Abstract: Provided are an epitaxial wafer and a light-emitting element having a type-II MQW formed of III-V compound semiconductors and configured to emit light with a sufficiently high intensity. The method includes a step of growing an active layer having a type-II multi-quantum well structure (MQW) on a III-V compound semiconductor substrate, wherein, in the step of forming the type-II multi-quantum well structure, the type-II multi-quantum well structure is formed by metal-organic vapor phase epitaxy using only metal-organic sources such that a number of pairs of the type-II multi-quantum well structure is 25 or more.

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: A photodetector and a method of manufacturing the photodetector are provided, in which variation in sensitivity is suppressed over the near-infrared region from the short wavelength side including 1.3 ?m to the long wavelength side. The photodetector includes, on an InP substrate, an absorption layer of a type II multiple quantum well structure comprising a repeated structure of a GaAsSb layer and an InGaAs layer, and has sensitivity in the near-infrared region including wavelengths of 1.3 ?m and 2.0 ?m. The ratio of the sensitivity at the wavelength of 1.3 ?m to the sensitivity at the wavelength of 2.0 ?m is not smaller than 0.5 but not larger than 1.6.

Abstract: Provided is a railway vehicle having a configuration which can sufficiently protect the cabin even when large external force is applied to the end structures thereof. The vehicle body of the railway vehicle is formed by joining an underframe 20, side structures 30, end structures 50, and a roof structure 60 together. An upper reinforcement beam 56 in the railroad tie direction is disposed at the upper portion of the end structure. A plurality of post reinforcement members are disposed in the vertical direction so as to stand on an end beam 26 of the underframe. The post reinforcement members and the upper reinforcement beam are respectively connected by an end post in the vertical direction disposed at an intermediate portion in the end structure width direction and corner posts 54 in the vertical direction disposed at both end portions in the end structure width direction.

Abstract: Provided is a railway vehicle having a configuration which can sufficiently protect the cabin even when large external force is applied to the side structures and the end structures thereof. The vehicle body of the railway vehicle is formed by joining an underframe 20, side structures 30, end structures 50, and a roof structure 60 together. The lower inner face of the side post 31 of the side structure is joined to the outer face portion of a side beam 21 of the underframe. The lower inner faces of the post reinforcement members (an end post reinforcement member 57 and a corner post reinforcement member 58) for reinforcing the post members (an end post 53 and a corner post 54) of the end structure are joined to the outer face portion of an end beam 26 of the underframe.

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: To provide a highly reliable inspection device that prevents a loss in reliability of inspection that uses information from a position detector as a result of the influence of magnetic bodies or the like that are present in the environment, the inspection device includes biological information measurement units that measure biological information of an inspected target and form an image containing the biological information, a magnetic position detector that detects the position of at least one of the biological information measurement units and the inspection target, and a control unit that controls the biological information measurement units and the magnetic position detector; and further includes the control unit being provided with an environmental magnetic field measurement unit that uses the output of the magnetic position detector to measure distortion of the magnetic field in the measured space in which the biological information measurement units are placed.

Abstract: Provided are a photodetector in which, in a III-V semiconductor having sensitivity in the near-infrared region to the far-infrared region, the carrier concentration can be controlled with high accuracy; an epitaxial wafer serving as a material of the photodetector; and a method for producing the epitaxial wafer. Included are a substrate formed of a III-V compound semiconductor; an absorption layer configured to absorb light; a window layer having a larger bandgap energy than the absorption layer; and a p-n junction positioned at least in the absorption layer, wherein the window layer has a surface having a root-mean-square surface roughness of 10 nm or more and 40 nm or less.

Abstract: A light-receiving element includes an InP substrate 1, a light-receiving layer 3 having an MQW and located on the InP substrate 1, a contact layer 5 located on the light-receiving layer 3, a p-type region 6 extending from a surface of the contact layer 5 to the light-receiving layer, and a p-side electrode 11 that forms an ohmic contact with the p-type region. The light-receiving element is characterized in that the MQW has a laminated structure including pairs of an InxGa1-xAs (0.38?x?0.68) layer and a GaAs1-ySby (0.25?y?0.73) layer, and in the GaAs1-ySby layer, the Sb content y in a portion on the InP substrate side is larger than the Sb content y in a portion on the opposite side.

Abstract: Provided is, for example, a photodiode in which extension of the sensitivity range to a longer wavelength in the near-infrared region can be achieved without increasing the dark current. A photodiode according to the present invention includes an absorption layer 3 that is positioned on an InP substrate 1 and has a type-II multiple-quantum well structure in which an InGaAs layer 3a and a GaAsSb layer 3b are alternately layered, wherein the InGaAs layer or the GaAsSb layer has a composition gradient in the thickness direction in which the bandgap energy of the InGaAs or the GaAsSb decreases toward the top surface or the bottom surface of the layer.

