Abstract: A vertical cavity surface emitting laser includes: a supporting base having a principal surface including III-V compound semiconductor containing gallium and arsenic as constituent elements; and a post disposed on the principal surface. The post has a lower spacer region including a III-V compound semiconductor containing gallium and arsenic as group-III elements, and an active layer having a quantum well structure disposed on the lower spacer region. The quantum well structure has a concentration of carbon in a range of 2×1016 cm?3 or more to 5×1016 cm?3 or less. The quantum well structure includes a well layer and a barrier layer. The well layer includes a III-V compound semiconductor containing indium as a group-III element, and the barrier layer includes a III-V compound semiconductor containing indium and aluminum as group-III elements. The lower spacer region is disposed between the supporting base and the active layer.

Abstract: A vertical cavity surface emitting laser includes: an active layer; a first laminate for a first distributed Bragg reflector; and a first intermediate layer disposed between the active layer and the first laminate. The first intermediate layer has first and second portions. The first laminate, the first and second portions of the first intermediate layer, and the active layer are arranged along a direction of a first axis. The first laminate and the first portion of the first intermediate layer each include a first dopant. The active layer has a first-dopant concentration of less than 1×1016 cm?3. The first portion of the first intermediate layer has a first-dopant concentration smaller than that of the first laminate. The second portion of the first intermediate layer has a first-dopant concentration smaller than that of the first portion of the first intermediate layer.

Abstract: A living body optical measurement apparatus of the present invention includes: a light irradiation/measurement unit for irradiating light to an object and measuring the light passed through the object, a signal processing unit for processing measurement data of the light irradiation/measurement unit and creating a living body optical measurement image, and a position measurement unit for measuring positions where light is irradiated to an object and where the passing light is extracted from the object, the light irradiation/measurement unit includes plural optical fibers. The light irradiation/measurement unit includes plural optical fibers, plural optical fiber plugs attached to the plural optical fibers respectively, and a holder fixed detachably at a measurement site of an object and holds the plural optical fiber plugs.

Abstract: A layered semiconductor includes a base layer including a substrate and a buffer layer, and a drift layer which is disposed on the base layer and is made of GaN and whose conductivity type is an n-type. The drift layer has an average n-type impurity concentration of 1.5×1016 cm?3 or less in a radial direction of the substrate, and the difference between the maximum n-type impurity concentration and the minimum n-type impurity concentration is 1.5×1015 cm?3 or less.

Abstract: Provided are a semiconductor device and an optical sensor device, each having reduced dark current, and detectivity extended toward longer wavelengths in the near-infrared. Further, a method for manufacturing the semiconductor device is provided. The semiconductor device 50 includes an absorption layer 3 of a type II (GaAsSb/InGaAs) MQW structure located on an InP substrate 1, and an InP contact layer 5 located on the MQW structure. In the MQW structure, a composition x (%) of GaAsSb is not smaller than 44%, a thickness z (nm) thereof is not smaller than 3 nm, and z??0.4x+24.6 is satisfied.

Abstract: A laminated body includes: a substrate portion composed of silicon carbide; and a graphene film disposed on a first main surface of the substrate portion, the graphene film having an atomic arrangement oriented with respect to an atomic arrangement of the silicon carbide of the substrate portion. A region in which a value of G?/G in Raman spectrometry is not less than 1.2 is not less than 10% in an area ratio in an exposed surface of the graphene film, the exposed surface being a main surface of the graphene film opposite to the substrate portion.

Abstract: A layered semiconductor includes a base layer including a substrate and a buffer layer, and a drift layer which is disposed on the base layer and is made of GaN and whose conductivity type is an n-type. The drift layer has an average n-type impurity concentration of 1.5×1016 cm?3 or less in a radial direction of the substrate, and the difference between the maximum n-type impurity concentration and the minimum n-type impurity concentration is 1.5×1015 cm?3 or less.

Abstract: A semiconductor device and the like having high quantum efficiency or high sensitivity in a near-infrared to infrared region is provided. The semiconductor device includes: a substrate; a multiple quantum well structure disposed on the substrate, and including a plurality of pairs of a layer a and a layer b; and a crystal-adjusting layer disposed between the substrate and the multiple quantum well structure. The crystal-adjusting layer includes a first adjusting layer which is made of the same material as the substrate and is in contact with the substrate, and a second adjusting layer which is made of the same material as the layer a or the layer b of the multiple quantum well structure and is in contact with the multiple quantum well structure.

Abstract: A laminated body includes: a substrate portion composed of silicon carbide; and a graphene film disposed on a first main surface of the substrate portion, the graphene film having an atomic arrangement oriented with respect to an atomic arrangement of the silicon carbide of the substrate portion. A region in which a value of G?/G in Raman spectrometry is not less than 1.2 is not less than 10% in an area ratio in an exposed surface of the graphene film, the exposed surface being a main surface of the graphene film opposite to the substrate portion.

Abstract: A semiconductor device and the like having high quantum efficiency or high sensitivity in a near-infrared to infrared region is provided. The semiconductor device includes: a substrate; a multiple quantum well structure disposed on the substrate, and including a plurality of pairs of a layer a and a layer b; and a crystal-adjusting layer disposed between the substrate and the multiple quantum well structure. The crystal-adjusting layer includes a first adjusting layer which is made of the same material as the substrate and is in contact with the substrate, and a second adjusting layer which is made of the same material as the layer a or the layer b of the multiple quantum well structure and is in contact with the multiple quantum well structure.

