Abstract: Provided is an epitaxial substrate capable of manufacturing a HEMT device that has excellent two-dimensional electron gas characteristics and is capable of performing normally-off operation. A channel layer is formed of a first group III nitride represented by Inx1Aly1Gaz1N (x1+y1+z1=1) so as to have a composition in a range determined by x1=0 and 0?y1?0.3. A barrier layer is formed of a second group III nitride represented by Inx2Aly2Gaz2N (x2+y2+z2=1) so as to have a composition, in a ternary phase diagram with InN, AlN and GaN being vertices, in a range surrounded by four straight lines determined in accordance with the composition (AlN molar fraction) of the first group III nitride and to have a thickness of 5 nm or less.

Abstract: Provided is an epitaxial substrate having excellent two-dimensional electron gas characteristics and reduced internal stress due to strains. A channel layer is formed of a first group III nitride represented by Inx1Aly1Gaz1N (x1+y1+z1=1) so as to have a composition in a range determined by x1=0 and 0?y1?0.3. A barrier layer is formed of a second group III nitride represented by Inx2Aly2Gaz2N (x2+y2+z2=1) so as to have a composition, in a ternary phase diagram with InN, AlN and GaN being vertices, in a range surrounded by five straight lines determined in accordance with the composition (AlN molar fraction) of the first group III nitride.

Abstract: An epitaxial substrate having preferable two dimensional electron gas characteristic and contact characteristic is provided in the present invention. A channel layer is formed on a base substrate with GaN. A spacer layer is formed on the channel layer with AlN. A barrier layer is formed on the spacer layer with group III nitride having a composition of InXAlyGazN (wherein x+y+z=1) and at least including In, Al, and Ga such that the composition of the barrier layer is within the range surrounded with four lines defined in accordance with the composition on a ternary phase diagram with InN, AlN, and GaN as vertexes.

Abstract: An underlying film 2 of a group III nitride is formed on a substrate 1 by vapor phase deposition. The substrate 1 and the underlying film 2 are subjected to heat treatment in the present of hydrogen to remove the underlying film 2 so that the surface of the substrate 1 is roughened. A seed crystal film 4 of a group III nitride single crystal is formed on a surface of a substrate 1A by vapor phase deposition. A group III nitride single crystal 5 is grown on the seed crystal film 4 by flux method.

Abstract: Provided is a light-receiving device which has light-receiving sensitivity superior to that of a conventional Schottky diode type light-receiving device and also has sufficiently-strengthened junction of a Schottky electrode. A first contact layer formed of AlGaN and having conductivity, a light-receiving layer formed of AlGaN, and a second contact layer formed of AlN and having a thickness of 5 nm are epitaxially formed on a predetermined substrate in the stated order, and a second electrode is brought into Schottky junction with the second contact layer, to thereby form MIS junction. Further, after the Schottky junction, heat treatment is performed under a nitrogen gas atmosphere at 600° C. for 30 seconds.

Abstract: A buffer layer formed of Inx1Aly1Gaz1N formed on a base, with an upper part of the buffer layer containing columnar polycrystalline including a grain boundary existing in a direction substantially perpendicular to a surface of the base. The number of grain boundaries in the lower part of the buffer layer is greater than that in the upper part, and a full width at half maximum of an X-ray rocking curve of the upper part is 300-3000 seconds, RMS of the surface of the buffer layer is 0.2 nm-6 nm, and the ratio of the grain boundary width of the crystal grain of the upper part in a direction parallel to the base surface to the formation thickness of the buffer layer is 0.5-1.5.

Abstract: A module is configured to be attached to a cage. A handle is rotatable about a rotation shaft between an accommodated position where the module is mounted to the cage and a withdrawal position where the module can be withdrawn from the cage. A resiliently-bendable tongue piece performs engagement and disengagement between the module and the cage. A notch portion is provided to the tongue piece. A press portion is provided to the handle on a circumference having a center located on the rotation shaft of the handle, the press portion configured to contact with the notch portion when the handle is at the accommodated position. A cam rotatable with the handle so as to resiliently bend the tongue piece.

