Low density InAs quantum dots with control in energy emission and top surface location

In this work we extend the droplet epitaxy growth technique to the fabrication of low density InAs quantum dots (QDs) on GaAs (001) substrates with control in size, energy emission, and top surface location. In particular, depending on the amount of InAs material deposited, it has been possible to tune the QD energy emission over a range of 1.12–1.40 eV while keeping constant the nanostructures density at 2×108 cm−2. Moreover, the capping growth process of these QD shows mounding features that permit their spatial identification once embedded by a GaAs capping layer.
The authors acknowledge the financial support by Spanish MEC and CAM through Project Nos. TEC-2005-05781- C03-01/-03 and NAN2004-09109-C04-01/-03, by Consolider Grant No. QOIT CSD2006-0019 and S-505/ESP/ 000200.