Abstract: A periodic table Group 13 metal nitride crystals grown with a non-polar or semi-polar principal surface have numerous stacking faults. The purpose of the present invention is to provide a period table Group 13 metal nitride crystal wherein the occurrence of stacking faults of this kind are suppressed. The present invention achieves the foregoing by a periodic table Group 13 metal nitride crystal being characterized in that, in a Qx direction intensity profile that includes a maximum intensity and is derived from an isointensity contour plot obtained by x-ray reciprocal lattice mapping of (100) plane of the periodic table Group 13 metal nitride crystal, a Qx width at 1/300th of peak intensity is 6×10?4 rlu or less.

Abstract: A periodic table Group 13 metal nitride crystals grown with a non-polar or semi-polar principal surface have numerous stacking faults. The purpose of the present invention is to provide a period table Group 13 metal nitride crystal wherein the occurrence of stacking faults of this kind are suppressed. The present invention achieves the foregoing by a periodic table Group 13 metal nitride crystal being characterized in that, in a Qx direction intensity profile that includes a maximum intensity and is derived from an isointensity contour plot obtained by x-ray reciprocal lattice mapping of (100) plane of the periodic table Group 13 metal nitride crystal, a Qx width at 1/300th of peak intensity is 6×10?4 rlu or less.

Abstract: The main purpose of the present invention is to provide: a nonpolar or semipolar GaN substrate, in which a nitride semiconductor crystal having a low stacking fault density can be epitaxially grown on the main surface of the substrate, and a technique required for the production of the substrate. This invention provides: a method for manufacturing an M-plane GaN substrate comprising; forming a mask pattern having a line-shaped opening parallel to an a-axis of a C-plane GaN substrate on an N-polar plane of the C-plane GaN substrate, growing a plane-shape GaN crystal of which thickness direction is an m-axis direction from the opening of the mask pattern by an ammonotharmal method, and cutting out the M-plane GaN substrate from the plane-shape GaN crystal.

Abstract: The invention provides a nonpolar or semipolar GaN substrate, in which a nitride semiconductor crystal having a low stacking fault density can be epitaxially grown on the main surface of the substrate, and a method for manufacturing an M-plane GaN substrate by forming a mask pattern having a line-shaped opening parallel to an a-axis of a C-plane GaN substrate on an N-polar plane of the C-plane GaN substrate, growing a plane-shape GaN crystal of which thickness direction is an m-axis direction from the opening of the mask pattern by an ammonothermal method, and cutting out the M-plane GaN substrate from the plane-shape GaN crystal.

Abstract: An object is to provide a nonpolar or semipolar GaN substrate having improved size and crystal quality. A self-standing GaN substrate has an angle between the normal of the principal surface and an m-axis of 0 degrees or more and 20 degrees or less, wherein: the size of the projected image in a c-axis direction when the principal surface is vertically projected on an M-plane is 10 mm or more; and when an a-axis length is measured on an intersection line between the principal surface and an A-plane, a low distortion section with a section length of 6 mm or more and with an a-axis length variation within the section of 10.0×10?5 ? or less is observed.

Abstract: The main purpose of the present invention is to provide: a nonpolar or semipolar GaN substrate, in which a nitride semiconductor crystal having a low stacking fault density can be epitaxially grown on the main surface of the substrate, and a technique required for the production of the substrate. This invention provides: a method for manufacturing an M-plane GaN substrate comprising; forming a mask pattern having a line-shaped opening parallel to an a-axis of a C-plane GaN substrate on an N-polar plane of the C-plane GaN substrate, growing a plane-shape GaN crystal of which thickness direction is an m-axis direction from the opening of the mask pattern by an ammonotharmal method, and cutting out the M-plane GaN substrate from the plane-shape GaN crystal.

Abstract: A periodic table Group 13 metal nitride crystals grown with a non-polar or semi-polar principal surface have numerous stacking faults. The purpose of the present invention is to provide a period table Group 13 metal nitride crystal wherein the occurrence of stacking faults of this kind are suppressed. The present invention achieves the foregoing by a periodic table Group 13 metal nitride crystal being characterized in that, in a Qx direction intensity profile that includes a maximum intensity and is derived from an isointensity contour plot obtained by x-ray reciprocal lattice mapping of (100) plane of the periodic table Group 13 metal nitride crystal, a Qx width at 1/300th of peak intensity is 6×10?4 rlu or less.

Abstract: The problems addressed by the present invention lies in providing a Group III nitride semiconductor substrate having a principal plane on which high-quality crystals can be grown and also providing a method for producing a Group III nitride semiconductor substrate capable of obtaining a crystal which has few stacking faults and in which stacking faults in directions parallel to the polar plane in particular have been greatly suppressed. The problem is solved by means of a Group III nitride semiconductor substrate having a plane other than a C plane as a principal plane, wherein a ratio (W1/W2) of a tilt angle distribution W1 of the principal plane in the direction of a line of intersection between the principal plane and the C plane to a tilt angle distribution W2 of the principal plane in a direction orthogonal to the line of intersection is less than 1.

Abstract: A method for efficiently producing a plate-like nitride semiconductor crystal having the desired principal plane in a simple method is provided. A raw material gas is fed to a seed crystal in which a ratio (L/W) of length L in a longitudinal direction and maximum width W, of a plane of projection obtained by projecting a crystal growth face on the seed crystal in a growth direction is from 2 to 400, and the maximum width W is 5 mm or less, thereby growing a plate-like semiconductor crystal on the seed crystal.

