Abstract: A semiconductor device includes a first conductivity type semiconductor layer, a second conductivity type region selectively formed in the semiconductor layer, a second conductivity type peripheral impurity region formed around the second conductivity type region in the semiconductor layer, and a Schottky electrode that is formed on the semiconductor layer and that forms a Schottky junction portion between a first conductivity type part of the semiconductor layer and the Schottky electrode, and, in the semiconductor device, a pn junction portion between the peripheral impurity region and the first conductivity type part of the semiconductor layer has a higher withstand voltage than a Zener voltage VZ of a Zener diode made of a pn junction portion between the second conductivity type region and the first conductivity type part of the semiconductor layer.

Abstract: A Schottky barrier diode includes a first semiconductor layer having depressions on a top surface thereof, and having a guard ring extending from the top surface to an inner position of the first semiconductor layer, the guard ring including portions arranged with the depressions interposed therebetween when viewed in a direction perpendicular to the top surface; the diode further includes an insulation layer having portions arranged with the depressions interposed therebetween when viewed in the perpendicular direction, a first metal layer extending as bridging inside and outside of the depressions and the insulation layer, the first metal layer having a first end on the insulation layer, and a second metal layer formed on the first metal layer and having a second end on the insulation layer, the second end being flush with the first end.

Abstract: A semiconductor device includes a first conductivity type semiconductor layer, a second conductivity type region selectively formed in the semiconductor layer, a second conductivity type peripheral impurity region formed around the second conductivity type region in the semiconductor layer, and a Schottky electrode that is formed on the semiconductor layer and that forms a Schottky junction portion between a first conductivity type part of the semiconductor layer and the Schottky electrode, and, in the semiconductor device, a pn junction portion between the peripheral impurity region and the first conductivity type part of the semiconductor layer has a higher withstand voltage than a Zener voltage VZ of a Zener diode made of a pn junction portion between the second conductivity type region and the first conductivity type part of the semiconductor layer.

Abstract: A Schottky barrier diode includes a first semiconductor layer having depressions on a top surface thereof, and having a guard ring extending from the top surface to an inner position of the first semiconductor layer, the guard ring including portions arranged with the depressions interposed therebetween when viewed in a direction perpendicular to the top surface; the diode further includes an insulation layer having portions arranged with the depressions interposed therebetween when viewed in the perpendicular direction, a first metal layer extending as bridging inside and outside of the depressions and the insulation layer, the first metal layer having a first end on the insulation layer, and a second metal layer formed on the first metal layer and having a second end on the insulation layer, the second end being flush with the first end.

Abstract: A Schottky barrier diode includes a first semiconductor layer having depressions on a top surface thereof, and having a guard ring extending from the top surface to an inner position of the first semiconductor layer, the guard ring including portions arranged with the depressions interposed therebetween when viewed in a direction perpendicular to the top surface; the diode further includes an insulation layer having portions arranged with the depressions interposed therebetween when viewed in the perpendicular direction, a first metal layer extending as bridging inside and outside of the depressions and the insulation layer, the first metal layer having a first end on the insulation layer, and a second metal layer formed on the first metal layer and having a second end on the insulation layer, the second end being flush with the first end.

Abstract: A Schottky barrier diode includes a first semiconductor layer having depressions on a top surface thereof, and having a guard ring extending from the top surface to an inner position of the first semiconductor layer, the guard ring including portions arranged with the depressions interposed therebetween when viewed in a direction perpendicular to the top surface; the diode further includes an insulation layer having portions arranged with the depressions interposed therebetween when viewed in the perpendicular direction, a first metal layer extending as bridging inside and outside of the depressions and the insulation layer, the first metal layer having a first end on the insulation layer, and a second metal layer formed on the first metal layer and having a second end on the insulation layer, the second end being flush with the first end.

Abstract: A Schottky barrier diode includes a semiconductor layer having a plurality of trenches formed by digging in from a top surface and having mesa portions formed between adjacent trenches, and a Schottky metal formed to contact the top surface of the semiconductor layer including inner surfaces of the trenches.

