Fabrications of GaAs quantum dots by modified droplet epitaxy

We propose a modified droplet epitaxy method for fabricating self-organized GaAS/AlGaAs quantum dots (QDs) with a high As flux irradiation and a low s ubstrate temperature. By our novel method, GaAs QDs were successfully forme d, retaining their pyramidal shape; original base size and density of dropl ets, and preventing layer-by-layer growth. Quantum size effects of the QDs were distinctly observed by photoluminescence measurements. It was confirme d that this new modified droplet epitaxy method is promising for fabricatin g a high-quality GaAs/AlGaAs QD system.