Gan group semiconductor light-emitting element with concave and convex structures on the substrate and a production method thereof

Abstract

Concaves and convexesare formed by processing the surface layer of a first layer, and second layerhaving a different refractive index from the first layer is grown while burying the concaves and convexes (or first crystalis grown as concaves and convexes on crystal layer S to be the base of the growth, and second crystalis grown, which has a different refractive index from the first crystal). After forming these concavo-convex refractive index interfaces(), an element structure, wherein semiconductor crystal layers containing a light-emitting layer A are laminated, is formed. As a result, the light in the lateral direction, which is generated in the light-emitting layer changes its direction by an influence of the concavo-convex refractive index interface and heads toward the outside. Particularly, when an ultraviolet light is to be emitted using InGaN as a material of a light-emitting layer, a quantum well structure is employed and all the layers between the quantum well structure and the low temperature buffer layer are formed of a GaN crystal, removing AlGaN. The quantum well structure preferably consists of a well layer made of InGaN and a barrier layer made of GaN, and the thickness of the barrier layer is preferably 6 nm–30 nm.