Abstract: The semiconductor laser device includes an active layer, a p-type cladding layer, and a p-type cap layer. The layers are sequentially stacked so that the semiconductor laser device is provided. The p-type cap layer includes both a p-type dopant and an n-type dopant. In another aspect, the p-type cap layer includes a first layer including a first p-type dopant and a second layer including a second p-type dopant having a diffusion coefficient smaller than that of the first p-type dopant. The first layer is far from the active layer, and the second layer is close to the active layer. In further aspect, the p-type cap layer includes carbon (C) as a p-type dopant. According to these configuration, the p-type dopant can be prevented from being diffused in the active layer and the p-type cladding layer.

Abstract: The semiconductor laser device includes an active layer, a p-type cladding layer, and a p-type cap layer. The layers are sequentially stacked so that the semiconductor laser device is provided. The p-type cap layer includes both a p-type dopant and an n-type dopant. In another aspect, the p-type cap layer includes a first layer including a first p-type dopant and a second layer including a second p-type dopant having a diffusion coefficient smaller than that of the first p-type dopant. The first layer is far from the active layer, and the second layer is close to the active layer. In further aspect, the p-type cap layer includes carbon (C) as a p-type dopant. According to these configuration, the p-type dopant can be prevented from being diffused in the active layer and the p-type cladding layer.

Abstract: A semiconductor laser device exhibiting a reduced threshold current with less deterioration in temperature properties in current-optical output performance and excellent beam properties. The semiconductor laser device has a current blocking layer of n-AlInP having a stripe-shaped opening disposed on a first upper cladding layer, the first upper cladding layer and the current blocking layer facing the opening respectively are covered by a buffer layer of p-Al0.7Ga0.5As and a second upper cladding layer of p-(Al0.7Ga0.3)0.5In0.5P is disposed on the buffer layer, to prevent lattice defect formation during growth of a crystalline layer on the surface of the current blocking layer facing the opening.

Abstract: To provide a semiconductor laser device exhibiting a reduced threshold current with less deterioration in temperature properties in current-optical output performance and excellent beam properties, in the semiconductor laser device according to the present invention, a current blocking layer 22 made of n-AlInP having a stripe-shaped opening 24 is disposed on a first upper clad layer 20, the first upper clad layer 20 and the current blocking layer 22 facing the opening 24 respectively are covered by a buffer layer 26 made of p-Al0.5Ga0.5As and a second upper clad layer 28 made of p-(Al0.7Ga0.3)0.5In0.5P is disposed via the buffer layer 26, to prevent lattice defect formation in the crystal layer grown on the surface of the current blocking layer 22 facing the opening 24.