In-situ laser interference patterning of MBE growth surfaces

Single-pulse laser interference is applied to a Molecular Beam Epitaxy growth chamber to achieve in-situ patterning during the growth of III-V materials, with a focus on producing arrays of III-V quantum dots. We will describe the construction and characterization of the interference system as well as the in-situ patterning results. Pulsed laser interference is shown to strongly interact with the growing surface to produce periodic nanoscale features such as holes and islands, the nature of which is dependent on the local surface energy distribution. We describe a mechanism for the formation of these features in terms of surface diffusion under the influence of the periodic thermal gradient induced by the interference pattern. Nanoislands formed at the interference minima are shown to be ideal sites for quantum dot nucleation.