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Koji Katayama

Koji Katayama, Nara JP

Patent application numberDescriptionPublished
20090283736NONVOLATILE MEMORY ELEMENT, MANUFACTURING METHOD THEREOF, AND NONVOLATILE SEMICONDUCTOR APPARATUS USING THE NONVOLATILE MEMORY ELEMENT - A nonvolatile memory element comprises a first electrode layer (11-19-2009
20100271860DRIVING METHOD OF VARIABLE RESISTANCE ELEMENT, INITIALIZATION METHOD OF VARIABLE RESISTANCE ELEMENT, AND NONVOLATILE STORAGE DEVICE - A method of driving a variable resistance element includes: a writing step performed by applying a writing voltage pulse having a first polarity to a variable resistance layer to change a resistance state of the layer from high to low; and an erasing step performed by applying an erasing voltage pulse having a second polarity to the layer to change the state from low to high. Here, |Vw1|>|Vw2| where Vw1 represents a voltage value of the writing voltage pulse for first to N-th writing steps (N≧10-28-2010
20110002154NONVOLATILE MEMORY ELEMENT, MANUFACTURING METHOD THEREOF, AND NONVOLATILE SEMICONDUCTOR DEVICE INCORPORATING NONVOLATILE MEMORY ELEMENT - A nonvolatile memory element of the present invention comprises a first electrode (01-06-2011
20110031465RESISTANCE VARIABLE ELEMENT AND MANUFACTURING METHOD THEREOF - A resistance variable element of the present invention comprises a first electrode (02-10-2011
20110044088VARIABLE RESISTANCE NONVOLATILE STORAGE DEVICE AND METHOD OF FORMING MEMORY CELL - A variable resistance nonvolatile storage device which includes (i) a semiconductor substrate (02-24-2011
20110080770METHOD OF PROGRAMMING VARIABLE RESISTANCE ELEMENT AND NONVOLATILE STORAGE DEVICE - Applying a writing voltage pulse having a first polarity to a metal oxide layer (04-07-2011
20110103131NONVOLATILE MEMORY ELEMENT AND NONVOLATILE MEMORY DEVICE - Provided is a nonvolatile memory element which has a small variation in operation and allow stable operation. The nonvolatile memory element includes: a first electrode (05-05-2011

