Microscopic bending of GaAs layers grown by epitaxial lateral overgrowth

X-ray diffraction has been used to study the influence of the mask material on properties of GaAs layers grown by the liquid phase epitaxial lateral o vergrowth (ELO) on (100) GaAs substrates. We show that ELO stripes bend tow ards the SiO2 mask in the direction perpendicular to seeding lines in a sim ilar way to that as studied recently by x-ray topography for Si lamellae [H . Raidt, R. Kohler, F. Banhart, B. Jenichen, A. Gutjahr, M. Konuma, I. Sili er, and E. Bauser, J. Appl. Phys. 80, 4101 (1996)]. The bending disappears when the mask is removed by selective etching. This microscopic bending is reduced by nearly 2 orders of magnitude when graphite instead of SiO2 is us ed to mask the substrate. (C) 1998 American Institute of Physics. [S0021-89 79(98)01524-2].