Abstract: A semiconductor laser outputs a laser light from an output facet of a waveguide having an index waveguide structure, via a lens system. The waveguide includes, in order from a rear facet opposite to the output facet, a first narrow portion, a wide portion that is wider than the first narrow portion, a second narrow portion narrower than the wide portion, a first tapered portion formed between the first narrow portion and the wide portion, which expands toward the wide portion, and a second tapered portion formed between the wide portion and the second narrow portion, which narrows toward the second narrow portion. Each of the first narrow portion, the wide portion, and the second narrow portion has a uniform width.

Abstract: A method of manufacturing a nitride substrate includes the following steps. Firstly, a nitride crystal is grown. Then, the nitride substrate including a front surface is cut from the nitride crystal. In the step of cutting, the nitride substrate is cut such that an off angle formed between an axis orthogonal to the front surface and an m-axis or an a-axis is greater than zero. When the nitride crystal is grown in a c-axis direction, in the step of cutting, the nitride substrate is cut from the nitride crystal along a flat plane which passes through a front surface and a rear surface of the nitride crystal and does not pass through a line segment connecting a center of a radius of curvature of the front surface with a center of a radius of curvature of the rear surface of the nitride crystal.

Abstract: A resin-made molded cylinder head cover, which is light in weight and relatively thin particularly at a flange part thereof comprises a cover part that is rectangular in shape and has a plurality of plug holes aligned in a longitudinally extending center area of the cover part; a flange part that is integral with and extends around a periphery of the cover part, so that the cylinder head cover is shaped like a rectangular shallow dish; and thicker elongate bead portions that are integral with the cover part and extend respectively along laterally opposed sides of the longitudinally extending center area, each bead portion being thicker than a general area of the cover part.

Abstract: A semiconductor laser outputs a laser light from an output facet of a waveguide having an index waveguide structure, via a lens system. The waveguide includes, in order from a rear facet opposite to the output facet, a first narrow portion, a wide portion that is wider than the first narrow portion, a second narrow portion narrower than the wide portion, a first tapered portion formed between the first narrow portion and the wide portion, which expands toward the wide portion, and a second tapered portion formed between the wide portion and the second narrow portion, which narrows toward the second narrow portion. Each of the first narrow portion, the wide portion, and the second narrow potion has a uniform width.

Abstract: A superconducting coil body and a superconducting device are provided so as to achieve reduction of loss. A superconducting coil body includes: an inner circumferential coil body serving as a coil main body portion in which a superconducting wire is wound; and a first magnetic body serving as a magnetic circuit member. The magnetic circuit member is formed of a magnetic body, and is disposed to face the upper surface of the inner circumferential coil body, the upper surface being positioned at an end surface side thereof crossing a main surface of the superconducting wire in the inner circumferential coil body. The first magnetic body is used to form a magnetic circuit for permitting magnetic flux, which is generated by a current flowing in the coil main body portion, to travel around the current.

Abstract: A mobile X-ray device 1 is provided with a main body 2 having an X-ray generating part 10 and an image reader 50 for reading X-ray image information from an imaging plate storing the X-ray image information, a running part 60 for running the main body 2, a battery 70 for storing direct current electrical energy to be supplied to the running part 60 and discharging a direct current at a rated voltage of the running part 60, and a direct current power source voltage conversion part 80 for transforming direct voltage of the battery 70 to a rated voltage of the image reader 50, wherein the rated voltage of the image reader 50 transformed by the direct current power source voltage conversion part 80 is applied to the image reader 50.

Abstract: A group III nitride semiconductor crystal substrate has a diameter of at least 25 mm and not more than 160 mm. The resistivity of the group III nitride semiconductor crystal substrate is at least 1×10?4 ?·cm and not more than 0.1 ?·cm. The resistivity distribution in the diameter direction of the group III nitride semiconductor crystal is at least ?30% and not more than 30%. The resistivity distribution in the thickness direction of the group III nitride semiconductor crystal is at least ?16% and not more than 16%.

