Patent ID: 8218595
Filing Date: 2012-07-10
Classification: B82Y,H01S

Abstract:
1. A GaN edge emitting laser comprising a semi-polar GaN substrate, an active region, an N-side waveguiding layer, a P-side waveguiding layer, an N-type cladding layer, and a P-type cladding layer, wherein: the GaN substrate defines a 20 the N-side waveguiding layer comprises a GaInN/GaN or GaInN/GaInN superlattice (SL) waveguiding layer; the P-side waveguiding layer comprises a GaInN/GaN or GaInN/GaInN superlattice (SL) waveguiding layer; the superlattice layers of the N-side and P-side SL waveguiding layers define respective layer thicknesses that are optimized for waveguide planarity, the layer thicknesses being between approximately 1 nm and approximately 5 nm; the active region is interposed between and extends substantially parallel to the N-side SL waveguiding layer and the P-side SL waveguiding layer; the N-type cladding layer is interposed between the N-side waveguiding layer and the GaN substrate; the P-type cladding layer is formed over the P-side waveguiding layer; and a strain-thickness product of the N-side SL waveguiding layer exceeds its strain relaxation critical value and a strain-thickness product of the N-type cladding layer exceeds its strain relaxation critical value such that resulting strain relaxation is mono-directional along the glide plane of the GaN substrate.