Abstract: In a semiconductor light-emitting element, an underlayer is composed of a high crystallinity AlN layer having a FWHM in X-ray rocking curve of 90 seconds or below, and a first cladding layer is composed of an n-AlGaN layer. A light-emitting layer is composed of a base layer made of i-GaN and plural island-shaped single crystal portions made of i-AlGaInN isolated in the base layer.

Abstract: In a semiconductor light-emitting element, an underlayer is made of AlN layer, and a first cladding layer is made of an n-AlGaN layer. A light-emitting layer is composed of a base layer made of i-GaN and plural island-shaped single crystal portions made of i-AlGaInN isolated in the base layer. Then, at least one rare earth metal element is incorporated into the base layer and/or the island-shaped single crystal portions.

Abstract: A III nitride buffer film including at least Al element and having a screw-type dislocation density of 1×108/cm2 or below is formed on a base made of a sapphire single crystal, etc., to fabricate an epitaxial base substrate. Then, a III nitride underfilm is formed on the III nitride buffer film, to fabricate an epitaxial substrate.

Abstract: At least one of the interior wall of a reactor and a susceptor installed in the reactor is coated with an AlaGabIncN (a+b+c=1, a>0) film, which is heated to about 1000° C. or over when a substrate is heated to a predetermined temperature so as to generate the MOCVD reaction between a III raw material gas and a V raw material gas. Therefore, the AlpGaqInrN (p+q+r=1) compound generated from the raw material gases is deposited on the coated AlaGablncN (a+b+c=1, a>0) film, and thus, particles composed of the AlpGaqlnrN compound are not almost created. As a result, the resulting AlxGaylnzN (x+y+z=1) film is not affected by the particles, and can have its desirable quality.

Abstract: A III nitride film is directly grown on a crystalline substrate along the C-axis, and includes at least Al element. Then, the III nitride film has hexagonal crystal system, and the lattice constant “c” of the main axis and the lattice constant “a” of the crystal face perpendicular to the main surface satisfies the relation of “C>2.363a-3.232”.

Abstract: A base material made of C-faced sapphire single crystal is set on a susceptor installed in a reactor arranged horizontally. Then, a trimethylaluminum and an ammonia are introduced as raw material gases into the reactor and supplied onto the substrate, to form an AlN film. In this case, the temperature of the base material is set to 1100° C. or over, and the ratio (V raw material gas/III raw material gas) is set to 800 or below, and the forming pressure is set within a range of 7-17 Torr. As a result, the crystallinity of the AlN film is developed to 90 arcsec or below in FWHM of X-ray rocking curve, and the surface flatness of the AlN film is developed to 20 Å or below. Therefore, a substrate composed of the base material and the AlN film is preferably usable for an acoustic surface wave device, and if the substrate is employed, the deviation from the theoretical propagation velocity is set to 1.5 m/sec or below.

Abstract: A III nitride film including Al element is fabricated by a MOCVD method with monitoring the dew point of the reactor to be used in the MOCVD method. An organic metal vapor flown in the reactor, the dew point is preferably set to a temperature of −90° C. or below. Then, the film is fabricated.

Abstract: An epitaxial wafer has a base material made of sapphire-SiC single crystal or the like, a III nitride underfilm including at least Al element epitaxially grown on the base material and a GaN film, preferably having a thickness of 50 Å or over, formed on the underfilm. In a fabricating a III nitride films on the epitaxial wafer, the oxidized surface layer of the GaN film is removed through etching process, and subsequently, the III nitride film is formed.

Abstract: In order to provide a transducer suitable for an anisotropic substrate having the NSPUDT property, on the anisotropic piezoelectric substrate being cut to have the NSPUDT property, there is formed a transducer structure having an exciting electrode structure (21) and a reflector structure (22). When &lgr; is a wavelength of a fundamental surface acoustic wave, said exciting electrode structure (21) includes a positive electrode (23) having a plurality of electrode fingers arranged at a pitch &lgr; and a negative electrode (24) having at least one electrode finger interdigitally arranged between said electrode fingers of the positive electrode with a center distance of &lgr;/2. The reflector transducer (22) includes a plurality of electrode fingers arranged with a center distance of &lgr;/2, and a distance Lg between said exciting electrode structure (21) and the reflector structure (22) is set to Lg=(2n+1)&lgr;/4 (n being a positive integer).

Abstract: A semiconductor device has a substrate body, an AlxGayInzN (x+y+z=1,x,y,z≧0) film epitaxially grown direct on the substrate body or epitaxially grown via a buffer layer on the substrate body, and a metal film provided on the rear surface of the substrate body. In the case of the manufacturing the semiconductor device, the substrate body is heated, by a heater, uniformly and efficiently through the thermal radiation of the heater.

Abstract: A hydrogen chloride gas and an ammonia gas are introduced with a carrier gas into a reactor in which a substrate and at least an aluminum metallic material through conduits. Then, the hydrogen gas and the ammonia gas are heated by heaters, and thus, a III-V nitride film including at least Al element is epitaxially grown on the substrate by using a Hydride Vapor Phase Epitaxy method. The whole of the reactor is made of an aluminum nitride material which does not suffer from the corrosion of an aluminum chloride gas generated by the reaction of an aluminum metallic material with a hydrogen chloride gas.