Patent applications by Koji Katayama, Nara JP

Koji Katayama, Osaka-Shi JP

Patent application numberDescriptionPublished
20110058585GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE, AND METHOD OF FABRICATING GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE - A group-III nitride semiconductor laser device comprises a laser structure including a support base and a semiconductor region, and an electrode provided on the semiconductor region of the laser structure. The support base comprises a hexagonal group-III nitride semiconductor and has a semipolar primary surface, and the semiconductor region is provided on the semipolar primary surface of the support base. The semiconductor region includes a first cladding layer of a first conductivity type gallium nitride-based semiconductor, a second cladding layer of a second conductivity type gallium nitride-based semiconductor, and an active layer. The first cladding layer, the second cladding layer, and the active layer are arranged along a normal axis to the semipolar primary surface. The active layer comprises a gallium nitride-based semiconductor layer. The c-axis of the hexagonal group-III nitride semiconductor of the support base tilts at a finite angle ALPHA with respect to a normal axis toward an a-axis of the hexagonal group-III nitride semiconductor. The laser structure includes first and second fractured faces intersecting with an a-n plane defined by the normal axis and the a-axis of the hexagonal group-III nitride semiconductor. The laser cavity of the group-III nitride semiconductor laser device includes the first and second fractured faces. The laser structure includes first and second surfaces and the first surface is opposite to the second surface, and each of the first and second fractured faces extends from an edge of the first surface to an edge of the second surface.03-10-2011
20110075694III-Nitride semiconductor laser device, and method of fabricating the III-Nitride semiconductor laser device - In a III-nitride semiconductor laser device, a laser structure includes a support base with a semipolar primary surface comprised of a III-nitride semiconductor, and a semiconductor region provided on the semipolar primary surface of the support base. First and second dielectric multilayer films for an optical cavity of the nitride semiconductor laser device are provided on first and second end faces of the semiconductor region, respectively. The semiconductor region includes a first cladding layer of a first conductivity type gallium nitride-based semiconductor, a second cladding layer of a second conductivity type gallium nitride-based semiconductor, and an active layer provided between the first cladding layer and the second cladding layer. The first cladding layer, the second cladding layer, and the active layer are arranged in an axis normal to the semipolar primary surface. A c+ axis vector indicating a direction of the <0001> axis of the III-nitride semiconductor of the support base is inclined at an angle in the range of not less than 45 degrees and not more than 80 degrees or in the range of not less than 100 degrees and not more than 135 degrees toward a direction of any one crystal axis of the m- and a-axes of the III-nitride semiconductor with respect to a normal vector indicating a direction of the normal axis. The first and second end faces intersect with a reference plane defined by the normal axis and the one crystal axis of the hexagonal III-nitride semiconductor. The c+ axis vector makes an acute angle with a waveguide vector indicating a direction from the second end face to the first end face. A thickness of the second dielectric multilayer film is smaller than a thickness of the first dielectric multilayer film.03-31-2011
20110075695III-INTRIDE SEMICONDUCTOR LASER DEVICE, AND METHOD OF FABRICATING THE III-NITRIDE SEMICONDUCTOR LASER DEVICE - In a III-nitride semiconductor laser device, a laser structure includes a support base with a semipolar primary surface comprised of a III-nitride semiconductor, and a semiconductor region provided on the semipolar primary surface of the support base. First and second dielectric multilayer films for an optical cavity of the nitride semiconductor laser device are provided on first and second end faces of the semiconductor region, respectively. The semiconductor region includes a first cladding layer of a first conductivity type gallium nitride-based semiconductor, a second cladding layer of a second conductivity type gallium nitride-based semiconductor, and an active layer provided between the first cladding layer and the second cladding layer. The first cladding layer, the second cladding layer, and the active layer are arranged in an axis normal to the semipolar primary surface. A c+ axis vector indicating a direction of the <0001> axis of the III-nitride semiconductor of the support base is inclined at an angle in the range of not less than 45 degrees and not more than 80 degrees or in the range of not less than 100 degrees and not more than 135 degrees toward a direction of any one crystal axis of the m- and a-axes of the III-nitride semiconductor with respect to a normal vector indicating a direction of the normal axis. The first and second end faces intersect with a reference plane defined by the normal axis and the one crystal axis of the hexagonal III-nitride semiconductor. The c+ axis vector makes an acute angle with a waveguide vector indicating a direction from the second end face to the first end face. A thickness of the first dielectric multilayer film is smaller than a thickness of the second dielectric multilayer film.03-31-2011
20110158275GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE, AND METHOD OF FABRICATING GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE - In a III-nitride semiconductor laser device, a laser structure includes a support base comprised of a hexagonal III-nitride semiconductor and having a semipolar primary surface, and a semiconductor region provided on the semipolar primary surface of the support base. An electrode is provided on the semiconductor region of the laser structure.06-30-2011
20110158277GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE, METHOD OF FABRICATING GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE, AND EPITAXIAL SUBSTRATE - A III-nitride semiconductor laser device is provided with a laser structure and an electrode. The laser structure includes a support base which comprises a hexagonal III-nitride semiconductor and has a semipolar primary surface, and a semiconductor region provided on the semipolar primary surface. The electrode is provided on the semiconductor region. The semiconductor region includes a first cladding layer of a first conductivity type GaN-based semiconductor, a second cladding layer of a second conductivity type GaN-based semiconductor, and an active layer provided between the first cladding layer and the second cladding layer. The laser structure includes first and second fractured faces intersecting with an m-n plane defined by the m-axis of the hexagonal III-nitride semiconductor and an axis normal to the semipolar primary surface. A laser cavity of the III-nitride semiconductor laser device includes the first and second fractured faces. An angle ALPHA between the normal axis and the c-axis of the hexagonal III-nitride semiconductor is in the range of not less than 45 degrees and not more than 80 degrees or in the range of not less than 100 degrees and not more than 135 degrees. The laser structure includes a laser waveguide extending above the semipolar primary surface, and the laser waveguide extends in a direction of a waveguide vector directed from one to another of the first and second fractured faces. A c-axis vector indicating a direction of the c-axis of the hexagonal III-nitride semiconductor includes a projected component parallel to the semipolar primary surface and a vertical component parallel to the normal axis. An angle difference between the waveguide vector and the projected component is in the range of not less than −0.5 degrees and not more than +0.5 degrees.06-30-2011
20110164638GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE, METHOD OF FABRICATING GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE, AND METHOD OF ESTIMATING DAMAGE FROM FORMATION OF SCRIBE GROOVE - In a group-III nitride semiconductor laser device, a laser structure includes a support base comprising a hexagonal group-III nitride semiconductor and having a semipolar principal surface, and a semiconductor region provided on the semipolar principal surface of the support base. An electrode is provided on the semiconductor region of the laser structure. An angle between a normal axis to the semipolar principal surface and the c-axis of the hexagonal group-III nitride semiconductor is in a range of not less than 45° and not more than 80° or in a range of not less than 100° and not more than 135°. The laser structure includes a laser stripe extending in a direction of a waveguide axis above the semipolar principal surface of the support base. The laser structure includes first and second surfaces and the first surface is a surface opposite to the second surface. The laser structure includes first and second fractured faces intersecting with an m-n plane defined by the m-axis of the hexagonal group-III nitride semiconductor and the normal axis, a laser cavity of the group-III nitride semiconductor laser device includes the first and second fractured faces, and each of the first and second fractured faces extends from an edge of the first surface to an edge of the second surface. The waveguide axis extends from one to the other of the first and second fractured faces. The laser structure has first and second recesses provided each at a portion of the edge of the first surface in the first fractured face. The first and second recesses extend from the first surface of the laser structure, and bottom ends of the first and second recesses are located apart from the edge of the second surface of the laser structure. The first recess has an end at the first surface and the second recess has an end at the first surface. A first distance between the laser stripe and the end of the first recess is smaller than a second distance between the laser stripe and the end of the second recess.07-07-2011

