Abstract: A manufacturing method of a semiconductor apparatus including: setting, depending on a distribution of the carrier concentrations that the buffer region should have, a dose amount of hydrogen ions to be implanted into a plurality of depth positions corresponding to the plurality of concentration peaks; and implanting, depending on the dose amount that is set in the setting, the hydrogen ions into the semiconductor substrate is provided. In the setting, among the plurality of concentration peaks, the dose amount of the hydrogen ions for a deepest peak farthest from the lower surface of the semiconductor substrate is set depending on a carbon concentration of the semiconductor substrate, and the dose amount for at least one of the concentration peaks other than the deepest peak is set regardless of the carbon concentration of the semiconductor substrate.

Abstract: A method for manufacturing a nitride semiconductor device includes: selectively ion-implanting an element that is other than p-type impurities and n-type impurities into a first region in a first primary surface of a gallium nitride layer so as to generate crystal defects in the first region; selectively ion-implanting a p-type impurity into a second region in the gallium nitride layer, the second region being shallower than the first region in a depth direction and being within the first region in a plan view; and thermally treating said gallium nitride layer that has been ion-implanted with said element and said p-type impurity so as to thermally diffuse said p-type impurity in the second region into a third region that is within the first region and that surrounds a bottom and sides of the second region.

Abstract: A nitride semiconductor device is provided, comprising: a first nitride semiconductor layer of a first conductivity-type; a second nitride semiconductor layer of a second conductivity-type provided above the first nitride semiconductor layer; a junction region of a first conductivity-type which is provided to extend in a direction from a front surface of the second nitride semiconductor layer to the first nitride semiconductor layer and has a doping concentration NJFET equal to or higher than that of the first nitride semiconductor layer; and a source region of a first conductivity-type which is provided more shallowly than the junction region and has a doping concentration equal to or higher than the doping concentration NJFET, wherein a dopant of the source region is an element with an atomic weight larger than that of a dopant in the junction region.

Abstract: To provide a nitride semiconductor device excellent in switching characteristics. A nitride semiconductor device includes: a gallium nitride layer having a first principal surface and a second principal surface located on an opposite side to the first principal surface and having a trench formed from the first principal surface to the second principal surface side; and a field effect transistor formed in the gallium nitride layer, wherein the trench has a first side surface and a second side surface inside the trench, the first side surface is a nitrogen face in the surface layer of which nitrogen atoms are located, the second side surface is a gallium face in the surface layer of which gallium atoms are located, and the field effect transistor has: a gate insulating film formed on the first side surface; and a gate electrode formed in the trench and covering the gate insulating film.

Abstract: A nitride semiconductor device including: a gallium nitride substrate; and a vertical MOSFET provided on the gallium nitride substrate, the vertical MOSFET including: an N-type drift region provided in the gallium nitride substrate; a P-type well region provided in the drift region; an N-type source region provided in the well region; a gate insulating film provided on a surface of the well region; and a gate electrode provided on the surface of the well region via the gate insulating film, wherein the well region includes a first well region and a second well region higher in acceptor element concentration than the first well region, the second well region being located between the first well region and the gate insulating film and being in contact with the source region.

Abstract: A nitride semiconductor device includes a GaN-based semiconductor layer; and an insulating film provided on a first surface of the GaN-based semiconductor layer, the insulating film containing O atoms, and other constituent atoms other than O. An interface between the GaN-based semiconductor layer and the insulating film has a terminating species which terminates a dangling bond of a Ga atom, the terminating species has an outermost electron shell in which one electron is deficient from an allowed number of outermost electrons, and is an atom or molecule having stronger bond to the Ga atom than a H atom, an amount of Ga—O bonds is greater than an amount of bonds between the Ga atoms and the other constituent atoms.

Abstract: An impurity region of P-type that the field effect transistor of the nitride semiconductor device includes has a peak position at which concentration of P-type impurities reaches a maximum at a position located away from an interface with a gate insulating film. The impurity region has an inflection point at which concentration of the P-type impurities changes from increase to decrease toward the interface or a rate of decrease in the concentration of the P-type impurities increases toward the interface at a position located between the interface and the peak position.

