PHOTO-ASSISTED EPITAXY OF WURTZITE GAN

"This work proposes to develop innovative methods to use photo-assisted epitaxial growth for GaN in order to reduce the defects that limit device performance. Light can interact with the surface of the substrate and nucleation layer to influence the growthtoward greater perfection. Several mechanisms can be investigated where incident illumination has the potential to reduce the defect density. One mechanism is the enhancement of reactant surface mobility by increasing the jump frequency, or decreasingthe potential barrier, and assisting in moving the reactant to the appropriate lattice site. Alternatively, monochromatic light can be resonant with the energy of the forming defects, changing their effective formation energy. A third mechanism to beinvestigated is the effect of using light to change the chemical potential at the surface, which, in turn, effects the energy of formation of charged defects. Astralux is proposing to develop a new GaN growth method that will lead to materials that willrevolutionize discrete wide bandgap semiconductor device fabrication and integrated circuit production. The opportunity for the improved materials will apply to both the next generation of optoelectronic devices, as well as the specialized market nichesfor high-power microwave electronics."