Abstract: An object of the present invention is to provide, for example, a photodiode that can have sufficiently high sensitivity in a near-infrared wavelength range of 1.5 ?m to 1.8 ?m and can have a low dark current. A photodiode (10) according to the present invention includes a buffer layer (2) positioned on and in contact with an InP substrate (1), and an absorption layer (3) positioned on and in contact with the buffer layer, wherein the absorption layer includes 50 or more pairs in which a first semiconductor layer 3a and a second semiconductor layer 3b constitute a single pair, the first semiconductor layer 3a having a bandgap energy of 0.73 eV or less, the second semiconductor layer 3b having a larger bandgap energy than the first semiconductor layer 3a, and the first semiconductor layer 3a and the second semiconductor layer 3b constitute a strain-compensated quantum well structure and each have a thickness of 1 nm or more and 10 nm or less.

Abstract: A method for manufacturing a semiconductor device, by which a multiple quantum well structure having a large number of pairs can be efficiently grown while maintaining good crystalline quality, and the semiconductor device, are provided. The semiconductor device manufacturing method of the present invention includes a step of forming a multiple quantum well structure 3 having 50 or more pairs of group III-V compound semiconductor quantum wells. In the step of forming the multiple quantum well structure 3, the multiple quantum well structure is formed by metal-organic vapor phase epitaxy using only metal-organic sources (all metal-organic source MOVPE).

Abstract: Provided is a railway vehicle having a configuration which can sufficiently protect the cabin even when large external force is applied to the side structures and the end structures thereof. The vehicle body of the railway vehicle is formed by joining an underframe 20, side structures 30, end structures 50, and a roof structure 60 together. The lower inner face of the side post 31 of the side structure is joined to the outer face portion of a side beam 21 of the underframe. The lower inner faces of the post reinforcement members (an end post reinforcement member 57 and a corner post reinforcement member 58) for reinforcing the post members (an end post 53 and a corner post 54) of the end structure are joined to the outer face portion of an end beam 26 of the underframe.

Abstract: Provided is a railway vehicle having a configuration which can sufficiently protect the cabin even when large external force is applied to the end structures thereof. An end structure 50 is disposed at an end portion of the vehicle body 11 through a crushable zone 40. The end structure is provided with an end post, corner posts, and an upper reinforcement beam 56. The lower end portions of the end post and the corner posts are joined to an end beam 26 of an underframe, and the upper end portions of the end post and the corner posts are joined to the upper reinforcement beam, respectively. In the crushable zone, there are provided a lower slide portion and an upper slide portion. The lower slide portion is configured by connecting a slide center beam projecting from a center portion of an end beam of the underframe in a direction of a cap beam with a guide center beam projecting from the cap beam in a vehicle end direction by a lower fuse member.

Abstract: Provided is a railway vehicle having a configuration which can sufficiently protect the cabin even when large external force is applied to the end structures thereof. The vehicle body of the railway vehicle is formed by joining an underframe 20, side structures 30, end structures 50, and a roof structure 60 together. An upper reinforcement beam 56 in the railroad tie direction is disposed at the upper portion of the end structure. A plurality of post reinforcement members are disposed in the vertical direction so as to stand on an end beam 26 of the underframe. The post reinforcement members and the upper reinforcement beam are respectively connected by an end post in the vertical direction disposed at an intermediate portion in the end structure width direction and corner posts 54 in the vertical direction disposed at both end portions in the end structure width direction.

Abstract: A photodetector and a method of manufacturing the photodetector are provided, in which variation in sensitivity is suppressed over the near-infrared region from the short wavelength side including 1.3 ?m to the long wavelength side. The photodetector includes, on an InP substrate, an absorption layer of a type II multiple quantum well structure comprising a repeated structure of a GaAsSb layer and an InGaAs layer, and has sensitivity in the near-infrared region including wavelengths of 1.3 ?m and 2.0 ?m. The ratio of the sensitivity at the wavelength of 1.3 ?m to the sensitivity at the wavelength of 2.0 ?m is not smaller than 0.5 but not larger than 1.6.

Abstract: A light-receiving element includes an InP substrate 1, a light-receiving layer 3 having an MQW and located on the InP substrate 1, a contact layer 5 located on the light-receiving layer 3, a p-type region 6 extending from a surface of the contact layer 5 to the light-receiving layer, and a p-side electrode 11 that forms an ohmic contact with the p-type region. The light-receiving element is characterized in that the MQW has a laminated structure including pairs of an InxGa1-xAs (0.38?x?0.68) layer and a GaAs1-ySby (0.25?y?0.73) layer, and in the GaAs1-ySby layer, the Sb content y in a portion on the InP substrate side is larger than the Sb content y in a portion on the opposite side.

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 1, and includes a pixel P. The photodiode includes an absorption layer 3 of a type II MQW structure, which is located on the substrate 1. The MQW structure includes fifty or more pairs of two different types of group III-V compound semiconductor layers 3a and 3b. The thickness of one of the two different types of group III-V compound semiconductor layers, which layer 3a has a higher potential of a valence band, is thinner than the thickness of the other layer 3b.

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: 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.