ANALYSIS OF EPITAXIAL GAXIN1-XAS/INP AND ALYIN1-YAS/INP INTERFACE REGION BY HIGH-RESOLUTION X-RAY-DIFFRACTION

A detailed strain analysis of high resolution x-ray diffraction patterns taken from GaxIn1-xAs and AlyIn1-yAs layers grown lattice matched on (001) InP substrates shows the existence of distinct interface regions. Our dynamical diffraction model allows us to detect buried interface layers with submonolayer resolution and differences in composition of less than 1% from the rest of the epilayer. Comparison between experimental and theoretical rocking curves reveals that the interface region between epilayer and substrate comprises 2 monolayers InAs plus GaxIn1-xAs (or AlyIn1-yAs) interlayer with different group III element ratios.