Effects of GaAs-spacer strain on vertical ordering of stacked InAs quantum dots in a GaAs matrix

Characterization of Structure and Composition of Quantum Dots by Transmission Electron Microscopy

“…But the diffraction contrast was simulated for the cross-sectional orientation, allowing one to discuss the depth dependency of the contrast of the pyramids and the possibilities and limitations of the size and shape analyses, bestowing great caution on interpreting the images. Not reflecting these results, in different papers [8,[37][38][39][40][41][42][43][44][45][46] the same caution is demanded and the necessity is demonstrated of suitable model and image simulations. Thus, in the following, MD simulations and static relaxations mainly of InGaAs QDs in a GaAs matrix are discussed to gain a better understanding of the structural modifications due to relaxation and of the resulting TEM and HREM contrast modifications.…”

“…The importance to investigate such configurations has at least two reasons. First, small embedded precipitates have always facets; a transition between dome-like structure and pyramids, e.g., due to changes in spacer distance, change the number and arrangement of the facets, and thus strain and electronic properties [23,39,45,46,69]. Second, for highly facetted structures the continuum elasticity is practically inapplicable and FEM calculations must be done in 3D instead of 2D [42][43][44][45][46]69].…”

Stacking number dependence of size distribution of vertically stacked InAs/GaAs quantum dots

“…[10][11][12] Therefore, the drastic decrease of the QD size distribution with increasing the stacking number from 1 to 2 (Fig. 5) is supposed to result from the strain field induced by the embedded InAs QDs.…”

Formation and stacked layer of quantum dots

“…The results are summarized in Fig. 8 [42] which shows the effect of GaAs thickness and dot size on the vertical ordering of InAs QDs.…”