Abstract

For QD based devices, non-uniformity of size and shape is clearly undesirable, as the resulting structures will exhibit a broad range of electronic and optical properties, effectively smearing out the sought-after zero-dimensional behaviour of the dot ensemble [1]. Seeded self-ordering, which involves the self-formation of nanostructures at nucleation sites introduced by a substrate patterning process, is particularly attractive because it allows for control over the site of the nanostructures while maintaining high quality and uniformity of QD arrays [2,3]. We report an inhomogeneous broadening in the range of 1meV for Q D arrays fabricated by organo-metallic chemical vapor deposition (OMCVD) on pre-patterned substrates. Various techniques beginning with processing of pyramidal recesses to certain growth optimizations were employed to improve the homogeneity of the QDs grown into the pyramidal recesses.

© 2009 IEEE