Abstract: An optical module includes a housing including a groove part formed inside the housing; and a receptacle received in the housing, the receptacle to which an optical connector having an optical fiber is connected, the receptacle including a brim part and a stub part where the brim part is formed in a body. An elastic body is provided in the groove part, the groove part where the brim part is provided. The elastic body is configured to adhere to and hold the stub part.

Abstract: An optical module which can be inserted into and removed from a cage, the optical module includes a lock pin inserted into a lock hole provided in the cage and engaging the cage and the optical module with each other in a state where the optical module is inserted into the cage; a tongue having an axial part and configured to be rotated with respect to the axial part in a direction where the insertion of the lock pin into the lock hole is released; and a bail configured to be rotated with respect to a rotational axel so that the tongue is rotated. The engagement of the cage and the optical module formed by insertion of the lock pin into the lock hole is released by rotating the bail 90 degrees.

Abstract: A host apparatus of a financial auction system is disposed in a site that is accessible from user terminal apparatuses through the transmission line of a network. The host apparatus has a borrowing agent serving as the window for a potential borrower, a lending agent serving as the window for a potential lender, a screening section for extracting a potential lending offer matching a predetermined condition, a matchmaking section for selecting a successful bid from potential lending offers, and an information collection section for collecting background information of a potential borrowing request. A database is attached to the host apparatus, where a borrowing request file, lending offer file, and background information file are formed.

Abstract: An aspect of the present invention provides a magnetic sensor which is operated better at a high temperature range not lower than 300° C. compared with a conventional magnetic sensor. A operating layer having a heterojunction interface is formed by laminating a first layer made of GaN whose electron concentration is not more than 1×1016/cm3 at room temperature and a second layer made of AlxGa1-xN (0<x?0.3). Therefore, in a two-dimensional electron gas region, carrier mobility is further enhanced while a carrier concentration is further lowered. Accordingly, there is realized a Hall element which can be used with measurement sensitivity similar to that at room temperature by constant-current drive even at a high temperature, while having the high measurement sensitivity in both the constant-current drive and constant-voltage drive at room temperature.

Abstract: A normally-off operation type HEMT device excellent in characteristics can be realized. A two-dimensional electron gas region is formed in a periphery of a hetero-junction interface of a base layer and a barrier layer, so that access resistance in an access portion, that is, between a drain and a gate and between a gate and a source is sufficiently lowered, and at the same time, a P-type region is formed immediately under the gate. This realizes a normally-off type HEMT device having a low on-resistance. Further, when a film thickness of an insulating layer is defined as t (nm) and a relative permittivity of a substance forming the insulating layer is defined as k, a threshold voltage as high as +3 V or more can be attained by satisfying k/t?0.85 (nm?1).

Abstract: An optical module which can be inserted into and removed from a cage, the optical module includes a lock pin inserted into a lock hole provided in the cage and engaging the cage and the optical module with each other in a state where the optical module is inserted into the cage; a tongue having an axial part and configured to be rotated with respect to the axial part in a direction where the insertion of the lock pin into the lock hole is released; and a bail configured to be rotated with respect to a rotational axel so that the tongue is rotated. The engagement of the cage and the optical module formed by insertion of the lock pin into the lock hole is released by rotating the bail 90 degrees.

Abstract: A module is configured to be attached to a cage. A handle is rotatable about a rotation shaft between an accommodated position where the module is mounted to the cage and a withdrawal position where the module can be withdrawn from the cage. A resiliently-bendable tongue piece performs engagement and disengagement between the module and the cage. A notch portion is provided to the tongue piece. A press portion is provided to the handle on a circumference having a center located on the rotation shaft of the handle, the press portion configured to contact with the notch portion when the handle is at the accommodated position. A cam rotatable with the handle so as to resiliently bend the tongue piece.