Abstract: Provided is a radiation monitor and the like capable of appropriately measuring radiation. A radiation monitor (100) includes: radiation detection units (11, 12); optical fibers (13p, 13q) that transmit light generated by a plurality of radiation detection elements (11a, 12a) to merge; a light detection unit (14) that converts the light after merging guided to the light detection unit into an electric pulse; a measurement device (15) that calculates a dose rate of radiation based on a count rate of the electric pulses; and an analysis/display device (16). Housings (11b, 12b) include a housing (11b) made of a first material and another housing (12b) made of a second material.

Abstract: A radiation monitor includes a radiation detection unit detecting radiation, and an optical fiber transmitting photons emitted from a light emitting element of the radiation detection unit, wherein the radiation detection unit includes a first light emitting element generating a photon in response to incident radiation, a chemical compound part having chemical compounds which generate charged particles by nuclear reactions with incident neutrons, and a second light emitting element being located between the first light emitting element and the chemical compound part and generating a photon in response to radiation.

Abstract: A method for manufacturing a nitride semiconductor device including: forming N-type regions in a nitride semiconductor layer; implanting ions of an acceptor element into a region sandwiched by the N-type regions in the nitride semiconductor layer; and forming a P-type region sandwiched by the N-type regions by subjecting the nitride semiconductor layer to heat treatment and activating the acceptor element. The forming the N-type regions includes implanting ions of a donor element to the nitride semiconductor layer such that concentration of the donor element in the N-type regions is equal to or greater than concentration of the acceptor element in the P-type region. The implanting ions of the acceptor element includes implanting ions of the acceptor element such that concentration of the acceptor element in the P-type region is 1×1019 cm?3 or more and 1×1021 cm?3 or less.

Abstract: A method for manufacturing a nitride semiconductor device including: forming an N-type region in a nitride semiconductor layer; implanting ions of an acceptor element into a region under the N-type region in the nitride semiconductor layer; and forming a first P-type region under the N-type region by subjecting the nitride semiconductor layer to heat treatment and activating the acceptor element. The forming the N-type region includes implanting ions of a donor element into the nitride semiconductor layer such that concentration of the donor element in the N-type region is equal to or greater than concentration of the acceptor element in the first P-type region. The implanting ions of the acceptor element into a region under the N-type region includes implanting ions of the acceptor element such that concentration of the acceptor element in the first P-type region is 1×1019 cm?3 or more and 1×1021 cm?3 or less.

Abstract: A radiation monitoring device 1 includes a scintillator portion 10 which emits light whose intensity depends on a dose of incident radiation, an optical fiber 20 which transmits photons generated in the scintillator portion 10, a photoelectric converter 30 which converts photons transmitted by the optical fiber 20 to electric signals, a signal counter 40 which counts each of electric signals after being converted by the photoelectric converter 30 with a certain dead time adjusted relative to time width of an irradiation pulse of radiation, a dose calculation unit 50 which calculates a dose from a signal count value counted by the signal counter 40, and a display unit 60 which displays a result of measurement calculated by the dose calculation unit 50.

Abstract: A radiation monitoring device realizes a high measurement function. Therefore, a radiation monitoring device includes: a radiation detection unit including a phosphor that emits light by incident radiation; a photodetector that converts a single photon or a photon group having a plurality of the single photons generated by the radiation detection unit into an electric pulse signal; and an analysis unit that analyzes the electric pulse signal. The phosphor emits light based on a plurality of light emission phenomena having different decay time constants. The analysis unit includes: a signal discrimination circuit that discriminates the electric pulse signal output from the photodetector; a dose rate calculation circuit that calculates a dose rate of the radiation based on a count rate of the discriminated electric pulse signal; and an application energy calculation circuit that calculates application energy of the radiation based on a peak value of the discriminated electric pulse signal.

