Strain, size, and composition of InAs quantum sticks embedded in InP determined via grazing incidence x-ray anomalous diffraction.

Abstract

We have used x-ray anomalous diffraction to recover the model-independent Fourier transform (x-ray structure factor) of InAs quantum sticklike islands embedded in InP. The average height of the quantum sticks, as deduced from the width of the structure factor profile, is 2.54 nm. The InAs out-of-plane deformation, relative to InP, is 6.1%. Diffraction anomalous fine structure provides evidence of pure InAs quantum sticks. Finite difference method calculations reproduce well the diffraction data, and give the strain along the growth direction. The chemical mixing at interfaces is also analyzed.