Patent ID: 8563995

Claim:
A light-emitting device comprising: a template comprising: a substrate; and a nested superlattice on said substrate wherein said nested superlattice comprises Al 1-x-y In y Ga x N wherein 0≦x≦α and 0≦y≦1 with x increasing with distance from said substrate; an ultraviolet light-emitting structure on said template wherein said ultraviolet light-emitting structure comprises: a first layer with a first conductivity comprising Al 1-x-y In y Ga x N wherein α≦x; a light emitting quantum well region above said first layer comprising Al 1-x-y In y Ga x N wherein α≦x≦b; and a second layer over said light emitting quantum well with a second conductivity comprising Al 1-x-y In y Ga x N and a first electrical contact in electrical connection with said first layer; a second electrical contact in electrical connection with said second layer; and whereby said α, b and y are selected such that when an electrical potential is applied to said first electrical contact and said second electrical contact said device emits ultraviolet light.