Abstract: A semiconductor laser device includes a semiconductor laser element, a sub mount member, a mount section having an upper surface on which the semiconductor laser element is mounted with the sub mount member interposed therebetween, a lead pin disposed at left and right sides of the mount section, a retainer that retains the mount section and the lead pin together and that is composed of an insulative material, and a protrusion protruding toward the left and right sides of the mount section. A lower surface of the mount section is parallel to an upper surface of the mount section and protrudes from a lower surface of the retainer.

Abstract: In a semiconductor laser device that includes: a semiconductor laser element that outputs light from an output portion; and a metal stem that holds the semiconductor laser element, the metal stem includes a base that has a reference surface on an upper surface and a protrusion portion that protrudes upward from the reference surface, and the protrusion portion is provided with an installation surface on which the semiconductor laser element is installed and a side surface which is disposed on an identical plane with a part of an outer circumferential surface of the base.

Abstract: A semiconductor laser device includes a semiconductor laser element, a sub mount member, a mount section having an upper surface on which the semiconductor laser element is mounted with the sub mount member interposed therebetween, a lead pin disposed at left and right sides of the mount section, a retainer that retains the mount section and the lead pin together and that is composed of an insulative material, and a protrusion protruding toward the left and right sides of the mount section. A lower surface of the mount section is parallel to an upper surface of the mount section and protrudes from a lower surface of the retainer.

Abstract: In a semiconductor laser device that includes: a semiconductor laser element that outputs light from an output portion; and a metal stem that holds the semiconductor laser element, the metal stem includes a base that has a reference surface on an upper surface and a protrusion portion that protrudes upward from the reference surface, and the protrusion portion is provided with an installation surface on which the semiconductor laser element is installed and a side surface which is disposed on an identical plane with a part of an outer circumferential surface of the base.

Abstract: In a semiconductor laser device, a first lead has a mounting portion for mounting a semiconductor laser element on its top surface via a submount member, and a lead portion extending from the mounting portion. Given that a direction in which a primary beam is emitted from the laser element is defined as a forward direction, and that a direction vertical to the forward direction and parallel to the top surface of the mounting portion is defined as a lateral direction, the first lead has, in one region of a side face of the mounting portion, a lateral reference surface which is parallel to a side face of the semiconductor laser element and flat. In the one region of the side face of the mounting portion, a recess portion is formed adjacent to the lateral reference surface.

Abstract: In a semiconductor laser device, a first lead has a mounting portion for mounting a semiconductor laser element on its top surface via a submount member, and a lead portion extending from the mounting portion. Given that a direction in which a primary beam is emitted from the laser element is defined as a forward direction, and that a direction vertical to the forward direction and parallel to the top surface of the mounting portion is defined as a lateral direction, the first lead has, in one region of a side face of the mounting portion, a lateral reference surface which is parallel to a side face of the semiconductor laser element and flat. In the one region of the side face of the mounting portion, a recess portion is formed adjacent to the lateral reference surface.

Abstract: In an AlGaInP semiconductor laser device, at least a first conductivity type first cladding layer, an active layer and a second conductivity type second cladding layer are formed on a semiconductor substrate. The second cladding layer forms a stripe-shaped ridge on a side opposite from the substrate, and a first conductivity type current block layer is disposed on both sides of the ridge. The first conductivity type current block layer has a lattice mismatch rate of ?0.20% or more but not more than 0% relative to the semiconductor substrate. The lattice mismatch rate may be uniform within the current block layer. Alternatively, the lattice mismatch rate may increase continuously or stepwise with an increasing distance from a portion of the second conductivity type second cladding layer other than the ridge.

Abstract: The laser semiconductor device includes a semiconductor substrate, a first clad layer of a first conductivity type, an active layer, a second clad layer of a second conductivity type, and a protective layer of the second conductivity type, and peak wavelength of photo luminescence of an active layer (window region) in a region near an end surface of a laser resonator is smaller than peak wavelength of photo luminescence of the active layer (active region) in an inner region of the laser resonator. In the active layer in the region near the end surface of the laser resonator, first impurity atoms of a second conductivity and second impurity atoms of the second conductivity exist mixedly, with the concentration of the first impurity atoms being higher than that of the second impurity atoms.

