Molecular beam epitaxial growth of ordered GaAs nanodot arrays using anodic alumina masks

Fabrication of highly ordered nanodot arrays of dot size down to tens of nanometers has attracted intensive studies in recent years. Of the various fabrication methods, self-assembled growth based on strain (Stranski-Kranstanov (SK)) has been the choice for the InAs/GaAs system. This mode however, typically results in random location of dots and broad size distribution. Moreover, the SK mode growth of quantum dots is not applicable to homoepitaxy or close lattice matched heterostructures, such as GaAs/AlGaAs. Fabricating nanostructures using the state-of-the-art lithography techniques, such as electron beam lithography, has significant drawbacks in that it is inherently very slow and feature sizes are limited by the proximity effect. Here we present an alternative approach to realizing homoepitaxy of highly ordered GaAs nanodot arrays on GaAs substrates using nanochannel alumina (NCA) templates.