Sharp contrast of the density and size of Ga metal droplets on photolithographically patterned GaAs (100) by droplet epitaxy under an identical growth environment

A sharp contrast of the density and size of Ga metal droplets (MDs) on strip patterned GaAs (100) is demonstrated through droplet epitaxy (DE) and photolithography technique. As clearly evidenced by scanning electronic microscope (SEM) and atomic force microscope (AFM), MD density between etched (patterned) and un-etched (un-patterned) surfaces can be sharply different up to one order of magnitude under an identical growth condition. Etched surface exhibits much higher density and smaller diameter and height of MDs.