Abstract: An optical receptacle includes a fiber stub; and a sleeve having a sleeve main body where the fiber stub is installed, the sleeve supported by a supporting surface of a supporting member. In the optical receptacle, a leaning prevention member is provided at the sleeve; the leaning prevention member is formed so as to extend outward from the sleeve main body; and the leaning prevention member prevents leaning of the sleeve main body from the supporting surface by coming in contact with the supporting surface.

Abstract: A semiconductor device made of a group-III nitride semiconductor having excellent properties is provided. The semiconductor device has a horizontal diode structure of Schottky type or P—N junction type, or combined type thereof having a main conduction pathway in the horizontal direction in a conductive layer with unit anode portions and unit cathode electrodes being integrated adjacently to each other in the horizontal direction. The conductive layer is preferably formed by depositing a group-III nitride layer and generating a two-dimensional electron gas layer on the interface. Forming the conductive layer of the group-III nitride having high breakdown field allows the breakdown voltage to be kept high while the gap between electrodes is narrow, which achieves a semiconductor device having high output current per chip area.

Abstract: A semiconductor device having small leakage current and high breakdown voltage during reverse blocking, small on-state resistance and large output current at forward conduction, short reverse recovery time at shutoff, and high peak surge current value is provided. An n-type layer is made of a group-III nitride, and a p-type layer is made of a group-IV semiconductor material having a smaller band gap than the group-III nitride. The energy level at the top of the valence band of the n-type layer is lower than the energy level at the top of the valence band of the p-type layer, so that a P—N junction semiconductor device satisfying the above requirements is obtained. Further, a combined structure of P—N junction and Schottky junction by additionally providing an anode electrode to be in Schottky contact with the n-type layer also achieves the effect of decreasing voltage at the rising edge of current resulting from the Schottky junction.

Abstract: A case containing an optical interface section including a connector-fitting unit in its front portion, a printed board in its central portion, and an electrical interface section in its rear portion is accommodated in a housing. When a data link module is inserted in a cage, a housing tongue and a through hole both formed in a bottom plate of the housing are overlapped with a cage tongue and a lock pin both provided in and on a bottom plate of the cage, into and from which the data link module is inserted and removed, such that the lock pin is engaged in and locked by the lock hole. When removing the data link module from the cage, by angularly turning a bail pivotally supported by the connector-fitting unit, the cage tongue is pushed down following to the housing tongue with the camming operation of a plate cam, thus causing the lock hole to be disengaged from the lock pin.

Abstract: A semiconductor device includes an underlying layer made of a group-III nitride containing at least Al and formed on a substrate, and a group of stacked semiconductor layers including a first semiconductor layer made of a group-III nitride, preferably GaN, a second semiconductor layer made of AlN and a third semiconductor layer made of a group-III nitride containing at least Al, preferably AlxGa1-xN where x?0.2. The semiconductor device suppresses the reduction in electron mobility resulting from lattice defects and crystal lattice randomness. This achieves a HEMT device having a sheet carrier density of not less than 1×1013/cm2 and an electron mobility of not less than 20000 cm2/V·s at a temperature of 15 K.

Abstract: A method for manufacturing a nitride film including a high-resistivity GaN layer includes a step of allowing a Group-III source gas containing an organic metal compound, a Group-V source gas containing ammonia, a carrier gas for the Group-III source gas, and a carrier gas for the Group-V source gas to flow over a predetermined monocrystalline wafer maintained at 1,000° C. or more and also includes a step of epitaxially growing a nitride film, including a GaN layer, on the monocrystalline wafer by a vapor phase reaction of the source gases. At least one of the carrier gases contains nitrogen while the wafer temperature is being increased before the reaction is carried out. At least one of the carrier gases contains hydrogen and nitrogen and has a total hydrogen and nitrogen content of 90 percent by volume or more in at least one part of the epitaxially growing step.