Abstract: A photodiode and the like capable of preventing the responsivity on the short wavelength side from deteriorating while totally improving the responsivity in a type II MQW structure, is provided. The photodiode is formed on a group III-V compound semiconductor substrate, and includes a pixel. The photodiode includes an absorption layer of a type II MQW structure, which is located on the substrate. The MQW structure includes fifty or more pairs of two different types of group III-V compound semiconductor layers. The thickness of one of the two different types of group III-V compound semiconductor layers, which layer has a higher potential of a valence band, is thinner than the thickness of the other layer.

Abstract: An object of the present invention is to provide a group III-V compound semiconductor photo detector comprising an absorption layer having a group III-V compound semiconductor layer containing Sb as a group V constituent element, and an n-type InP window layer, resulting in reduced dark current. The InP layer 23 grown on the absorption layer 23 contains antimony as impurity, due to the memory effect with antimony which is supplied during the growth of a GaAsSb layer of the absorption layer 21. In the group III-V compound semiconductor photo detector 11, the InP layer 23 contains antimony as impurity and is doped with silicon as n-type dopant. Although antimony impurities in the InP layer 23 generate holes, the silicon contained in the InP layer 23 compensates for the generated carriers. As a result, the second portion 23d of the InP layer 23 has sufficient n-type conductivity.

Abstract: Provided are an epitaxial wafer, a photodiode, and the like that include an antimony-containing layer and can be efficiently produced such that protruding surface defects causing a decrease in the yield can be reduced and impurity contamination causing degradation of the performance can be suppressed. The production method includes a step of growing an antimony (Sb)-containing layer on a substrate 1 by metal-organic vapor phase epitaxy using only metal-organic sources; and a step of growing, on the antimony-containing layer, an antimony-free layer including a window layer 5, wherein, from the growth of the antimony-containing layer to completion of the growth of the window layer, the growth is performed at a growth temperature of 425° C. or more and 525° C. or less.

Abstract: Provided are a semiconductor device and an optical sensor device, each having reduced dark current, and detectivity extended toward longer wavelengths in the near-infrared. Further, a method for manufacturing the semiconductor device is provided. The semiconductor device 50 includes an absorption layer 3 of a type II (GaAsSb/InGaAs) MQW structure located on an InP substrate 1, and an InP contact layer 5 located on the MQW structure. In the MQW structure, a composition x (%) of GaAsSb is not smaller than 44%, a thickness z (nm) thereof is not smaller than 3 nm, and z??0.4x+24.6 is satisfied.

Abstract: A railway vehicle includes an underframe, side structures, end structures, and a roof structure which form a vehicle body with a crushable zone. In the crushable zone, a slide center beam and a guide center beam are connected with each other by a lower fuse member, and a slide bar and guide frame are connected with each other by an upper fuse member. When the fuse members are broken, upper and lower slide portions are brought into a slidable state.

Abstract: Provided are a semiconductor device and an optical sensor device, each having reduced dark current, and detectivity extended toward longer wavelengths in the near-infrared. Further, a method for manufacturing the semiconductor device is provided. The semiconductor device 50 includes an absorption layer 3 of a type II (GaAsSb/InGaAs) MQW structure located on an InP substrate 1, and an InP contact layer 5 located on the MQW structure. In the MQW structure, a composition x (%) of GaAsSb is not smaller than 44%, a thickness z (nm) thereof is not smaller than 3 nm, and z??0.4x+24.6 is satisfied.

Abstract: A living body optical measurement apparatus of the present invention includes: a light irradiation/measurement unit for irradiating light to an object and measuring the light passed through the object, a signal processing unit for processing measurement data of the light irradiation/measurement unit and creating a living body optical measurement image, and a position measurement unit for measuring positions where light is irradiated to an object and where the passing light is extracted from the object, the light irradiation/measurement unit includes plural optical fibers. The light irradiation/measurement unit includes plural optical fibers, plural optical fiber plugs attached to the plural optical fibers respectively, and a holder fixed detachably at a measurement site of an object and holds the plural optical fiber plugs.

Abstract: An object of the present invention is to provide a group III-V compound semiconductor photo detector comprising an absorption layer having a group III-V compound semiconductor layer containing Sb as a group V constituent element, and an n-type InP window layer, resulting in reduced dark current. The InP layer 23 grown on the absorption layer 23 contains antimony as impurity, due to the memory effect with antimony which is supplied during the growth of a GaAsSb layer of the absorption layer 21. In the group III-V compound semiconductor photo detector 11, the InP layer 23 contains antimony as impurity and is doped with silicon as n-type dopant. Although antimony impurities in the InP layer 23 generate holes, the silicon contained in the InP layer 23 compensates for the generated carriers. As a result, the second portion 23d of the InP layer 23 has sufficient n-type conductivity.

Abstract: The present invention provides a light receiving element array etc., having a high light-reception sensitivity in the near-infrared region, an optical sensor device, and a method for producing the light receiving element array. A light receiving element array 55 includes an n-type buffer layer 2 disposed on an InP substrate 1, an absorption layer 3 having a type-II MQW, a contact layer 5 disposed on the absorption layer, and a p-type region extending to the n-type buffer layer 2 through the absorption layer 3, wherein the p-type region formed by selective diffusion is separated from the p-type region of an adjacent light receiving element by a region that is not subjected to selective diffusion, and, in the n-type buffer layer, a p-n junction 15 is formed on a crossed face of a p-type carrier concentration of the p-type region and an n-type carrier concentration of the buffer layer.