Abstract: Solid state sources offer potential advantages including high brightness, electricity savings, long lifetime, and higher color rendering capability, when compared to incandescent and fluorescent light sources. To date however, many of these advantages have not been borne out in providing white LED lamps for general lighting applications. The inventors have established that surface recombination through non-radiative processes results in highly inefficient electrical injection. Exploiting in-situ grown shells in combination with dot-in-a-wire LED structures to overcome this limitation through the effective lateral confinement offered by the shell, the inventors have demonstrated core-shell dot-in-a-wire LEDs with significantly improved electrical injection efficiency and output power, providing phosphor-free InGaN/GaN nanowire white LEDs operating with milliwatt output power and color rendering indices of 95-98.

Abstract: Solid state sources offers potential advantages including high brightness, electricity savings, long lifetime, and higher color rendering capability, when compared to incandescent and fluorescent light sources. To date however, many of these advantages, however, have not been borne out in providing white LED lamps for general lighting applications. The inventors have established that surface recombination through non-radiative processes results in highly inefficient electrical injection. Exploiting in-situ grown shells in combination with dot-in-a-wire LED structures to overcome this limitation through the effective lateral confinement offered by the shell the inventors have demonstrated core-shell dot-in-a-wire LEDs, with significantly improved electrical injection efficiency and output power, providing phosphor-free InGaN/GaN nanowire white LEDs operating with milliwatt output power and color rendering indices of 95-98.

Abstract: Amongst the candidates for very high efficiency solid state light sources and full solar spectrum solar cells are devices based upon InGaN nanowires. Additionally these nanowires typically require heterostructures, quantum dots, etc which all place requirements for these structures to be grown with relatively few defects and in a controllable reproducible manner. Additionally flexibility according to the device design requires that the nanowire at the substrate may be either InN or GaN. According to the invention a method of growing relatively defect free nanowires and associated structures for group IIIA-nitrides is presented without the requirement for foreign metal catalysts and overcoming the non-uniform growth of prior art non-catalyst growth techniques. According to other embodiments of the invention self-organizing dot-within-a-dot nanowire and dot-within-a-dot-within-a-well nanowire structures are presented.

Abstract: Amongst the candidates for very high efficiency solid state light sources and full solar spectrum solar cells are devices based upon InGaN nanowires. Additionally these nanowires typically require heterostructures, quantum dots, etc which all place requirements for these structures to be grown with relatively few defects and in a controllable reproducible manner. Additionally flexibility according to the device design requires that the nanowire at the substrate may be either InN or GaN. According to the invention a method of growing relatively defect free nanowires and associated structures for group IIIA-nitrides is presented without the requirement for foreign metal catalysts and overcoming the non-uniform growth of prior art non-catalyst growth techniques. According to other embodiments of the invention self-organizing dot-within-a-dot nanowire and dot-within-a-dot-within-a-well nanowire structures are presented.