Guided quantum dot ordering by self-organized anisotropic strain engineering and step engineering on shallow-patterned substrates

Formation of linear InAs/InGaAsP/InP (100) quantum dot arrays by self-organized anisotropic strain engineering in chemical beam epitaxy

“…At MBE 2006 we have reported our concept of lateral QD ordering based on self-organized anisotropic strain engineering for the InAs/GaAs material system using molecular beam epitaxy [2]. Here we demonstrate the formation of laterally ordered linear InAs QD arrays by self-organized anisotropic strain engineering of an InAs/InGaAsP superlattice (SL) template on InP (1 0 0) substrate in chemical beam epitaxy (CBE).…”

Deterministic self‐organization: Ordered positioning of InAs quantum dots by self‐organized anisotropic strain engineering on patterned GaAs (311)B

“…In our previous study we have introduced the concept of complex, lateral ordering of InGaAs and InAs QDs based on guided self-organized anisotropic strain engineering of InGaAs/GaAs superlattice (SL) templates grown on artificially patterned GaAs (311)B substrates. The steps and facets generated on the surface of shallow-and deepetched substrates guide the self organization process during SL template formation to produce more complex QD ordering such as periodic stripes and linear groups as well as QD-free regions [3].…”

“…The PL was dispersed by a single monochromator and recorded by a cooled InGaAs linear array detector.. Figure 1 shows the (a) InGaAs QDs, (b) InAs QD molecules, and (c) InAs single QDs, grown on planar GaAs (311)B substrates. Well-ordered periodic arrangements of connected InGaAs QD arrays, isolated InAs QD molecules, and single InAs QDs are formed on the SL template due to the two-dimensional strain field modulation generated by anisotropic adatom surface migration (due to annealing) and laterally and vertically strain correlated growth (due to stacking) during SL template formation, as discussed in detail in [3][4][5]. The single QDs are obtained at increased temperatures for SL template and InAs QD growth, and decreased InAs amount plus annealing for 30 s. The high growth temperature enhances the strain driven In adatom surface migration to produce more distinct lateral strain field modulations with smaller nodes during SL template formation followed by QD coalescence during annealing after InAs deposition into single QDs.…”

Complex laterally ordered InGaAs and InAs quantum dots by guided self-organized anisotropic strain engineering on shallow- and deep-patterned GaAs (311)B substrates

“…The monolayer-height steps generated on the shallow-patterned substrates with pattern sizes of micrometer length scales modify the SL template formation to form wellpositioned bends and branches of linear QD arrays on GaAs ͑100͒ and transform the spotlike InGaAs QD arrangement on GaAs ͑311͒B into a characteristic zigzag arrangement. 9,10 The pattern sizes are clearly larger than adatom surface migration lengths ͑ഛ1 m͒ and strain field decay lengths ͑sev-eral 10 nm͒ governing the self-organization process. Hence, guided self-organization is introduced for the lateral ordering of QDs in complex architectures to create the building blocks for future quantum functional devices.…”