RECIPROCAL SPACE MAPPING ON SI1-XCX EPILAYERS AND SI-N C/SI-N SUPERLATTICES/

High-resolution X-ray diffraction (HRXRD) and triple-axis diffrac tome try (TAD) are used to investigate Si1-xCx epilayers and Si-n/C/Si-n su perlattices. The samples were annealed in several steps to obtain info rmation about their thermal stability. During annealing defects are fo rmed in the epitaxial layers as well as in the substrates, leading to a contribution of diffusely scattered intensity around the particular reciprocal lattice points. A comparison of the measured intensity dist ribution in reciprocal space with model calculations based on a theory by Krivoglaz shows that the defects in the layers are different from those in the substrates, and that the assumption of small spherical de fects in the epilayers leads to a quite good agreement between measure ment and simulation. The comparison of different samples also shows th at the formation of the defects depends on the particular sample struc ture.