Abstract: Provided is a method for treating a group III nitride substrate capable of obtaining, in the case where a group III nitride layer is laminated thereon, a group III nitride substrate that can form an electronic device having excellent characteristics. The method for treating a group III nitride substrate includes the steps of CMPing a surface of a substrate, elevating a temperature of the group III nitride substrate after the CMP process to a predetermined annealing temperature under a nitrogen gas atmosphere, and holding the group III nitride substrate whose temperature has been elevated to the annealing temperature for four minutes or more and eight minutes or less in a first mixed atmosphere of a hydrogen gas and a nitrogen gas or a second mixed atmosphere of a hydrogen gas and an ammonia gas.

Abstract: Provided is a lattice-matched HEMT device, which is a HEMT device having high reverse breakdown voltage while securing two-dimensional electron gas concentration in a practical range. In producing a semiconductor device by forming a channel layer made of GaN on a base substrate such as an AlN template substrate or a substrate that includes a Si single crystal base material as a base, forming a barrier layer made of a group-III nitride having a composition of InxAlyGazN (x+y+z=1, 0?z?0.3) on the channel layer, and forming a source electrode, a drain electrode, and a gate electrode on the barrier layer, an In mole fraction x, a Ga mole fraction z, and a thickness d of the barrier layer satisfy a predetermined range.

Abstract: An epitaxial substrate, in which a group of group-III nitride layers is formed on a single-crystal silicon substrate so that a crystal plane is approximately parallel to a substrate surface, comprises: a first group-III nitride layer formed of AlN on the base substrate; a second group-III nitride layer formed of InxxAlyyGazzN (xx+yy+zz=1, 0?xx?1, 0<yy?1 and 0<zz?1) on the first group-III nitride layer; and at least one third group-III nitride layer epitaxially-formed on the second group-III nitride layer, wherein: the first group-III nitride layer is a layer containing multiple defects including at least one type of a columnar crystal, a granular crystal, a columnar domain and a granular domain; and an interface between the first group-III nitride layer and the second group-III nitride layer is a three-dimensional asperity surface.

Abstract: Provided is an epitaxial substrate for a semiconductor device, which has excellent schottky contact characteristics that are stable over time. The epitaxial substrate for a semiconductor device includes a base substrate, a channel layer formed of a first group III nitride containing at least Ga and having a composition of Inx1Aly1Gaz1N (x1+y1+z1=1), and a barrier layer formed of a second group III nitride containing at least In and Al and having a composition of Inx2Aly2Gaz2N (x2+y2+z2=1), wherein the barrier layer has tensile strains in an in-plane direction, and pits are formed on a surface of the barrier layer at a surface density of 5×107/cm2 or more and 1×109/cm2 or less.

Abstract: The motor-driven compressor is mounted on a mounting of a vehicle. The motor-driven compressor includes a compressor body, a mounting, a damper and a fastener. The compressor body is electrically powered to draw in fluid for compression and to discharge the compressed fluid. The mounting of the compressor is formed on the compressor body and has a mounting hole. The damper is made of a resin and receives therein the mounting of the compressor. The damper is interposed between the compressor body and the mounting of the vehicle and has a through hole. The fastener is inserted through the through hole of the damper and the mounting hole of the compressor for securing the damper to the mounting of the vehicle.

Abstract: Provided is a semiconductor device in which a reverse leakage current is suppressed and the mobility of a two-dimensional electron gas is high. A semiconductor device includes: an epitaxial substrate in which a group of group-III nitride layers are laminated on a base substrate such that a (0001) crystal plane is substantially in parallel with a substrate surface; and a Schottky electrode. The epitaxial substrate includes: a channel layer made of a first group-III nitride having a composition of Inx1Aly1Gaz1N (x1+y1+z1=1, z1>0); a barrier layer made of a second group-III nitride having a composition of Inx2Aly2N (x2+y2=1, x2>0, y2>0); an intermediate layer made of GaN adjacent to the barrier layer; and a cap layer made of AlN and adjacent to the intermediate layer. A Schottky electrode is bonded to the cap layer.

