INTERFERENCE EFFECTS IN X-RAY DOUBLE-CRYSTAL ROCKING CURVES OF GEXSI1-X SI SUPERLATTICES/

Interference effects in the x-ray double-crystal rocking curves of Gex Si1-x/Si strained-layer superlattices have been simulated based on the x-ray dynamical scattering theory. We found that the A1BA2 type of st ructure due to unstable growth conditions causes a series of strong os cillation fringes beside the superlattice reflection satellite peaks. The positions and intensities of these oscillation fringes with respec t to the superlattice satellite peaks are strongly correlated to the n umber of periods in the subsuperlattice layer B and the relative mean lattice mismatch between A and B with respect to the substrate.