Structure of GaN quantum dots grown under “modified Stranski–Krastanow” conditions on AlN

We propose a procedure to grow GaN quantum dots (QDs) on AlN by using the Ga surfactant effect in plasma-assisted molecular beam epitaxy. Self-formed GaN islands were spontaneously generated under vacuum, after evaporation of the Ga bilayer stabilizing the two-dimensional GaN layer grown under Ga-rich conditions. Island characteristics (size and density) are studied as a function of the nominal amount of GaN deposited. We demonstrate that the QD density can be controlled in the 3×1010 cm−2–2×1011 cm−2 range. It is shown that beyond a given amount of GaN nominally deposited, there is a coexistence between elastic and plastic relaxation, with GaN islands being formed on a partially relaxed two-dimensional GaN layer thicker than two monolayers.

[1]  Christoph Adelmann,et al.  Surfactant effect of gallium during molecular-beam epitaxy of GaN on AlN (0001) , 2001 .

[2]  A. Madhukar,et al.  Onset of incoherency and defect introduction in the initial stages of molecular beam epitaxical growth of highly strained InxGa1−xAs on GaAs(100) , 1990 .

[3]  Reuter,et al.  Surfactants in epitaxial growth. , 1989, Physical review letters.

[4]  Y. Aoyagi,et al.  Optical properties of GaN quantum dots , 2000 .

[5]  Bernard Jusserand,et al.  Structural and optical properties of high quality InAs/GaAs short‐period superlattices grown by migration‐enhanced epitaxy , 1989 .

[6]  N. Moll,et al.  Influence of surface stress on the equilibrium shape of strained quantum dots , 1998 .

[7]  J. M. Moison,et al.  Self‐organized growth of regular nanometer‐scale InAs dots on GaAs , 1994 .

[8]  Jörg Neugebauer,et al.  Structure of GaN(0001): The laterally contracted Ga bilayer model , 2000 .

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

[10]  M. Scheffler,et al.  Adatom kinetics on and below the surface: the existence of a new diffusion channel. , 2003, Physical review letters.

[11]  L. Goldstein,et al.  Growth by molecular beam epitaxy and characterization of InAs/GaAs strained‐layer superlattices , 1985 .

[12]  C. Adelmann,et al.  Strain relaxation in (0001) AlN/GaN heterostructures , 2001 .

[13]  Michael S. Shur,et al.  Elastic strain relaxation and piezoeffect in GaN-AlN, GaN-AlGaN and GaN-InGaN superlattices , 1997 .

[14]  I. Robinson,et al.  Buffer layer strain transfer in AlN/GaN near critical thickness , 1999 .

[15]  Yoshinobu Aoyagi,et al.  Self‐assembling GaN quantum dots on AlxGa1−xN surfaces using a surfactant , 1996 .

[16]  Jin Zou,et al.  STABLE AND METASTABLE INGAAS/GAAS ISLAND SHAPES AND SURFACTANTLIKE SUPPRESSION OF THE WETTING TRANSFORMATION , 1998 .

[17]  Nicolas Grandjean,et al.  From visible to white light emission by GaN quantum dots on Si(111) substrate , 1999 .

[18]  Christoph Adelmann,et al.  Dynamically stable gallium surface coverages during plasma-assisted molecular-beam epitaxy of (0001) GaN , 2002 .

[19]  Savage,et al.  Kinetic pathway in Stranski-Krastanov growth of Ge on Si(001). , 1990, Physical review letters.

[20]  C. Adelmann,et al.  GaN islanding by spontaneous rearrangement of a strained two-dimensional layer on (0001) AlN , 2002 .

[21]  Grandjean,et al.  Delayed relaxation by surfactant action in highly strained III-V semiconductor epitaxial layers. , 1992, Physical review letters.

[22]  W. J. Choyke,et al.  Growth of AlN/GaN layered structures by gas source molecular‐beam epitaxy , 1990 .

[23]  J. Massies,et al.  GaN and AlxGa1−xN molecular beam epitaxy monitored by reflection high-energy electron diffraction , 1997 .

[24]  Reuter,et al.  Influence of surfactants in Ge and Si epitaxy on Si(001). , 1990, Physical review. B, Condensed matter.

[25]  Guy Feuillet,et al.  Growth kinetics and optical properties of self-organized GaN quantum dots , 1998 .

[26]  InP islands on InGaP/GaAs(001): island separation distributions , 1997 .

[27]  Jacobson,et al.  Growth morphology and the equilibrium shape: The role of "surfactants" in Ge/Si island formation. , 1993, Physical review letters.

[28]  J. Gerard,et al.  High quality ultrathin InAs/GaAs quantum wells grown by standard and low‐temperature modulated‐fluxes molecular beam epitaxy , 1988 .

[29]  B. Orr,et al.  Effect of surface tension on the growth mode of highly strained InGaAs on GaAs(100) , 1993 .

[30]  R. Kern,et al.  Elastic relaxation of coherent epitaxial deposits , 1997 .

[31]  J. Brault,et al.  Gallium adsorption on (0001) GaN surfaces , 2003 .

[32]  Nicolas Grandjean,et al.  SURFACTANT MEDIATED EPITAXIAL-GROWTH OF INXGA1-XAS ON GAAS (001) , 1992 .

[33]  Guy Feuillet,et al.  Stranski-Krastanov growth mode during the molecular beam epitaxy of highly strained GaN , 1997 .

[34]  Y. Aoyagi,et al.  The formation of GaN dots on AlxGa1−xN surfaces using Si in gas-source molecular beam epitaxy , 1998 .

[35]  Y. Arakawa,et al.  High-density and size-controlled GaN self-assembled quantum dots grown by metalorganic chemical vapor deposition , 2002 .

[36]  Eaglesham,et al.  Dislocation-free Stranski-Krastanow growth of Ge on Si(100). , 1990, Physical review letters.