Growth and annealing of InAs quantum dots on pre-structured GaAs substrates

In this study, we investigated the effect of in situ annealing on InAs quantum dots site-selectively grown on pre-structured GaAs substrates. A morphological transition is observed with original double dots merging into one single dot during annealing. This is accompanied by a reduction of quantum dots originally nucleating between defined sites. The photoluminescence intensity of annealed site-selective quantum dots is compared to annealed self-assembled dots with linewidths of single dot emission of about 170 and 81 μeV, respectively. UV-ozone cleaning is used to optimize the sample cleaning prior to quantum dot growth.

[1]  G. Eisenstein,et al.  Site-controlled InAs quantum dots grown on a 55 nm thick GaAs buffer layer , 2009 .

[2]  Nikolai N. Ledentsov,et al.  Reversibility of the island shape, volume and density in Stranski-Krastanow growth , 2001 .

[3]  M Henini Handbook of Compound Semiconductors , 2000 .

[4]  D. Ritchie,et al.  Site control of InAs quantum dot nucleation by ex situ electron-beam lithographic patterning of GaAs substrates , 2006 .

[5]  O. Schmidt Lateral alignment of epitaxial quantum dots , 2007 .

[6]  Leonard,et al.  Critical layer thickness for self-assembled InAs islands on GaAs. , 1994, Physical review. B, Condensed matter.

[7]  P. Petroff,et al.  A quantum dot single-photon turnstile device. , 2000, Science.

[8]  D. Schaadt,et al.  Morphology and stress evolution of InAs QD grown and annealed in-situ at high temperature , 2010 .

[9]  C. Heyn Stability of InAs quantum dots , 2002 .

[10]  So,et al.  Assembling strained InAs islands on patterned GaAs substrates with chemical beam epitaxy , 1996 .

[11]  Alfred Forchel,et al.  Temperature dependence of the exciton homogeneous linewidth in In 0.60 Ga 0.40 As/GaAs self-assembled quantum dots , 2002 .

[12]  Weidong Yang,et al.  Formation of InAs/GaAs quantum dots by molecular beam epitaxy: Reversibility of the islanding transition , 1997 .

[13]  S. Ingrey 5 – Surface Processing of III-V Semiconductors , 1995 .

[14]  Silke Christiansen,et al.  Self-assembled semiconductor nanostructures: Climbing up the ladder of order , 2002 .

[15]  R. Koch,et al.  Stress evolution during growth of bilayer self-assembled InAs/GaAs quantum dots , 2006 .

[16]  M. Kamp,et al.  Single site-controlled In(Ga)As/GaAs quantum dots: growth, properties and device integration , 2009, Nanotechnology.

[17]  B. Gerardot,et al.  Entangled photon pairs from semiconductor quantum dots. , 2005, Physical Review Letters.

[18]  O. Schmidt,et al.  Site-controlled growth and luminescence of InAs quantum dots using in situ Ga-assisted deoxidation of patterned substrates , 2008 .

[19]  K. Ploog,et al.  Stress development during annealing of self-assembled InAs/GaAs quantum dots measured in situ with a cantilever beam setup , 2006 .

[20]  David A. Ritchie,et al.  Formation and ordering of epitaxial quantum dots , 2008 .