Abstract: A semiconductor light emitting device has a double heterostructure. The device is composed of an active layer and clad layers that sandwich the active layer. At least one of the clad layers has a multilayer structure having at least two element layers. The Al mole fraction of an element layer, which is proximal to the active layer, of the multilayer structure is smaller than that of the other element layer thereof distal from the active layer. This arrangement improves the crystal quality of an interface between the active layer and the clad layer of multilayer structure and effectively confines carriers in the active layer.

Abstract: A semiconductor light emitting device has a semiconductor substrate (1). On a first principal plane of the substrate, an emission layer is formed. In a predetermined region on the emission layer, a current blocking layer (10) is formed. On the current blocking layer, an excitation electrode (20) is formed. A substrate electrode (9) is formed on a second principal plane of the substrate. The excitation electrode is composed of a bonding pad (21) and a current supply electrode (22). The current blocking layer is under the bonding pad. The current blocking layer prevents a current from flowing under the bonding pad. The current supply electrode improves the light emission efficiency of the device.

Abstract: A semiconductor light emitting device has a double heterostructure. The device is composed of an active layer and clad layers that sandwich the active layer. At least one of the clad layers has a multilayer structure having at least two element layers. The Al mole fraction of an element layer, which is proximal to the active layer, of the multilayer structure is smaller than that of the other element layer thereof distal from the active layer. This arrangement improves the crystal quality of an interface between the active layer and the clad layer of multilayer structure and effectively confines carriers in the active layer.

Abstract: A semiconductor light-emitting element has a crystal layer formed from aluminum of a high mol ratio of 60% or greater on the light producing surface. In the semiconductor light-emitting element, a conductive crystal with aluminum of a mol ratio of 50% or less, or a conductive crystal containing no aluminum is formed on the high aluminum crystal layer.

Abstract: A semiconductor light-emitting element has a crystal layer formed from aluminum of a high mol ratio of 60% or greater on the light producing surface. In the semiconductor light-emitting element, a conductive crystal with aluminum of a mol ratio of 50% or less, or a conductive crystal containing no aluminum is formed on the high aluminum crystal layer.