Abstract: Provided is an epitaxial substrate for semiconductor device that is capable of achieving a semiconductor device having high reliability in reverse characteristics of schottky junction. An epitaxial substrate for semiconductor device obtained by forming, on a base substrate, a group of group III nitride layers by lamination such that a (0001) crystal plane of each layer is approximately parallel to a substrate surface includes: a channel layer formed of a first group III nitride having a composition of Inx1Aly1Gaz1N (x1+y1+z1=1, z1>0); and a barrier layer formed of a second group III nitride having a composition of Inx2Aly2N (x2+y2=1, x2>0, y2>0), wherein the second group III nitride is a short-range-ordered mixed crystal having a short-range order parameter ? satisfying a range where 0???1.

Abstract: Provided is an epitaxial substrate capable of achieving a semiconductor device that has excellent schottky contact characteristics as well as satisfactory device characteristics. On a base substrate, a channel layer formed of a first group III nitride that contains at least Al and Ga and has a composition of Inx1Aly1Gaz1N (x1+y1+z1=1) is formed. On the channel layer, a barrier layer formed of a second group III nitride that contains at least In and Al and has a composition of Inx2Aly2Gaz2N (x2+y2+z2=1) is formed such that an In composition ratio of a near-surface portion is smaller than an In composition ratio of a portion other than the near-surface portion.

Abstract: Provided is an epitaxial substrate capable of achieving a semiconductor device that has excellent ohmic contact characteristics as well as satisfactory device characteristics. On a base substrate, a channel layer formed of a first group III nitride that contains at least Al and Ga and has a composition of Inx1Aly1Gaz1N (x1+y1+z1=1) is formed. On the channel layer, a barrier layer formed of a second group III nitride that contains at least In and Al and has a composition of Inx2Aly2Gaz2N (x2+y2+z2=1) is formed such that an In composition ratio of a near-surface portion is larger than an In composition ratio of a portion other than the near-surface portion.

Abstract: Provided is a crack-free epitaxial substrate with reduced warping, in which a silicon substrate is used as a base substrate. The epitaxial substrate includes a (111) single crystal Si substrate, a superlattice layer group in which a plurality of superlattice layers are laminated, and a crystal layer. The superlattice layer is formed of a first unit layer and a second unit layer made of group-III nitrides having different compositions being alternately and repeatedly laminated. The crystal layer is made of a group-III nitride and formed above the base substrate so as to be positioned at an upper side of the superlattice layer group relative to the base substrate. The superlattice layer group has a compressive strain contained therein. In the superlattice layer group, the more distant the superlattice layer is from the base substrate, the greater the compressive strain becomes.

Abstract: A semiconductor device is provided such that a reverse leak current is suppressed, and a Schottky junction is reinforced. The semiconductor device includes an epitaxial substrate formed by laminating a group of group-III nitride layers on a base substrate in such a manner that (0001) surfaces of said group-III nitride layers are substantially parallel to a substrate surface, and a Schottky electrode, in which the epitaxial substrate includes a channel layer formed of a first group-III nitride having a composition of Inx1Aly1Gaz1N, a barrier layer formed of a second group-III nitride having a composition of Inx2Aly2N, and a contact layer formed of a third group-III nitride having insularity and adjacent to the barrier layer, and the Schottky electrode is connected to the contact layer. In addition, a heat treatment is performed under a nitrogen atmosphere after the gate electrode has been formed.

Abstract: An epitaxial substrate, in which a group of group-III nitride layers is formed on a single-crystal silicon substrate so that a crystal plane is approximately parallel to a substrate surface, comprises: a first group-III nitride layer formed of AlN on the base substrate; a second group-III nitride layer formed of InxxAlyyGazzN (xx+yy+zz=1, 0?xx?1, 0<yy?1 and 0<zz?1) on the first group-III nitride layer; and at least one third group-III nitride layer epitaxially-formed on the second group-III nitride layer, wherein: the first group-III nitride layer is a layer containing multiple defects including at least one type of a columnar crystal, a granular crystal, a columnar domain and a granular domain; and an interface between the first group-III nitride layer and the second group-III nitride layer is a three-dimensional asperity surface.

Abstract: The motor-driven compressor is mounted on a mounting of a vehicle. The motor-driven compressor includes a compressor body, a mounting, a damper and a fastener. The compressor body is electrically powered to draw in fluid for compression and to discharge the compressed fluid. The mounting of the compressor is formed on the compressor body and has a mounting hole. The damper is made of a resin and receives therein the mounting of the compressor. The damper is interposed between the compressor body and the mounting of the vehicle and has a through hole. The fastener is inserted through the through hole of the damper and the mounting hole of the compressor for securing the damper to the mounting of the vehicle.

