摘要:
In a transistor, an AlN buffer layer 102, an undoped GaN layer 103, an undoped AlGaN layer 104, a p-type control layer 105, and a p-type contact layer 106 are formed in this order on a sapphire substrate 101. The transistor further includes a gate electrode 110 in ohmic contact with the p-type contact layer 106, and a source electrode 108 and a drain electrode 109 provided on the undoped AlGaN layer 104. By applying a positive voltage to the p-type control layer 105, holes are injected into a channel to increase a current flowing in the channel.
摘要:
A method of manufacturing a cylindrical member having anti-slip projections formed on axial end faces, the method comprising the steps of: employing a roller die, which is provided with a circumferential die groove of annular form extending through a medial section in a generatrix direction of a die face defined by an integral tapered outside peripheral face, and with a plurality of sloping die grooves extending in a tapered slope direction of the die face situated to both large-diameter and small-diameter sides of the circumferential die groove; providing plastic working to the axial end face with the small-diameter side of the roller die facing towards an inner peripheral side of the cylindrical member and with the large-diameter side facing towards an outer peripheral side, by pushing the die face against the axial end face while rotating circumferentially; and forming simultaneously an annular water barrier projection and the anti-slip projections.
摘要:
A nitride semiconductor device includes: a first semiconductor layer made of first nitride semiconductor; a second semiconductor layer formed on a principal surface of the first semiconductor layer and made of second nitride semiconductor having a bandgap wider than that of the first nitride semiconductor; a control layer selectively formed on, or above, an upper portion of the second semiconductor layer and made of third nitride semiconductor having a p-type conductivity; source and drain electrodes formed on the second semiconductor layer at respective sides of the control layer; a gate electrode formed on the control layer; and a fourth semiconductor layer formed on a surface of the first semiconductor layer opposite to the principal surface, having a potential barrier in a valence band with respect to the first nitride semiconductor and made of fourth nitride semiconductor containing aluminum.
摘要:
A semiconductor light source includes a light-emitting device 101 having a plurality of semiconductor layers made of nitride semiconductors, and a drive circuit 102 for driving the light-emitting device 101. The drive circuit 102 performs forward drive operation, in which a forward current is supplied to the light-emitting device to make the light-emitting device 101 emit light, and reverse drive operation, in which a reverse bias is applied to the light-emitting device. The magnitude of the reverse bias is limited by the value of a reverse current flowing through the light-emitting device.
摘要:
An optical information recording medium includes a recording layer in which a recording mark formed of a cavity is formed in accordance with a light for recording, and which contains therein a compound having a skeleton expressed by the general formula (1): where R1, R2, R3, and R4 are either hydrogen atoms or substituents.
摘要:
A semiconductor laser (101) includes a first cladding layer (103), an active layer (105) and a second cladding layer (108). A window region (115) including fluorine, that is, an impurity element with higher electronegativity than nitrogen, is formed in the vicinity of a front end face (113) and a rear end face (114) of a laser resonator. The window region (115) is formed by exposing the front end face (113) and the rear end face (114) to carbon fluoride (CF4) plasma. The effective band gap of a portion of the active layer (105) disposed in the window region (115) is larger than the effective band gap of another portion of the active layer, and hence, it functions as an end face window structure for suppressing COD.
摘要:
A sheet feeding device, having: a sheet feeding tray which stacks a paper sheet bundle formed by a plurality of sheets; a first blower which blows air to a side edge of the paper sheet bundle stacked on the sheet feeding tray; a second blower which blows air to a leading edge of the paper sheet bundle in a sheet conveyance direction from a forward side of the paper sheet bundle in the sheet conveyance direction; and an adsorption conveyance section which adsorbs a topmost sheet of the paper sheet bundle stacked on the sheet feeding tray and conveys the topmost sheet, wherein a first area in which the adsorption conveyance section is provided, and a second area in which a ventilation port of the first blower is provided, respectively includes an overlapping area in which the first area and the second area overlap on the sheet conveyance direction.
摘要:
An acoustic resonator includes: a substrate; a resonator film which is supported above the main surface of the substrate and includes a piezoelectric film and a pair of a top electrode and a bottom electrode which are formed on part of the top surface and part of the bottom surface of the piezoelectric film, respectively, to face each other via the piezoelectric film; and a support which is formed on the main surface of the substrate to support the resonator film from below. A resonance cavity is provided in part of a region between the substrate and the resonator film below at least a portion of part of the resonator film where the top electrode and the bottom electrode coincide with each other and an isolation cavity is provided in other part of said region where the support and the resonance cavity do not exist.
摘要:
A nitride semiconductor device includes a semiconductor stacked structure which is formed of a nitride semiconductor having a first principal surface and a second principal surface opposed to the first principal surface and which includes an active layer. The first principal surface of the semiconductor stacked structure is formed with a plurality of indentations whose plane orientations are the {0001} plane, and the plane orientation of the second principal surface is the {1-101} plane. The active layer is formed along the {1-101} plane.
摘要:
A surface emitting laser includes a plurality of light-emitting portions for emitting laser light beams in different linearly polarized light directions. The light-emitting portions are formed on the substrate and located close to each other. The light-emitting portions include metal opening arrays through which light beams in different linearly polarized light directions respectively pass.