Abstract: In a semiconductor laser element, a semiconductor layer interface 116 containing oxygen atoms is present above an active layer 103 in at least an internal region of a laser resonator. Also, the peak wavelength of photoluminescence of the active layer 103 in regions in the vicinity of end faces of the laser resonator is made shorter than that of the active layer in the internal region of the laser resonator. In the internal region of the laser resonator, vacancies (crystal defects) produced above and in the neighborhood of the semiconductor layer interface containing oxygen atoms are captured at this semiconductor layer interface. Diffusion of the vacancies to the active layer is thus suppressed.

Abstract: In an AlGaInP semiconductor laser device, at least a first conductivity type first cladding layer, an active layer and a second conductivity type second cladding layer are formed on a semiconductor substrate. The second cladding layer forms a stripe-shaped ridge on a side opposite from the substrate, and a first conductivity type current block layer is disposed on both sides of the ridge. The first conductivity type current block layer has a lattice mismatch rate of ?0.20% or more but not more than 0% relative to the semiconductor substrate. The lattice mismatch rate may be uniform within the current block layer. Alternatively, the lattice mismatch rate may increase continuously or stepwise with an increasing distance from a portion of the second conductivity type second cladding layer other than the ridge.

Abstract: A semiconductor laser device has a quantum well active layer including a well layer and a barrier layer laminated on a semiconductor substrate. The quantum well active layer contains II group atoms such as Zn atoms. The quantum well active layer is so formed that a bandgap of the quantum well active layer in the vicinity of an end surface of a laser resonator is larger than a bandgap of the quantum well active layer inside the laser resonator. The II group atoms contained in the quantum well active layer inside the laser resonator make up for vacancies introduced therein so as to inhibit fluctuation of the bandgap of the quantum well active layer inside the laser resonator and thereby to enhance long-term reliability of the semiconductor laser device.

Abstract: In a semiconductor laser device having a quantum well active layer, an undoped thin spacer layer is formed between an undoped optical guide layer and a p-type cladding layer. The thickness of the spacer layer is preferably 5 nm or more but less than 10 nm. The spacer layer absorbs impurities diffusing thereinto from the p-type cladding layer. Thus, the dopant is prevented from being diffused into the undoped optical guide layer.

Abstract: A semiconductor laser device, which is made from an AlGaInP-based material, comprising:

Abstract: The laser semiconductor device includes a semiconductor substrate, a first clad layer of a first conductivity type, an active layer, a second clad layer of a second conductivity type, and a protective layer of the second conductivity type, and peak wavelength of photo luminescence of an active layer (window region) in a region near an end surface of a laser resonator is smaller than peak wavelength of photo luminescence of the active layer (active region) in an inner region of the laser resonator. In the active layer in the region near the end surface of the laser resonator, first impurity atoms of a second conductivity and second impurity atoms of the second conductivity exist mixedly, with the concentration of the first impurity atoms being higher than that of the second impurity atoms.

Abstract: In a semiconductor laser element, a semiconductor layer interface 116 containing oxygen atoms is present above an active layer 103 in at least an internal region of a laser resonator. Also, the peak wavelength of photoluminescence of the active layer 103 in regions in the vicinity of end faces of the laser resonator is made shorter than that of the active layer in the internal region of the laser resonator. In the internal region of the laser resonator, vacancies (crystal defects) produced above and in the neighborhood of the semiconductor layer interface containing oxygen atoms are captured at this semiconductor layer interface. Diffusion of the vacancies to the active layer is thus suppressed.

Abstract: A semiconductor laser device has a quantum well active layer including a well layer and a barrier layer laminated on a semiconductor substrate. The quantum well active layer contains II group atoms such as Zn atoms. The quantum well active layer is so formed that a bandgap of the quantum well active layer in the vicinity of an end surface of a laser resonator is larger than a bandgap of the quantum well active layer inside the laser resonator. The II group atoms contained in the quantum well active layer inside the laser resonator make up for vacancies introduced therein so as to inhibit fluctuation of the bandgap of the quantum well active layer inside the laser resonator and thereby to enhance long-term reliability of the semiconductor laser device.

Abstract: The method of forming a III-V group compound semiconductor crystalline layer on a semiconductor crystal containing at least V-group compound, includes the steps of: performing the crystal growth of the III-V compound semiconductor crystalline layer; and supplying an n-type dopant and a material compound containing a V-group element onto the semiconductor crystal without causing the crystal growth of the III-V compound semiconductor crystalline layer.