Lateral periodicity in high-strained (GaIn)As/Ga(PAs) superlattices investigated by X-ray scattering techniques

Yan Zhuang, C. Giannini, L. Tapfer, T. Marschner, W. Stolz

Research output: Contribution to journalArticlepeer-review

Abstract

In this work we investigate the lateral periodicity of symmetrically strained (GaIn)As/GaAs/Ga(PAs)/GaAs superlattices by means of X-ray scattering techniques. The multilayers were grown by metalorganic vapour phase epitaxy on (001)GaAs substrates, which were intentionally off-oriented towards the [011]-direction. The substrate off-oreintation and the strain distribution was found to affect the structural properties of the superlattices inducing the generation of laterally ordered macrosteps. Several high-resolution triple-crystal reciprocal space maps, which were recorded for different azimuth angles in the vicinity of the (004) Bragg diffraction and contour maps of the specular reflected beam collected in the vicinity of the (000) reciprocal lattice point, are reported and discussed. The reciprocal space maps clearly show a two-dimensional periodicity of the X-ray peak intensity distribution which can be ascribed to the superlattice periodicity in the direction of the surface normal and to a lateral periodicity in a crystallographic direction coinciding with the miscut orientation. The distribution and correlation of the vertical as well as of the lateral interface roughness was investigated by specular reflectivity and diffuse scattering measurements. Our results show that the morphology of the roughness is influenced by the off-orientation angle and can be described by a 2-dimensional waviness.
Original languageAmerican English
Pages (from-to)377–383
JournalIl Nuovo Cimento D
DOIs
StatePublished - Feb 1997
Externally publishedYes

Keywords

  • As/Ga
  • Superlattices
  • X-ray diffraction

Disciplines

  • Electrical and Computer Engineering

Cite this