Abstract: Semiconductor laser elements are formed on a common substrate. Au plating is formed on principal surfaces of the semiconductor laser elements. The semiconductor laser elements are mounted on a package with solder applied to the Au plating. Areas opposed to each other across a light-emitting area of each semiconductor laser element are designated first and second areas. Average thickness of the Au plating is different in the first and second areas of each semiconductor laser element.

Abstract: A semiconductor laser chip is joined to an AlN sub-mount in a junction-down manner. The sub-mount is joined to a package. The AlN sub-mount is joined to a stem. The direction perpendicular to the irradiation direction of a laser beam emitted from the semiconductor laser chip is the direction of the width of the sub-mount. The thickness and the width of the AlN sub-mount are determined so that the product of the equivalent stress applied to the center of the surface of the semiconductor laser chip joined to the sub-mount and the stress in the direction of the width of the sub-mount does not exceed 70% of the maximum value of the product obtained by changing the thickness and the width of the AlN sub-mount.

Abstract: A method of manufacturing a semiconductor laser includes sequentially forming a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer on top of one another on a semiconductor substrate; forming a ridge in the second conductivity type semiconductor layer; forming a first insulating film on the second conductivity type semiconductor layer at a first temperature; forming a second insulating film on the first insulating film at a second temperature, lower than the first temperature; and forming an electrode on the second insulating film.

Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.

Abstract: A semiconductor laser having a double channel ridge structure includes: a ridge; channel portions located on opposite sides of the ridge, sandwiching the ridge, and having an equivalent refractive index lower than the equivalent refractive index of the ridge; and layers defining outside surfaces of the channel portions and, having an equivalent refractive index higher than the equivalent refractive index of the channel portions. The ridge has a flare ridge structure with a width that is widened toward a light outgoing end surface, and the width of the channel portions where the width of the ridge is the narrowest is wider than the channel portions at the light outgoing end surface.

Abstract: A semiconductor laser device capable of reducing the threshold current and improving luminous efficiency and a method of fabricating the same are obtained. This semiconductor laser device comprises a semiconductor substrate having a principal surface and a semiconductor element layer, formed on the principal surface of the semiconductor substrate, having a principal surface substantially inclined with respect to the principal surface of the semiconductor substrate and including an emission layer.

Abstract: A monolithic semiconductor laser having plural semiconductor lasers having different emission wavelengths from each other, including: a semiconductor substrate; a first double hetero-structure formed within a first area on the semiconductor substrate and having first clad layers disposed above and below a first active layer; and a second double hetero-structure formed within a second area on the semiconductor substrate and having second clad layers disposed above and below a second active layer. The first and second active layers are made of different semiconductor materials from each other. The first clad layers above and below the first active layer are of approximately the same semiconductor materials and the second clad layers above and below the second active layer are of approximately the same semiconductor materials.

Abstract: A semiconductor device capable of stabilizing operations thereof is provided. This semiconductor device comprises a substrate provided with a region having concentrated dislocations at least on part of the back surface thereof, a semiconductor element layer formed on the front surface of the substrate, an insulator film formed on the region of the back surface of the substrate having concentrated dislocations and a back electrode formed to be in contact with a region of the back surface of the substrate other than the region having concentrated dislocations.

Abstract: A semiconductor laser device capable of reducing the threshold current and improving luminous efficiency and a method of fabricating the same are obtained. This semiconductor laser device comprises a semiconductor substrate having a principal surface and a semiconductor element layer, formed on the principal surface of the semiconductor substrate, having a principal surface substantially inclined with respect to the principal surface of the semiconductor substrate and including an emission layer.

Abstract: An electrode pattern for wire-bonding includes: a wire-bonding reference pattern indicating a reference position for determination of a wire-bonding position; and a wire-bonding recognition pattern. The distance between the reference position and a wire-bonding metal portion bonded to the electrode pattern and the distance between the wire-bonding recognition pattern and the wire-bonding metal portion satisfy predetermined relationships.

Abstract: A semiconductor laser chip is joined to an AlN sub-mount in a junction-down manner. The sub-mount is joined to a package. The AlN sub-mount is joined to a stem. The direction perpendicular to the irradiation direction of a laser beam emitted from the semiconductor laser chip is the direction of the width of the sub-mount. The thickness and the width of the AlN sub-mount are determined so that the product of the equivalent stress applied to the center of the surface of the semiconductor laser chip joined to the sub-mount and the stress in the direction of the width of the sub-mount does not exceed 70% of the maximum value of the product obtained by changing the thickness and the width of the AlN sub-mount.

