| 摘要 |
PURPOSE:To perform sufficient light emitting output and an ohmic contact by forming a concentration gradient in which the impurity concentrations of P-type and N-type GaAlAs layers are lower than those of a GaAlAs active layer near a junction boundary to the active layer and the surface becomes high in its concentration. CONSTITUTION:A double hetero structure made of three layers of a P-type GaAlAs clad layer 21, a GaAlAs active layer 22 having mixed crystal ratio necessary for an emitting light wavelength and an N-type GaAlAs clad layer 23 are sequentially grown is provided, and the impurity concentrations of the layers 21, 23 are reduced lower than that of the layer 22 near the junction boundary to the layer 22. An inclined impurity concentration gradient in which the surfaces of the layers 21, 23 become high in concentration is provided. Thus, a high intensity light emitting output is obtained, the electrodes 25, 24 are formed directly on the layers 21, 23, and sufficiently optical output and ohmic contact are obtained in a simple elemental structure. |