Koji Katayama, Itami-Shi JP

Patent application numberDescriptionPublished
20080210959Light emitting apparatus - In order to provide light emitting devices which have simple constructions and thus can be fabricated easily, and can stably provide high light emission efficiencies for a long time period, a light emitting device includes an n-type nitride semiconductor layer at a first main surface side of a nitride semiconductor substrate, a p-type nitride semiconductor layer placed more distantly from the nitride semiconductor substrate than the n-type nitride semiconductor layer at the first main surface side and a light emitting layer placed between the n-type nitride semiconductor layer and the p-type nitride semiconductor layer at the first main surface side. The nitride semiconductor substrate has a resistivity of 0.5 Ω·cm or less and the p-type nitride semiconductor layer side is down-mounted so that light is emitted from the second main surface of the nitride semiconductor substrate at the opposite side from the first main surface.09-04-2008
20100120231METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE - A method for manufacturing a semiconductor device according to the present invention includes the following step: a step (S05-13-2010
20100216268MANUFACTURING METHOD OF A SEMICONDUCTOR ELEMENT - 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.08-26-2010
20100322276GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE, AND METHOD FOR FABRICATING GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE - Provided is a group-III nitride semiconductor laser device with a laser cavity allowing for a low threshold current, on a semipolar surface of a support base in which the c-axis of a hexagonal group-III nitride is tilted toward the m-axis. First and second fractured faces 12-23-2010
20110042706AlxGa(1-x)As Substrate, Epitaxial Wafer for Infrared LEDs, Infrared LED, Method of Manufacturing AlxGa(1-x)As Substrate, Method of Manufacturing Epitaxial Wafer for Infrared LEDs, and Method of Manufacturing Infrared LEDs02-24-2011
20110049542AlxGa(1-x)As Substrate, Epitaxial Wafer for Infrared LEDs, Infrared LED, Method of Manufacturing AlxGa(1-x)As Substrate, Method of Manufacturing Epitaxial Wafer for Infrared LEDs, and Method of Manufacturing Infrared LEDs - The present invention makes available Al03-03-2011
20110062466AlxGa(1-x)As Substrate, Epitaxial Wafer for Infrared LEDs, Infrared LED, Method of Manufacturing AlxGa(1-x)As Substrate, Method of Manufacturing Epitaxial Wafer for Infrared LEDs, and Method of Manufacturing Infrared LEDs03-17-2011
20110129997METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE - A method for manufacturing a semiconductor device according to the present invention includes the following step: a step (S06-02-2011
20110164637GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE, AND METHOD FOR FABRICATING GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE - Provided is a group-III nitride semiconductor laser device with a laser cavity allowing for a low threshold current, on a semipolar surface of a support base in which the c-axis of a hexagonal group-III nitride is tilted toward the m-axis. First and second fractured faces 07-07-2011