Abstract: A light source unit has a substrate, a light source that is mounted to the substrate. The light source includes; a first emission part that emits a forward light, the forward light being a laser light in an oscillation state; a second emission part that is located on a side opposite to the first emission part and that emits a rearward light, the rearward light being a laser light in an oscillation state; and a light leakage part located at a position different from the first emission part and the second emission part. The light source further includes a photodetector that is provided on the substrate, wherein the photodetector has a light receiving surface for detecting a leakage light that leaks from the light leakage part.

Abstract: A light source unit has a substrate, a light source that is mounted to the substrate. The light source includes; a first emission part that emits a forward light, the forward light being a laser light in an oscillation state; a second emission part that is located on a side opposite to the first emission part and that emits a rearward light, the rearward light being a laser light in an oscillation state; and a light leakage part located at a position different from the first emission part and the second emission part. The light source further includes a photodetector that is provided on the substrate, wherein the photodetector has a light receiving surface for detecting a leakage light that leaks from the light leakage part.

Abstract: A sub-mount having a photodiode region, includes a photodiode which has a first conductivity-type layer arranged in a surface portion of the sub-mount of the photodiode region to form a light-receiving surface and a second conductivity-type region arranged below the first conductivity-type layer and is configured to receive at the light-receiving surface a light emitted from a light-emitting element and convert the light into a photocurrent. A peak light-receiving wavelength at which the photocurrent of the photodiode becomes its maximum value is more than or equal to a minimum emission wavelength of the light-emitting element and less than or equal to a maximum emission wavelength of the light-emitting element.

Abstract: A Schottky barrier diode includes a semiconductor layer having a plurality of trenches formed by digging in from a top surface and having mesa portions formed between adjacent trenches, and a Schottky metal formed to contact the top surface of the semiconductor layer including inner surfaces of the trenches.

Abstract: A Schottky barrier diode includes a semiconductor layer having a plurality of trenches formed by digging in from a top surface and having mesa portions formed between adjacent trenches, and a Schottky metal formed to contact the top surface of the semiconductor layer including inner surfaces of the trenches.

Abstract: A plurality of laser diode units is tested in a bar state, each of the laser diode units in which a laser diode that includes a first electrode and a second electrode formed on surfaces facing each other and that is mounted on a mounting surface of a submount such that the first electrode faces the mounting surface of the submount.

Abstract: A sub-mount having a photodiode region, includes a photodiode which has a first conductivity-type layer arranged in a surface portion of the sub-mount of the photodiode region to form a light-receiving surface and a second conductivity-type region arranged below the first conductivity-type layer and is configured to receive at the light-receiving surface a light emitted from a light-emitting element and convert the light into a photocurrent. A peak light-receiving wavelength at which the photocurrent of the photodiode becomes its maximum value is more than or equal to a minimum emission wavelength of the light-emitting element and less than or equal to a maximum emission wavelength of the light-emitting element.

Abstract: A plurality of laser diode units is tested in a bar state, each of the laser diode units in which a laser diode that includes a first electrode and a second electrode formed on surfaces facing each other and that is mounted on a mounting surface of a submount such that the first electrode faces the mounting surface of the submount.

Abstract: A Schottky barrier diode includes a semiconductor layer having a plurality of trenches formed by digging in from a top surface and having mesa portions formed between adjacent trenches, and a Schottky metal formed to contact the top surface of the semiconductor layer including inner surfaces of the trenches.

Abstract: A lubricated aromatic polyester copolymer composition comprises an aromatic polyester copolymer of a mixture of terephthalic acid and isophthalic acid or derivative thereof at a molar ratio of terephthalic acid group to isophthalic acid group of 9:1 to 1:9 and a bisphenol having the formula ##STR1## wherein --X-- represents --O--, --S--, --SO.sub.2 --, --CO--, or either of an alkylene group or an alkylidene group which can be substituted by a hydrocarbon group having one or more carbon atom or a halogen atom or a halohydrocarbon group; and R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.1 ', R.sub.2 ', R.sub.3 ', and R.sub.4 ' respectively represent hydrogen atom, a halogen atom, hydroxyl group or a hydrocarbon group; and a specific lubricant comprising more than 70 wt. % of n-paraffin having carbon atoms of 16 to 40 at a ratio of 0.05 to 5 wt. % based on said polyester copolymer.