Abstract: Provided is an epitaxial substrate for semiconductor device that is capable of achieving a semiconductor device having high reliability in reverse characteristics of schottky junction. An epitaxial substrate for semiconductor device obtained by forming, on a base substrate, a group of group III nitride layers by lamination such that a (0001) crystal plane of each layer is approximately parallel to a substrate surface includes: a channel layer formed of a first group III nitride having a composition of Inx1Aly1Gaz1N (x1+y1+z1=1, z1>0); and a barrier layer formed of a second group III nitride having a composition of Inx2Aly2N (x2+y2=1, x2>0, y2>0), wherein the second group III nitride is a short-range-ordered mixed crystal having a short-range order parameter ? satisfying a range where 0???1.

Abstract: Provided is an epitaxial substrate capable of achieving a semiconductor device that has excellent schottky contact characteristics as well as satisfactory device characteristics. On a base substrate, a channel layer formed of a first group III nitride that contains at least Al and Ga and has a composition of Inx1Aly1Gaz1N (x1+y1+z1=1) is formed. On the channel layer, a barrier layer formed of a second group III nitride that contains at least In and Al and has a composition of Inx2Aly2Gaz2N (x2+y2+z2=1) is formed such that an In composition ratio of a near-surface portion is smaller than an In composition ratio of a portion other than the near-surface portion.

Abstract: Provided is an epitaxial substrate capable of achieving a semiconductor device that has excellent ohmic contact characteristics as well as satisfactory device characteristics. On a base substrate, a channel layer formed of a first group III nitride that contains at least Al and Ga and has a composition of Inx1Aly1Gaz1N (x1+y1+z1=1) is formed. On the channel layer, a barrier layer formed of a second group III nitride that contains at least In and Al and has a composition of Inx2Aly2Gaz2N (x2+y2+z2=1) is formed such that an In composition ratio of a near-surface portion is larger than an In composition ratio of a portion other than the near-surface portion.

Abstract: An electron-emitting apparatus includes an electron-emitting element having a lower electrode, a dielectric emitter section, upper electrodes having micro through holes, and a circuit for applying a drive voltage Vin between the lower and upper electrodes. The drive voltage is applied between the lower and upper electrodes to set an element voltage Vka, which is a potential of the upper electrode relative to a potential of the lower electrode, at a negative voltage for a charge accumulation period Td to accumulate electrons in the emitter section, and to set the element voltage Vka at a predetermined positive voltage for an electron emission period Th to emit electrons from the emitter section. The drive voltage applying circuit stepwise increases the positive voltage during the electron emission period Th and separately emits the electrons accumulated in the emitter section a plurality of times.

Abstract: An electron-emitting apparatus includes an electron-emitting element having a lower electrode, an emitter section having a dielectric material, and a plurality of upper electrodes having micro through holes, and a drive voltage applying circuit having a circuit for applying a drive voltage Vin between the lower electrode and the upper electrode. The drive voltage applying circuit applies a drive voltage between the lower electrode and the upper electrode to set an element voltage Vka, which is a potential of the upper electrode relative to a potential of the lower electrode, at a negative voltage for a charge accumulation period Td so as to accumulate electrons in the emitter section, and to set the element voltage Vka at a predetermined positive voltage for an electron emission period Th so as to emit electrons from the emitter section.

Abstract: A Plasmodium falciparum gene encoding immunogenic SERA protein has been isolated by a) systematically screening a lambda gt11 recombinant DNA expression library with a murine monoclonal antibody directed against protein antigens of this pathogen, and b) systematically screening a lambda gt11 genomic cDNA and oligonucleotide probes directed against this pathogen. A 111 kDa protein has been shown to have immunogenic activity against parasite inhibitory antibodies. The gene encoding this protein, including the signal sequence and regulatory sequence in the adjacent 5′ flanking sequence has been isolated and sequenced. Isolation and characterization of genes encoding major protein antigens of P. falciparum make it possible to develop reagents useful in the diagnosis, prevention and treatment of malaria. In addition, the signal sequences or regulatory sequences of this gene can be used to stimulate the production of other useful genetic products.