Abstract: A method of producing an AlxGa(1-x)N (0<x?1) single crystal of the present invention is directed to growing an AlxGa(1-x)N single crystal by sublimation. The method includes the steps of preparing an underlying substrate, preparing a raw material of high purity, and growing an AlxGa(1-x)N single crystal on the underlying substrate by sublimating the raw material. At the AlxGa(1-x)N single crystal, the refractive index with respect to light at a wavelength greater than or equal to 250 nm and less than or equal to 300 nm is greater than or equal to 2.4, and the refractive index with respect to light at a wavelength greater than 300 nm and less than 350 nm is greater than or equal to 2.3, measured at 300K.

Abstract: A method of manufacturing a semiconductor element of good characteristics at a reduced manufacturing cost is provided. The manufacturing method of the semiconductor element includes a GaN-containing semiconductor layer forming step, an electrode layer forming step, a step of forming an Al film on the GaN-containing semiconductor layer, a step of forming a mask layer made of a material of which etching rate is smaller than that of a material of the Al film, a step of forming a ridge portion using the mask layer as a mask, a step of retreating a position of a side wall of the Al film with respect to a position of a side wall of the mask layer, a step of forming, on the side surface of the ridge portion and the top surface of the mask layer, a protective film made of a material of which etching rate is smaller than that of the material forming the Al film, and a step of removing the Al film and thereby removing the mask layer and a portion of the protective film formed on the top surface of the mask layer.

Abstract: A mobile X-ray device 1 is provided with a main body 2 having an X-ray generating part 10 and an image reader 50 for reading X-ray image information from an imaging plate storing the X-ray image information, a running part 60 for running the main body 2, a battery 70 for storing direct current electrical energy to be supplied to the running part 60 and discharging a direct current at a rated voltage of the running part 60, and a direct current power source voltage conversion part 80 for transforming direct voltage of the battery 70 to a rated voltage of the image reader 50, wherein the rated voltage of the image reader 50 transformed by the direct current power source voltage conversion part 80 is applied to the image reader 50.

Abstract: A semiconductor laser outputs a laser light from an output facet of a waveguide having an index waveguide structure, via a lens system. The waveguide includes, in order from a rear facet opposite to the output facet, a first narrow portion, a wide portion that is wider than the first narrow portion, a second narrow portion narrower than the wide portion, a first tapered portion formed between the first narrow portion and the wide portion, which expands toward the wide portion, and a second tapered portion formed between the wide portion and the second narrow portion, which narrows toward the second narrow portion. Each of the first narrow portion, the wide portion, and the second narrow potion has a uniform width.

Abstract: A method of manufacturing a nitride substrate includes the following steps. Firstly, a nitride crystal is grown. Then, the nitride substrate including a front surface is cut from the nitride crystal. In the step of cutting, the nitride substrate is cut such that an off angle formed between an axis orthogonal to the front surface and an m-axis or an a-axis is greater than zero. When the nitride crystal is grown in a c-axis direction, in the step of cutting, the nitride substrate is cut from the nitride crystal along a flat plane which passes through a front surface and a rear surface of the nitride crystal and does not pass through a line segment connecting a center of a radius of curvature of the front surface with a center of a radius of curvature of the rear surface of the nitride crystal.

Abstract: A method for manufacturing a semiconductor device according to the present invention includes the following step: a step (S10) of forming a GaN-based semiconductor layer, a step (S20) of forming an Al film on the GaN-based semiconductor layer, a step (S30, S40) of forming a mask layer composed of a material having a lower etching rate than that of the material constituting the Al film, a step (S50) of partially removing the Al film and the GaN-based semiconductor layer using the mask layer as a mask to form a ridge portion, a step (S60) of retracting the positions of the side walls at the ends of the Al film from the positions of the side walls of the mask layer, a step (S70) of forming a protection film composed of a material having a lower etching rate than that of the material constituting the Al film on the side surfaces of the ridge portion and on the upper surface of the mask layer, and a step (S80) of removing the Al film to remove the mask layer and the protection film formed on the upper surface of t

Abstract: A method for producing a group III-nitride crystal having a large thickness and high quality and a group III-nitride crystal are provided. A method for producing a group III-nitride crystal 13 includes the following steps: A underlying substrate 11 having a major surface 11a tilted toward the <1-100> direction with respect to the (0001) plane is prepared. The group III-nitride crystal 13 is grown by vapor-phase epitaxy on the major surface 11a of the underlying substrate 11. The major surface 11a of the underlying substrate 11 is preferably a plane tilted at an angle of ?5° to 5° from the {01-10} plane.

