Optical microstructures formed by self-assembly during MBE re-growth of GaAs on pre-patterned substrates

摘要

There is considerable interest in the study of light emission from optical cavities whose dimensions are of the order of a wavelength in all three dimensions. Most work has been carried out on etched structures. We propose and demonstrate a novel method for the fabrication of GaAs semiconductor optical microstructures by selforganization during molecular beam epitaxial growth (MBE) on pre-patterned micron scale mesa structures. The structures formed during this process are pyramidal and the faces of the pyramid are the stable facets formed during the MBE re-growth process. Such a structure, coupled with a planar Bragg reflector, may provide a novel means of achieving three-dimensional confinement of optical modes. We also present calculations of the optical modes, which can be supported within metal clad pyramidal structures and consider the significance of the results for the design and fabrication of microcavities.