Abstract: An edge-emitting type 650 nm band red semiconductor laser device is provided, which includes a resonator structure having an active layer on a semiconductor substrate. A low reflection three-layer film is provided on an emitting edge face of the resonator structure and a high reflection multi-layer film is provided on a rear edge face of the resonator structure. The low reflection three-layer film is formed by sequentially stacking a first Al2O3 film having a thickness of 10 nm, an Si3N4 film having a thickness of 190 nm, and a second Al2O3 film having a thickness of 10 nm on the emitting edge face by a sputtering process. The edge reflectance at the emitting edge face is set to 10%. The high reflection multi-layer film is formed by alternatively stacking Al2O3 films and a-Si films on the rear edge face.

Abstract: A semiconductor laser device includes an inner lower clad layer formed on a semiconductor layer, an active layer formed on the inner lower clad layer, an inner upper clad layer formed the active layer, a blocking layer formed on the inner upper clad layer to block current, wherein the blocking layer having a concave portion, and an outer upper clad layer formed to cover the blocking layer. Carriers are injected to the active layer through the outer upper clad layer and the concave portion of the blocking layer.

Abstract: A semiconductor laser device includes an inner lower clad layer formed on a semiconductor layer, an active layer formed on the inner lower clad layer, an inner upper clad layer formed the active layer, a blocking layer formed on the inner upper clad layer to block current, wherein the blocking layer having a concave portion, and an outer upper clad layer formed to cover the blocking layer. Carriers are injected to the active layer through the outer upper clad layer and the concave portion of the blocking layer.