation, the Ge diffusion coefficient for these conditions was obtained. Furthermore, the strain status and Ge composition in the superlattice structure and in the SiGe buffer before and after annealing were determined from the symmetrical and asymmetrical reciprocal space maps.
Type of Medium:
Online Resource
ISSN:
2196-7105
,
2194-4946
DOI:
10.1524/zkri.219.4.195.30440
Language:
English
Publisher:
Walter de Gruyter GmbH
Publication Date:
2004
SSG:
13
Bookmarklink