Abstract: A buffer layer with a composition of AlaGabIncN (a+b+c=1, a, b, c≧0) and a multilayered thin films with a composition of AlxGayInzN (x+y+z=1, x, y, z≧0) are formed in turn on a substrate. The Al component of the Al component-minimum portion of the buffer layer is set to be larger than that of at least the thickest layer of the multilayered thin films. The Al component of the buffer layer is decreased continuously or stepwise from the side of the substrate to the side of the multilayered thin films therein.

Abstract: An object of the invention is to provide a light reflective film which can prevent moire fringes from occurring. A rough face in which a plurality of rows of pyramidal convex portions that are linearly continuous are adjacently formed in parallel with one another is formed on one face of a die film. The rows of convex portions that are linearly continuous are inclined at a predetermined angle with respect to an edge of the die film. An optical film is produced by transferring the die film. A light reflective film is produced by vapor-depositing a light reflection film on the optical film. In a liquid crystal display panel having the light reflective film, the pitch of occurring moire fringes becomes so small that the moire fringes cannot be visually seen, and moire fringes can be prevented from occurring.

Abstract: An elastomer composition which comprises: (a) 100 parts by weight of a hydrogenated block copolymer prepared by hydrogenating a block copolymer that comprises: a polymer block A mainly comprising at least one vinyl aromatic compound; and a polymer block B mainly comprising at least one conjugate diene, and has a number average molecular weight of from 30,000 to 400,000 and a content of the polymer block A of from 10 to 50% by weight based on the weight of said block copolymer; (b) 5 to 900 parts by weight of a polypropylene mixture comprising: (b-1) 10 to 60% by weight of a polypropylene polymer having a propylene content of 85% by weight or more; and (b-2) 40 to 90% by weight of an ethylene-propylene copolymer rubber having a propylene content of 75% by weight or more, wherein the ethylene-propylene copolymer rubber in said mixture has an average dispersed particle size of not more than 2 &mgr;m and said mixture has a bending modulus of from 20 to 700 Mpa, a Shore D hardness of from 20 to 60 and a melt flow

Abstract: A surface acoustic wave device including a substrate and an electrode structure formed on the substrate, said substrate being made of an X-cut Langasite single crystal, a rotation Y-cut Langasite single crystal or a double rotation Y-cut Langasite single crystal. When the X-cut Langasite crystal having a large reflection coefficient is used, the electrode structure is formed to constitute a surface acoustic wave resonator. When the rotation Y-cut Langasite crystal having a large electro-mechanical coupling coefficient and a small reflection coefficient is used, the electrode structure is formed to constitute a surface acoustic wave filter. When the double rotation Y-cut Langasite crystal having an NSPUDT property is used, the electrode structure is formed to constitute a surface acoustic wave filter having a low insertion loss and an excellent phase property.

Abstract: The object of the present invention is to offer a steering valve device which can reduce both space of the valve assembly in the vehicle and increment of cost and time for manufacturing the device.

Abstract: A surface acoustic wave matched filter for use in a spread spectrum communication system is disclosed. The surface acoustic wave matched filter includes a substrate having dispersity and is composed of a sapphire main body and a piezoelectric aluminum nitride. A tap distance L of an output side electrode is designed on the basis of a group velocity vg instead of a phase velocity vs in order to match the tap distance L with an input spread spectrum signal and to improve a correlation peak level of an output demodulated signal. When the tap distance L is set to satisfy a condition of vg/f1×0.97≦L≦vg/f1×1.02, a decrease in the correlation peak level of the matched filter can be improved from 7 dB to a value smaller than 3 dB, and S/N of the output demodulated signal can be increased. Thus, the disclosed device renders it no longer necessary to process the output demodulated signal by a complicated and power consuming circuit.

Abstract: A surface acoustic wave device including a substrate and an electrode structure formed on the substrate, said substrate being made of a doubly rotated Y-cut (&agr;X-&thgr;Y cut) Langasite (La3Ga5SiO14), a rotation angle &agr; from the X axis being substantially 50°±5° and a rotation angle &thgr; from the Y axis being substantially 19°-30°. The device further includes a normal type electrode structure which reveals a natural single-phase unidirectional transducer property together with an anisotropy of the substrate. The device further has a double electrode type electrode structure which cancels the directionality, or a floating type electrode structure which reverses the directionality. The electrode structure is formed to constitute a surface acoustic wave filter having a low insertion loss and an excellent phase property.

Abstract: An elastomer composition which comprises (a) 100 parts by weight of a hydrogenated block copolymer mixture comprising: (a-1) 10 to 60 parts by weight of a block copolymer prepared by hydrogenating a block copolymer that comprises: at least two polymer blocks A each mainly comprising a vinyl aromatic compound; and at least one polymer block B mainly comprising a conjugated diene compound, the hydrogenated block copolymer having a number average molecular weight of from more than 200,000 to not more than 400,000 and a content of the polymer block A of from 15 to 40% by weight of said block copolymer; and (a-2) 40 to 90 parts by weight of a block copolymer prepared by hydrogenating a block copolymer that comprises: at least one polymer block A mainly comprising a vinyl aromatic compound; and at least one polymer block B mainly comprising a conjugated diene compound, the hydrogenating block copolymer having a number average molecular weight of from more than 30,000 to not more than 140,000 and a content of the po

Abstract: A surface acoustic wave filter device suitable for CDMA communication system includes a piezoelectric substrate, and a unidirectional input side transducer and a bidirectional output side transducer are formed on the substrate. The filter device has satisfactory filtering characteristics in terms of insertion loss, frequency characteristic, T.T.E. attenuation level, group delay time, etc.