Nanometer-scale GaAs dot structures fabricated using in-situ gas etching technique with InAs dots as mask

We propose a novel method to fabricate nano-meter scale GaAs dot structures by using molecular beam epitaxy and in-situ gas etching using self-assembled nanometer-scale In As dots on GaAs (100) are used as masks. Our method takes advantage of the preferential etching of GaAs and InAs by Cl₂ gas and HCl gas, respectively. The average height and base diameter of resultant GaAs dots are 10 nm and 30 nm, respectively, when measured by atomic force microscopy. These GaAs dots are found to dissociate easily at elevated temperatures, indicating that the overgrowth of a barrier layer must be made at a rather low temperatures.