Patent applications by Koji Katayama, Itami-Shi JP

Koji Katayama, Osaka JP

Patent application numberDescriptionPublished
20100188884NONVOLATILE MEMORY ELEMENT, NONVOLATILE MEMORY APPARATUS, AND METHOD OF WRITING DATA TO NONVOLATILE MEMORY ELEMENT - A nonvolatile memory element comprises a first electrode (07-29-2010
20110108853COMPOUND SEMICONDUCTOR DEVICE - A compound semiconductor device having reduced contact resistance to an electrode is provided. The compound semiconductor device includes an n-substrate 05-12-2011
20110128983GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE, AND METHOD FOR FABRICATING GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE - Provided are a group-III nitride semiconductor laser device with a laser cavity to enable a low threshold current on a semipolar surface of a hexagonal group-III nitride, and a method for fabricating the group-III nitride semiconductor laser device on a stable basis. Notches, e.g., notch 06-02-2011
20110158276GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE, AND METHOD OF FABRICATING GROUP-III NITRIDE SEMICONDUCTOR LASER DEVICE - In a III-nitride semiconductor laser device, a laser structure includes a support base comprised of a hexagonal III-nitride semiconductor and having a semipolar primary surface, and a semiconductor region provided on the semipolar primary surface of the support base. An electrode is provided on the semiconductor region of the laser structure. The c-axis of the hexagonal III-nitride semiconductor of the support base is inclined at an angle ALPHA with respect to a normal axis toward the m-axis of the hexagonal III-nitride semiconductor. The angle ALPHA is in the range of not less than 45 degrees and not more than 80 degrees or in the range of not less than 100 degrees and not more than 135 degrees. The laser structure includes first and second fractured faces that intersect with an m-n plane defined by the m-axis of the hexagonal III-nitride semiconductor and the normal axis. A laser cavity of the III-nitride semiconductor laser device includes the first and second fractured faces. The laser structure includes first and second surfaces, and the first surface is opposite to the second surface. Each of the first and second fractured faces extends from an edge of the first surface to an edge of the second surface. The support base of the laser structure has a recess provided at a portion of the edge of the first surface in the first fractured face. The recess extends from a back surface of the support base, and an end of the recess is apart from the edge of the second surface of the laser structure.06-30-2011

Patent applications by Koji Katayama, Osaka JP

Koji Katayama, Okayama JP

Patent application numberDescriptionPublished
20100150308X-RAY INSPECTION APPARATUS - An X-ray inspection apparatus includes an X-ray radiating part, an X-ray detecting part, a mass estimation unit and a mass class determination unit. The X-ray radiating part is configured and arranged to radiate X-rays to an inspection target. The X-ray detecting part is configured and arranged to detect the X-rays radiated from the X-ray radiating part that transmitted through the inspection target. The mass estimation unit is configured to estimate a mass of the inspection target based on an amount of the X-rays detected by the X-ray detecting part. The mass class determination unit is configured to determine which mass class among a plurality of mass classes within a preset range the inspection target belongs to based on the mass of the inspection target estimated by the mass estimation unit.06-17-2010

Koji Katayama, Yamato-Shi JP

Patent application numberDescriptionPublished
20080223720MICROCHANNEL STRUCTURE AND FINE-PARTICLE PRODUCTION METHOD USING THE SAME - A microchannel structure including a dispersed-phase introduction channel which communicates with a dispersed-phase introduction inlet; a continuous-phase introduction channel which communicates with a continuous-phase introduction inlet; a discharge channel which communicates with a discharge outlet; a fine-particle formation channel; and a plurality of branch channels for dispersed-phase introduction which are microchannels; wherein one end of the fine-particle formation channel in a fluid traveling direction communicates with the continuous-phase introduction channel whereas the other end thereof communicates with the discharge channel; and wherein a side part of the dispersed-phase introduction channel and side part of the fine-particle formation channel communicate via the plurality of branch channel for dispersed-phase introduction.09-18-2008
20090028762MICROCHANNEL STRUCTURE BODY - A fine channel device, having an inlet opening for introducing a gas and an inlet path interconnecting with this inlet opening, a fine channel interconnecting with the inlet path, a discharge path interconnecting with the fine channel, and a discharge opening interconnecting with this discharge path. The inner diameter of the inlet path is greater than that of the fine channel, and either increases gradually, or remains identical, with increasing distance from the position where the inlet opening and the inlet path are in interconnection with each other.01-29-2009
20100019408MINUTE FLOW PATH STRUCTURE BODY AND DIE - A fine channel device containing a fine channel substrate that includes a fine channel for channeling fluids, and through holes, wherein the fine channel and the through holes are interconnected via an interconnection portion, as well as a mold that is equipped with pins forming the through holes in the fine channel substrate, wherein the positions of the pins and the number pins be altered as desired.01-28-2010
20100051543FINE CHANNEL DEVICE AND A CHEMICALLY OPERATING METHOD FOR FLUID USING THE DEVICE - A fine channel device including a fine channel provided with at least two inlet ports for feeding fluid, inlet channels communicated with the inlet ports, a confluent portion communicated with the inlet channels, a branch portion communicated with the fine channel, from which at least two outlet channels are branched to feed predetermined amounts of fluid, and outlet ports communicated with the outlet channels. The fine channel is provided with a plurality of partition walls arranged along a boundary formed by at least two kinds of fluid fed from the inlet ports so as not to cause mutual contamination of fluid. Furthermore, the plurality of partition walls are spaced apart at intervals in a flowing direction of fluid.03-04-2010

Patent applications by Koji Katayama, Yamato-Shi JP