Abstract: A vertical MOSFET having a compound semiconductor layer is provided, the vertical MOSFET comprising a gate electrode, a gate insulating film provided between the gate electrode and the compound semiconductor layer, a drift region provided directly in contact with at least a part of the gate insulating film and being a part of the compound semiconductor layer, and a high resistance region provided at least in the drift region, is positioned below at least a part of the gate insulating film, and has a higher resistance value per unit length than that of the drift region.

Abstract: To provide a nitride semiconductor device excellent in switching characteristics. A nitride semiconductor device includes: a gallium nitride layer having a first principal surface and a second principal surface located on an opposite side to the first principal surface and having a trench formed from the first principal surface to the second principal surface side; and a field effect transistor formed in the gallium nitride layer, wherein the trench has a first side surface and a second side surface inside the trench, the first side surface is a nitrogen face in the surface layer of which nitrogen atoms are located, the second side surface is a gallium face in the surface layer of which gallium atoms are located, and the field effect transistor has: a gate insulating film formed on the first side surface; and a gate electrode formed in the trench and covering the gate insulating film.

Abstract: A nitride semiconductor device includes a nitride semiconductor layer, channel cells in the nitride semiconductor layer, a source lead region of a second conductivity type in the nitride semiconductor layer, and a source electrode on a side where a first main surface of the nitride semiconductor layer is located. The channel cells each include a well region of a first conductivity type and a source region of the second conductivity type in contact with the well region. The source lead region is connected to the source region. The channel cells extend in a first direction in a planar view from a normal direction of the first main surface, and arranged in a second direction intersecting with the first direction in the planar view. The source electrode is in contact with the source lead region away from a line of the channel cells arranged in the second direction.

Abstract: A gallium nitride based semiconductor device is provided, where when a thickness of a transition layer is defined as the followings, the thickness of the transition layer is less than 1.5 nm: (i) a distance between a depth position at which an atomic composition of nitrogen element constituting the gallium nitride based semiconductor layer is ½ relative to that at a position on the GaN based semiconductor layer side sufficiently away from the transition layer, and a depth position at which an atomic composition of a metal element is ½ of a value of a maximum if an atomic composition of the metal element constituting an insulating layer has the maximum, or a depth position at which an atomic composition of the metal element is ½ relative to that at a position on the insulating layer side sufficiently away from the transition layer if not having the maximum.

Abstract: A radiation monitor includes a radiation detection unit detecting radiation, and an optical fiber transmitting photons emitted from a light emitting element of the radiation detection unit, wherein the radiation detection unit includes a first light emitting element generating a photon in response to incident radiation, a chemical compound part having chemical compounds which generate charged particles by nuclear reactions with incident neutrons, and a second light emitting element being located between the first light emitting element and the chemical compound part and generating a photon in response to radiation.

Abstract: A screw compressor includes a screw rotor, a casing, and a fluid supply portion to supply fluid in a membrane form into a compression chamber in the casing. The screw rotor has a male and female rotors. A male bore covering the male rotor and a female bore covering the female rotor are formed on the inner surface of the casing. An intersection line, on a higher pressure side, of the male and female bores is defined as a compression cusp. In a bore development view, a trajectory made by the first intersection of an extension line of a female lobe ridge and a male lobe ridge being moved, along with the rotation of the male and female rotors, is defined as a trajectory line. An opening of the fluid supply section to the compression chamber is positioned between the compression cusp and the trajectory line.

Abstract: The nitride semiconductor device includes: a nitride semiconductor layer; a first conductivity type source region provided on a surface of the nitride semiconductor layer; a second conductivity type well region provided in the nitride semiconductor layer and adjacent to the source region in a first direction parallel to the surface and in a second direction intersecting with the first direction; a trench located on the opposite side of the source region with the well region sandwiched therebetween in the first direction; a first conductivity type impurity region located between the well region and the trench; an insulating film provided on a bottom surface of the trench; a gate insulating film provided on the well region; and a gate electrode provided from on the insulating film to on the gate insulating film. A thickness of the insulating film is larger than a thickness of the gate insulating film.