Characterization of strain distribution in quantum dots by X-ray diffraction

Structural properties of InAs quantum dots grown on Si (100) substrate have been investigated with G-GIXD reciprocal space mapping. Although both the volume (37 nm in diameter) and the surface coverage (about 11 %) of the InA s dots are small, strong diffraction spots have been observed. To investiga te the origin of the peak broadening, we compared the experimental data wit h structural factors calculated with FEM. We have found that the size of di ffraction spots from the InAs dots is determined not only by their size and within-a-dot strain distribution, but also by the dot-to-dot strain distri bution. (C) 2002 Published by Elsevier Science B.V.