Patent ID: 7759689

Claim:
A light emitting device having improved quantum efficiency, the light emitting device comprising: a substrate having a top surface; a buffer layer of Gallium Nitride (GaN) disposed on the top surface of the substrate; a dielectric mask layer having a pattern of openings formed therein; a layer of n-type or p-type GaN disposed on the buffer layer and extending vertically through each of the openings formed in the dielectric mask layer and extending laterally away from a periphery of each opening both immediately above and immediately below each opening, the GaN extending vertically and laterally through the openings formed in the dielectric mask layer to create a periodically varying refractive index profile in the light emitting device; a quantum well (QW) layer disposed above the patterned dielectric mask layer and above the layer of GaN that extends vertically through the openings formed in the dielectric mask layer, said QW layer providing an active region of the light emitting device in which electrons are converted into photons, said periodically varying refractive index profile promoting confinement of light in the active region; and a layer of n-type or p-type GaN disposed above the active region, wherein if the GaN extending vertically and laterally through the openings formed in the dielectric mask layer is n-type GaN, then the layer of GaN disposed above the active region is p-type GaN, and wherein if the GaN extending vertically and laterally through the openings formed in the dielectric mask layer is p-type GaN, then the GaN disposed above the active region is n-type GaN.