"Optical anisotropies of Si grown on step-graded SiGe(110) layers".

R. E. Balderas-Navarro, L. F. Lastras-Martínez, K. Arimoto, R. Castro-García, O. Villalobos-Aguilar, A. Lastras-Martínez, K. Nakagawa, K. Sawano, Y. Shiraki, N. Usami, and K. Nakajima
Appl. Phys. Lett. 96, 091904 (2010), 2010.


Macroreflectance and microreflectance difference spectroscopies have been used to measure the strain induced optical anisotropies of semiconductor structures comprised of strained Si(110) thin films deposited on top of step-graded SiGe virtual substrates. The stress relaxation mechanism mainly occurs by the introduction of microtwin formation, whose fluctuation depends strongly on growth conditions. Correlations of such optical diagnostics with x-ray diffraction measurements and atomic force microscopy images, allow for the in situ study of the strain within both the top Si layer and the SiGe underneath with an spatial resolution of at least 5 μm.