| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly reliable AlGaInP light emitting element having a high emission output, and an epitaxial wafer for light emitting element. SOLUTION: In an A1GaInP material, the degree of diffusion of dopant decreases as the Al composition increases, the dopant is trapped more at an interface as the degree of lattice mismatch increases on the interface, and diffusion from a layer having a larger lattice constant to a layer having a small lattice constant is retarded. Diffusion of dopant from the current diffusion layer 16 side into an active layer 14 can be prevented by inserting a diffusion stop layer 17 of multilayer structure having a high Al composition and different lattice constants between adjacent layers, between the active layer 14 and the p-type current diffusion layer 16. More specifically, effective current diffusion, reduction in working voltage and high optical output can be realized because the dopant is not diffused into the active layer 14 even if the current diffusion layer 16 or a p-type clad layer 15 has a high carrier density. |
