Growth Interruption Effect on the Fabrication of GaAs Concentric Multiple Rings by Droplet Epitaxy
1 L-NESS and Dipartimento di Scienza dei Materiali, Universita’ di Milano Bicocca, Via Cozzi 53, 20125, Milan, Italy
2 CNISM, L-NESS and Dipartimento di Fisica, Politecnico di Milano, Via Anzani 42, 22100, Como, Italy
Nanoscale Research Letters 2010, 5:1897-1900 doi:10.1007/s11671-010-9752-5Published: 21 August 2010
We present the molecular beam epitaxy fabrication and optical properties of complex GaAs nanostructures by droplet epitaxy: concentric triple quantum rings. A significant difference was found between the volumes of the original droplets and the final GaAs structures. By means of atomic force microscopy and photoluminescence spectroscopy, we found that a thin GaAs quantum well-like layer is developed all over the substrate during the growth interruption times, caused by the migration of Ga in a low As background.