Sinusoidally modulated superlattices: Fabrication and structural studies

Semiconductor “sinusoidal superlattices” of (Formula presented)—that is, periodic structures in which the chemical composition parametrized by x varies sinusoidally along one direction—were fabricated by rotating a substrate through an inhomogeneous distribution of constituent fluxes within a molecular beam epitaxy growth chamber. The modulation of chemical composition x is accompanied by modulation of strain, owing to the difference in Zn-Se and Zn-Te bond lengths. By fitting x-ray diffraction scans around the (002), (004), and (006) Bragg reflections for (001)-oriented (Formula presented) sinusoidal superlattices to a simple scattering theory, we have determined both the strain and the chemical modulation amplitudes in these structures.