Preparation of substrates intended for the growth of lower threading dislocation densities within nitride Based UV multiple quantum wells

In this study a variety of nano-patterning techniques were applied to III-N device fabrication. A block co-polymer/metal oxide novel surface texturing method was utilised to achieve a long ranged ordered template. Nano-sphere lithography was also applied to UV multiple quantum well (MQW) structural growth using a silica nanoparticle monolayer as the mask. The monolayer was produced by a self-assembly technique without the need for either a spin coater or Langmuir-Blodgett trough resulting in a low cost arrangement. Using these nano-sized masks allows for the production of nano-rods in a much simpler method than previously used techniques. For comparison nano-rods were made by electron beam lithography at various diameters and lengths for a comprehensive investigation of crystal defects, in particular threading dislocations (TDs).