Analysis of X-ray diffraction curves of trapezoidal Si nanowires with a strain distribution

X-ray diffraction curves of oxidized Si nanowires with a strain distribution having a trapezoidal cross-section are analyzed using an X-ray kinematical treatment. The analysis is carried out assuming a strain distribution and cross-sectional shape to calculate a diffraction curve, followed by comparing it to the experimental one. The calculated diffraction curves reproduce the experimental ones over the whole measured range. Particularly, the calculated intensities as well as positions of fringe maxima and minima agree with the experimental curves. Also, the calculation indicates that the strain on a plane parallel to the bases becomes larger, as the plane becomes far from the longer base. This is demonstrated only by calculating X-ray diffraction curves assuming both strain distributions and cross-sectional shapes.