摘要:
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 characteristics, T.T.E. attenuation level, group delay time, etc.
摘要:
In a surface acoustic wave transducer including a substrate made of a piezoelectric material, an input side IDT structure having positive and negative electrodes arranged in an interdigit manner and floating electrodes arranged between successive positive and negative electrodes, and an output side IDT structure having positive and negative electrodes arranged in an interdigit manner and floating electrodes arranged between successive positive and negative electrodes, the electrodes of the input and output side IDT structures are arranged such that a surface acoustic wave propagates in one direction, distances between corresponding tracks in the input and output side IDT structures are linearly changed and lengths of these tracks are changed in accordance with a predetermined window function.
摘要:
A cooling member includes a heat-transfer member having a groove and a refrigerant introducing pipe pressed into the groove. The refrigerant introducing pipe has a pressed region positioned inwardly of the edge of the heat-transfer member, and at least one curbed surface portion. A method for manufacturing a cooling member includes preparing a punch having at least one curved corner and a pressing surface, positioning the corner, and moving the punch closer to the groove to press the refrigerant introducing pipe into the groove with the pressing surface. A device for manufacturing a cooling member includes the punch and a support configured to support the heat-transfer member so the groove is positioned opposite the punch.
摘要:
In an active matrix substrate (100) of the present invention, a gate bus line (105) and a gate electrode (166) extend in the first direction (the x direction). At a contact portion (168) for electrically connecting the gate bus line (105) with the drain regions of a first-conductivity-type transistor section (162) and a second-conductivity-type transistor section (164), the direction of the straight line (L1) of the shortest distance (d1) between one of a plurality of first-conductivity-type drain connecting portions (168c) that is closest to the gate bus line (105) and the gate bus line (105) is inclined with respect to the second direction (the y direction).
摘要:
A power module includes a power semiconductor, a non-power semiconductor, one resin substrate, and a cooling device. The power semiconductor and the non-power semiconductor configure a power supply circuit for performing power conversion. Both the power semiconductor and the non-power semiconductor are mounted on the resin substrate. The cooling device is disposed in order to cool the power semiconductor.
摘要:
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.
摘要:
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.
摘要:
A group III nitride underlayer including at least Al, having a dislocation density of ≦1×1011/cm2 and a (002) plane X-ray rocking curve half-width value of ≦200 seconds is formed on a set base material. A p-type semiconductor layer group is formed above the group III nitride underlayer and includes a group III nitride in which the Ga content relative to the total group III elements is ≧50% and in which a carrier density is ≧1×1016/cm3. A light-emitting layer is formed on the p-type semiconductor layer group and includes plural mutually isolated insular crystals. An n-type semiconductor layer group is formed on the light-emitting layer and includes a Ga content relative to the total group III elements of ≧50%.
摘要:
A base material made of C-faced sapphire single crystal is set on a susceptor installed in a reactor arranged horizontally. Then, a trimethyl-aluminum 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.
摘要:
An AlN film as an underlayer is epitaxially grown on a substrate having a dislocation density of 1011/cm2 or below and a crystallinity of 90 seconds or below in full width at half maximum (FWHM) of an X-ray rocking curve at (002) reflection. Then, on the AlN film an n-GaN film is epitaxially grown as a conductive layer having a dislocation density of 1010/cm2 or below and a crystallinity of 150 seconds or below in full width at half maximum (FWHM) of an X-ray rocking curve at (002) reflection, to fabricate a semiconductor element.
摘要翻译:将作为底层的AlN膜外延生长在具有10 11 / cm 2以下的位错密度和90秒以下的结晶度的X射线的半峰全宽(FWHM)的基板上 (002)反射的摇摆曲线。 然后,在AlN膜上,将n-GaN膜外延生长为位错密度为10 10 / cm 2以下的导电层,在半高宽度下为150秒以下的结晶度(FWHM )(002)反射的X射线摇摆曲线,以制造半导体元件。