Abstract: A production process for a nitride semiconductor crystal, comprising growing a semiconductor layer on a seed substrate to obtain a nitride semiconductor crystal, wherein the seed substrate comprises a plurality of seed substrates made of the same material, at least one of the plurality of seed substrates differs in the off-angle from the other seed substrates, and a single semiconductor layer is grown by disposing the plurality of seed substrates in a semiconductor crystal production apparatus, such that when the single semiconductor layer is grown on the plurality of seed substrates, the off-angle distribution in the single semiconductor layer becomes smaller than the off-angle distribution in the plurality of seed substrates.

Abstract: A Group-III nitride semiconductor substrate having a flat surface with a dangling bond density of higher than 14.0 nm?2 is produced by cleaning the surface having a dangling bond density of higher than 14.0 nm?2 with a cleaning agent containing an ammonium salt.

Abstract: A Group-III nitride semiconductor substrate having a flat surface with a dangling bond density of higher than 14.0 nm?2 is produced by cleaning the surface having a dangling bond density of higher than 14.0 nm?2 with a cleaning agent containing an ammonium salt.

Abstract: A method for efficiently producing a plate-like nitride semiconductor crystal having the desired principal plane in a simple method is provided. A raw material gas is fed to a seed crystal in which a ratio (L/W) of length L in a longitudinal direction and maximum width W, of a plane of projection obtained by projecting a crystal growth face on the seed crystal in a growth direction is from 2 to 400, and the maximum width W is 5 mm or less, thereby growing a plate-like semiconductor crystal on the seed crystal.

Abstract: A soot generation amount estimation apparatus obtains a generation speed of a precursor of soot (accordingly, the concentration of the precursor) in consideration of formation of the precursor from fuel, thermal decomposition of the formed precursor, and formation of soot from the formed precursor, and estimates a generation speed of soot (accordingly, the concentration of soot (the generation amount of soot)) in consideration of formation of soot from the precursor, which depends on the concentration of the precursor, and oxidation of the formed soot. The apparatus employs a reaction model in which the reaction process in which soot is generated from fuel is divided into two steps; i.e., a reaction process in which a precursor is generated from fuel and a reaction process in which soot is generated from the precursor. Thus, phenomena, such as a “delay in soot generation” in the reaction process in which soot is generated from fuel, can be accurately simulated.

Abstract: A Group-III nitride semiconductor substrate having a flat surface with a dangling bond density of higher than 14.0 nm?2 is produced by cleaning the surface having a dangling bond density of higher than 14.0 nm?2 with a cleaning agent containing an ammonium salt.

Abstract: A Group-III nitride semiconductor substrate having a flat surface with a dangling bond density of higher than 14.0 nm?2 is produced by cleaning the surface having a dangling bond density of higher than 14.0 nm?2 with a cleaning agent containing an ammonium salt.

Abstract: A soot generation amount estimation apparatus obtains a generation speed of a precursor of soot (accordingly, the concentration of the precursor) in consideration of formation of the precursor from fuel, thermal decomposition of the formed precursor, and formation of soot from the formed precursor, and estimates a generation speed of soot (accordingly, the concentration of soot (the generation amount of soot)) in consideration of formation of soot from the precursor, which depends on the concentration of the precursor, and oxidation of the formed soot. The apparatus employs a reaction model in which the reaction process in which soot is generated from fuel is divided into two steps; i.e., a reaction process in which a precursor is generated from fuel and a reaction process in which soot is generated from the precursor. Thus, phenomena, such as a “delay in soot generation” in the reaction process in which soot is generated from fuel, can be accurately simulated.

Abstract: An exhaust gas filter including a filter base body which has many pores and has a flow-in surface, in which exhaust gas containing particulate matter flows, and an exhaust surface, from which purified gas is exhausted, the exhaust gas filter having at least a function of removing the particulate matter from the exhaust gas by passing the exhaust gas through the filter base body from the flow-in surface toward the exhaust surface, wherein a micropore structure, in which agglomerates of particulates having fine gaps are connectedly provided and which is air-permeable and which collects the particulate matter contained in the exhaust gas, is provided at the filter base body at a surface and/or within the pores which open and communicate the flow-in surface and the exhaust surface to and with one another.

Abstract: An NOx storage-and-reduction type catalyst is used which exhibits a saturated NOx storage amount of 5 g or more as NO2 with respect to 1 liter of a catalyst volume at 500° C., and rich spiking is controlled so that an actual NOx storage amount of the NOx storage-and-reduction type catalyst becomes 50% or less of the saturated NOx storage amount. Since the saturated NOx storage amount is large, the NOx storage amount is large even when it is 50% or less, it is possible to prolong intervals of the rich spiking. Then, since NOx storage component stores NOx preferentially into the sites which are likely to store and release NOx, a reduction efficiency is high. Therefore, while prolonging the intervals of the rich spiking and sustaining an effect of mileage improvement, it is possible to improve the reduction efficiency of NOx.

Abstract: In a fuel cell system 10, a cracking unit 20 is provided upstream of a reformer 36. When the cracking unit 20 is supplied with oxygen and gasoline as a hydrocarbon-based fuel, the gasoline is partially oxidized and decomposed using oxidation-generated heat to give a hydrocarbon with a lower carbon number. The hydrocarbon with the lower carbon number obtained by such gasoline pyrolysis is fed to the reformer 36 and supplied to a reforming reaction zone.