Abstract: A method of producing an AlxGa(1-x)N (0<x?1) single crystal of the present invention is directed to growing an AlxGa(1-x)N single crystal by sublimation. The method includes the steps of preparing an underlying substrate, preparing a raw material of high purity, and growing an AlxGa(1-x)N single crystal on the underlying substrate by sublimating the raw material. At the AlxGa(1-x)N single crystal, the refractive index with respect to light at a wavelength greater than or equal to 250 nm and less than or equal to 300 nm is greater than or equal to 2.4, and the refractive index with respect to light at a wavelength greater than 300 nm and less than 350 nm is greater than or equal to 2.3, measured at 300K.

Abstract: A method of producing an AlxGa(1-x)N (0<x?1) single crystal is directed to growing an AlxGa(1-x)N single crystal by sublimation. The method includes the steps of preparing an underlying substrate having a composition ratio x identical to the composition ratio of the AlxGa(1-x)N single crystal, preparing a raw material of high purity, and growing an AlxGa(1-x)N single crystal on the underlying substrate by sublimating the raw material. The AlxGa(1-x)N single crystal has an absorption coefficient less than or equal to 100 cm?1 with respect to light at a wavelength greater than or equal to 250 nm and less than 300 nm, and an absorption coefficient less than or equal to 21 cm?1 with respect to light at a wavelength greater than or equal to 300 nm and less than 350 nm.

Abstract: Affords an AlxGa1-xN single crystal suitable as an electromagnetic wave transmission body, and an electromagnetic wave transmission body that includes the AlxGa1-xN single crystals. The AlxGa1-xN (0<x?1) single crystal (2) has a dielectric loss tangent of 5×10?3 or lower with a radio frequency signal of at least either 1 MHz or 1 GHz having been applied to the crystal at an atmospheric temperature of 25° C. An electromagnetic wave transmission body (4) includes the AlxGa1-xN single crystal, which has a major surface (2m), wherein the AlxGa1-xN single crystal (2) has a dielectric loss tangent of 5×10?3 or lower with an RF signal of at least either 1 MHz or 1 GHz having been applied thereto at an atmospheric temperature of 25° C.

Abstract: A method of manufacturing a semiconductor element of good characteristics at a reduced manufacturing cost is provided. The manufacturing method of the semiconductor element includes a GaN-containing semiconductor layer forming step, an electrode layer forming step, a step of forming an Al film on the GaN-containing semiconductor layer, a step of forming a mask layer made of a material of which etching rate is smaller than that of a material of the Al film, a step of forming a ridge portion using the mask layer as a mask, a step of retreating a position of a side wall of the Al film with respect to a position of a side wall of the mask layer, a step of forming, on the side surface of the ridge portion and the top surface of the mask layer, a protective film made of a material of which etching rate is smaller than that of the material forming the Al film, and a step of removing the Al film and thereby removing the mask layer and a portion of the protective film formed on the top surface of the mask layer.

Abstract: A group III nitride semiconductor crystal substrate has a diameter of at least 25 mm and not more than 160 mm. The resistivity of the group III nitride semiconductor crystal substrate is at least 1×10?4 ?·cm and not more than 0.1 ?·cm. The resistivity distribution in the diameter direction of the group III nitride semiconductor crystal is at least ?30% and not more than 30%. The resistivity distribution in the thickness direction of the group III nitride semiconductor crystal is at least ?16% and not more than 16%.

Abstract: A method for manufacturing a semiconductor device according to the present invention includes the following step: a step (S10) of forming a GaN-based semiconductor layer, a step (S20) of forming an Al film on the GaN-based semiconductor layer, a step (S30, S40) of forming a mask layer composed of a material having a lower etching rate than that of the material constituting the Al film, a step (S50) of partially removing the Al film and the GaN-based semiconductor layer using the mask layer as a mask to form a ridge portion, a step (S60) of retracting the positions of the side walls at the ends of the Al film from the positions of the side walls of the mask layer, a step (S70) of forming a protection film composed of a material having a lower etching rate than that of the material constituting the Al film on the side surfaces of the ridge portion and on the upper surface of the mask layer, and a step (S80) of removing the Al film to remove the mask layer and the protection film formed on the upper surface of t