Abstract: A keyboard device for a keyboard instrument, which can be manufactured by a simplified manufacturing process and at reduced manufacturing costs, is disclosed. A keyframe is formed by a molded piece of a synthetic resin. A plurality of front rail pins and a plurality of balance rail pins are arranged in a juxtaposed manner in a left-right direction at a front part and a central part of the keyframe in a front-rear direction. A plurality of keys are made of wood and each have a balance rail pin hole formed in a central portion thereof in the front-rear direction. The keys are swingably supported on the keyframe in a state where the balance rail pins are each engaged with the balance rail pin hole associated therewith and at the same time the keys are prevented from being swung in the left-right direction by the front rail pins associated therewith.

Abstract: An integrated semiconductor laser device capable of improving the properties of a laser beam and reducing the cost for optical axis adjustment is provided. This integrated semiconductor laser device comprises a first semiconductor laser element including a first emission region and having either a projecting portion or a recess portion and a second semiconductor laser element including a second emission region and having either a recess portion or a projecting portion. Either the projecting portion or the recess portion of the first semiconductor laser element is fitted to either the recess portion or the projecting portion of the second semiconductor laser element.

Abstract: An integrated semiconductor laser device capable of improving the properties of a laser beam and reducing the cost for optical axis adjustment is provided. This integrated semiconductor laser device comprises a first semiconductor laser element including a first emission region and having either a projecting portion or a recess portion and a second semiconductor laser element including a second emission region and having either a recess portion or a projecting portion. Either the projecting portion or the recess portion of the first semiconductor laser element is fitted to either the recess portion or the projecting portion of the second semiconductor laser element.

Abstract: A nitride-based semiconductor light-emitting device capable of improving luminous efficiency by reducing light absorption loss in a contact layer is provided. This nitride-based semiconductor light-emitting device comprises a first conductivity type first nitride-based semiconductor layer formed on a substrate, an active layer, formed on the first nitride-based semiconductor layer, consisting of a nitride-based semiconductor layer, a second conductivity type second nitride-based semiconductor layer formed on the active layer, an undoped contact layer formed on the second nitride-based semiconductor layer and an electrode formed on the undoped contact layer.

Abstract: Semiconductor laser elements are formed on a common substrate. Au plating is formed on principal surfaces of the other semiconductor laser elements. The semiconductor laser elements are mounted on a package with solder applied to the Au plating. Areas opposed to each other across a light-emitting area of each semiconductor laser element are designated first and second areas. Average thickness of the Au plating is different in the first and second areas of each semiconductor laser element.

Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.

Abstract: A semiconductor laser is provided which emits laser light in which the intensity center of the far-field pattern in the horizontal direction does not vary with variation of the optical output and in which the shape of the far-field pattern in the horizontal direction is stable. The width of trenches is determined so that the magnitude (E1) of the electric field at the center of a ridge and the magnitude (E2) of the electric field at the edges of the trenches provide a ratio E1/E2 that is larger than 0.0001 and smaller than 0.01. In a semiconductor laser with a double-channel ridge structure, layers having a larger equivalent refractive index than the trenches exist outside the trenches.

Abstract: Provided is a manufacturing method of a nitride semiconductor device having a nitride semiconductor substrate (e.g. GaN substrate) in which dislocation concentrated regions align in stripe formation, the dislocation concentrated regions extending from a front surface to a back surface of the substrate, the manufacturing method being for stacking each of a plurality of nitride semiconductor layers on the front surface of the substrate in a constant film thickness. Grooves are formed on the nitride semiconductor substrate in the immediate areas of dislocation concentrated regions. Each of the nitride semiconductor layers is formed as a crystal growth layer on the main surface of the nitride semiconductor substrate to which the grooves have been formed.

Abstract: An electrode pattern for wire-bonding includes: a wire-bonding reference pattern indicating a reference position for determination of a wire-bonding position; and a wire-bonding recognition pattern. The distance between the reference position and a wire-bonding metal portion bonded to the electrode pattern and the distance between the wire-bonding recognition pattern and the wire-bonding metal portion satisfy predetermined relationships.