Reversibility of the island shape, volume and density in Stranski-Krastanow growth

We report on reversible and irreversible phenomena in size-limited InAs island growth (SLIG) on GaAs(001) surface. We found that, with increasing the substrate temperature, the island density of the SLIG islands decreases, the lateral size of the islands increases and the islands strongly flatten. The average volume is either decreased or weakly affected. The total amount of InAs accumulated in quantum dots (QDs) strongly decreases in favour of the gas of In adatoms on the surface. Both unidirectional and reversible tuning of the substrate temperature after formation of the islands causes reversible changes in the island shape and density. We show the possibility of dramatically increasing the volume and the density of QDs approaching the strategically important 1.3 µm wavelength range via adatom condensation with cooling of the substrate after the formation of QDs. We also demonstrate that the substrate temperature cycling procedure may remarkably reduce the defect density in QD structures.

[1]  A. Barabasi,et al.  DISLOCATION-FREE ISLAND FORMATION IN HETEROEPITAXIAL GROWTH : A STUDY AT EQUILIBRIUM , 1997, cond-mat/9710170.

[2]  Piet Demeester,et al.  Low dimensional structures prepared by epitaxial growth or regrowth on patterned substrates , 1995 .

[3]  D. Vanderbilt,et al.  Spontaneous formation of stress domains on crystal surfaces. , 1988, Physical review letters.

[4]  Nikolai N. Ledentsov,et al.  Ordered arrays of quantum dots: Formation, electronic spectra, relaxation phenomena, lasing , 1996 .

[5]  Ryoichi Ito,et al.  Surface segregation of In atoms during molecular beam epitaxy and its influence on the energy levels in InGaAs/GaAs quantum wells , 1992 .

[6]  Chen,et al.  Morphological Evolution of Strained Films by Cooperative Nucleation. , 1996, Physical review letters.

[7]  Nikolai N. Ledentsov,et al.  Quantum dot heterostructures , 1999 .

[8]  N. Ledentsov,et al.  Spontaneous ordering of arrays of coherent strained islands. , 1995, Physical review letters.

[9]  A. R. Kovsh,et al.  Optical and structural properties of InAs quantum dots in a GaAs matrix for a spectral range up to 1.7 μm , 1999 .

[10]  M. Scheffler,et al.  Shape and stability of quantum dots , 1997 .

[11]  Dieter Bimberg,et al.  Spontaneous ordering of nanostructures on crystal surfaces , 1999 .

[12]  Nobuhiko P. Kobayashi,et al.  In situ, atomic force microscope studies of the evolution of InAs three‐dimensional islands on GaAs(001) , 1996 .

[13]  D. Gerthsen,et al.  Structural and chemical investigation of In 0.6 Ga 0.4 As Stranski-Krastanow layers buried in GaAs by transmission electron microscopy , 2000 .

[14]  D. Vanderbilt.  Phase segregation and work-function variations on metal surfaces: spontaneous formation of periodic domain structures☆ , 1992 .

[15]  Albert-László Barabási,et al.  Self-assembled island formation in heteroepitaxial growth , 1997, cond-mat/9703252.

[16]  Williams,et al.  Shape transition of germanium nanocrystals on a silicon (001) surface from pyramids to domes , 1998, Science.

[17]  A. G. Khachaturi︠a︡n.  Theory of structural transformations in solids , 1983 .

[18]  Lagally,et al.  Size relation for surface systems with long-range interactions. , 1994, Physical review letters.

[19]  M. Lannoo,et al.  Origin of self-assembled quantum dots in highly mismatched heteroepitaxy. , 1995, Physical review letters.

[20]  B. Chakraverty.  Grain size distribution in thin films—1. Conservative systems , 1967 .