| 摘要 |
PURPOSE:To enable an active layer to confine enough injected carriers and to be improved in light emitting efficiency as satisfying a lattice matching condition with respect to a substrate by a method wherein a first barrier layer, which is thinner and smaller than the active layer in electron affinity, is arranged at the interface of a heterojunction between the active layer and a clad layer. CONSTITUTION:A first barrier layer 5 formed of semiconductor, whose electron affinity Ea is smaller than that of an active layer 4 and is smaller than the layer 4 in thickness, is provided to an interface of the heterojunction between the active layer 4 and a clad layer 6. Therefore, lattice constants of a substrate 1, clad layers 2 and 6, the active layer 4, and the first barrier layer 5 are roughly matched with each other, and as the first barrier layer 5 is thin, the probability that holes subsist in it becomes small. Therefore, electrons injected into the active layers 4 can be restrained from overflowing to the P-side clad layer 6, so that electrons can be confined into the active layer 4. By this setup, a device high in efficiency and operable in the wavelength region of blue light can be obtained. |
