Abstract: The present invention provides a sub-mount type device for emitting light which has high speed response and yet can radiate heat sufficiently. The sub-mount type device for emitting light comprises a heat sink (4), a sub-mount body (62) mounted on the heat sink (4) which comprises an insulating layer (38) with a upper face and a lower face, a upper electrode (42) on the upper face and a lower electrode 44 and 36 on the lower face, the insulating layer having two parts of the insulating layer (38) thickness of which is different, and a chip (30) for emitting light above the thinner part (39) of the insulating layer (38).

Abstract: There is provided a process for fabricating a highly reliable semiconductor laser device operable at a low current with an increased yield, which process includes the steps of: (a) forming a lower clad layer on a semiconductor substrate; (b) forming an active layer of a material larger in refractive index and smaller in forbidden band width than the lower clad layer; (c) forming a first upper clad layer of a material smaller in refractive index and larger in forbidden band width than the active layer; (d) forming an etch stop layer made of GaAs on the first upper clad layer; (e) forming a current-blocking layer of a material smaller in refractive index and larger in forbidden band width than the first upper clad layer; (f) forming a stripe cavity by etching at least a portion of the current-blocking layer down to the etch stop layer; (g) evaporating the etch stop layer remaining in the stripe cavity; (h) forming a second upper clad layer of a material smaller in refractive index and larger in forbidden band w

Abstract: A highly reliable semiconductor laser device capable of exhibiting a good current-light output characteristic and a fabrication process therefore is provided. The semiconductor laser device is provided with a step in a region adjacent a laser-light-emitting edge to separate an upper electrode into two, one of which is located adjacent the laser-light-emitting edge and does not allow current to flow in the underlying portion even if the other is applied with voltage, thereby forming a current-noninjection region in the region adjacent the later-light-emtting edge. Due to such an arrangement, deterioration of device characteristics due to local heat generation can be assuredly prevented without changing the structure adjacent the active layer and the current-confining structure which dominate the characteristics of the semiconductor laser.

Abstract: A self-aligned type, high-power semiconductor laser is provided which exhibits multi-longitudinal mode oscillation in the low-power operation (at a light power output of, for example, 3 mW) through it is of a refractive index guiding structure capable of single transverse mode oscillation in up to the high-power operation. Specifically, the semiconductor laser is of an AlGaAs system and has a waveguide mechanism resulting from complex refractive index, and wherein a current-blocking layer is 2000 to 6000 .ANG. thick.