Patent application number | Description | Published |
20080277667 | Method of producing III-nitride substrate | 11-13-2008 |
20080296585 | GROWTH METHOD OF GaN CRYSTAL, AND GaN CRYSTAL SUBSTRATE - A method of producing a GaN crystal is directed to growing a GaN crystal on a GaN seed crystal substrate. The method includes the steps of preparing a GaN seed crystal substrate including a first dopant such that the thermal expansion coefficient of the GaN seed crystal substrate becomes greater than that of the GaN crystal, and growing the GaN crystal to a thickness of at least 1 mm on the GaN seed crystal substrate. Accordingly, there can be provided a method of producing a GaN crystal that can suppress generation of a crack and grow a thick GaN crystal, and a GaN crystal substrate. | 12-04-2008 |
20090029550 | Method of Manufacturing Nitride Substrate for Semiconductors - In an independent GaN film manufactured by creating a GaN layer on a base heterosubstrate using vapor-phase deposition and then removing the base substrate, owing to layer-base discrepancy in thermal expansion coefficient and lattice constant, bow will be a large ±40 μm to ±100 μm. Since with that bow device fabrication by photolithography is challenging, reducing the bow to +30 μm to −20 μm is the goal. The surface deflected concavely is ground to impart to it a damaged layer that has a stretching effect, making the surface become convex. The damaged layer on the surface having become convex is removed by etching, which curtails the bow. Alternatively, the convex surface on the side opposite the surface having become convex is ground to generate a damaged layer. With the concave surface having become convex due to the damaged layer, suitably etching off the damaged layer curtails the bow. | 01-29-2009 |
20090045410 | GaN SUBSTRATE AND SEMICONDUCTOR DEVICE PREPARED BY USING METHOD AND APPARATUS OF POLISHING GaN SUBSTRATE - In a polishing method of a GaN substrate according to this invention, first, while supplying a polishing solution | 02-19-2009 |
20090263955 | GaN single crystal substrate and method of making the same - The method of making a GaN single crystal substrate comprises a mask layer forming step of forming on a GaAs substrate | 10-22-2009 |
20090273060 | GROUP III NITRIDE CRYSTAL AND METHOD FOR SURFACE TREATMENT THEREOF, GROUP III NITRIDE STACK AND MANUFACTURING METHOD THEREOF, AND GROUP III NITRIDE SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF - A method for surface treatment of a group III nitride crystal includes the steps of lapping a surface of a group III nitride crystal using a hard abrasive grain with a Mohs hardness higher than 7, and abrasive-grain-free polishing the lapped surface of the group III nitride crystal using a polishing solution without containing abrasive grain, and the polishing solution without containing abrasive grain has a pH of not less than 1 and not more than 6, or not less than 8.5 and not more than 14. Accordingly, the method for surface treatment of a group III nitride crystal can be provided according to which hard abrasive grains remaining at the lapped crystal can be removed to reduce impurities at the crystal surface. | 11-05-2009 |
20100009526 | FABRICATION METHOD AND FABRICATION APPARATUS OF GROUP III NITRIDE CRYSTAL SUBSTANCE - A fabrication method of a group III nitride crystal substance includes the steps of cleaning the interior of a reaction chamber by introducing HCl gas into the reaction chamber, and vapor deposition of a group III nitride crystal substance in the cleaned reaction chamber. A fabrication apparatus of a group III nitride crystal substance includes a configuration to introduce HCl gas into the reaction chamber, and a configuration to grow a group III nitride crystal substance by HVPE. Thus, a fabrication method of a group III nitride crystal substance including the method of effectively cleaning deposits adhering inside the reaction chamber during crystal growth, and a fabrication apparatus employed in the fabrication method are provided. | 01-14-2010 |
20110065265 | FABRICATION METHOD AND FABRICATION APPARATUS OF GROUP III NITRIDE CRYSTAL SUBSTANCE - A fabrication method of a group III nitride crystal substance includes the steps of cleaning the interior of a reaction chamber by introducing HCl gas into the reaction chamber, and vapor deposition of a group III nitride crystal substance in the cleaned reaction chamber. A fabrication apparatus of a group III nitride crystal substance includes a configuration to introduce HCl gas into the reaction chamber, and a configuration to grow a group III nitride crystal substance by HVPE. Thus, a fabrication method of a group III nitride crystal substance including the method of effectively cleaning deposits adhering inside the reaction chamber during crystal growth, and a fabrication apparatus employed in the fabrication method are provided. | 03-17-2011 |
20110068434 | NITRIDE SEMICONDUCTOR SUBSTRATE, SEMICONDUCTOR DEVICE, AND METHODS FOR MANUFACTURING NITRIDE SEMICONDUCTOR SUBSTRATE AND SEMICONDUCTOR DEVICE - A nitride semiconductor substrate having a main surface serving as a semipolar plane and provided with a chamfered portion capable of effectively preventing cracking and chipping, a semiconductor device fabricated using the nitride semiconductor substrate, and a method for manufacturing the nitride semiconductor substrate and the semiconductor device are provided. The nitride semiconductor substrate includes a main surface inclined at an angle of 71° or more and 79° or less with respect to the (0001) plane toward the [1-100] direction or inclined at an angle of 71° or more and 79° or less with respect to the (000-1) plane toward the [−1100] direction; and a chamfered portion located at an edge of an outer periphery of the main surface. The chamfered portion is inclined at an angle θ | 03-24-2011 |
20110121311 | METHOD FOR MANUFACTURING SEMICONDUCTOR SUBSTRATE, METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE, SEMICONDUCTOR SUBSTRATE, AND SEMICONDUCTOR DEVICE - The present invention provides a method for manufacturing a semiconductor substrate including a low-resistance nitride layer laminated on a substrate, a method for manufacturing a semiconductor device, a semiconductor substrate, and a semiconductor device. A method for manufacturing a semiconductor substrate of the present invention includes the following steps: A nitride substrate having a principal surface and a back surface opposite to the principal surface is prepared. Vapor-phase ions are implanted into the back surface of the nitride substrate. The back surface of the nitride substrate is bonded to a dissimilar substrate to form a bonded substrate. The nitride substrate is partially separated from the bonded substrate to form a laminated substrate including the dissimilar substrate and a nitride layer. The laminated substrate is heat-treated at a temperature over 700° C. | 05-26-2011 |
20110146565 | GROUP III NITRIDE CRYSTAL AND METHOD FOR SURFACE TREATMENT THEREOF, GROUP III NITRIDE STACK AND MANUFACTURING METHOD THEREOF, AND GROUP III NITRIDE SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF - A method for surface treatment of a group III nitride crystal includes the steps of lapping a surface of a group III nitride crystal using a hard abrasive grain with a Mohs hardness higher than 7, and abrasive-grain-free polishing the lapped surface of the group III nitride crystal using a polishing solution without containing abrasive grain, and the polishing solution without containing abrasive grain has a pH of not less than 1 and not more than 6, or not less than 8.5 and not more than 14. Accordingly, the method for surface treatment of a group III nitride crystal can be provided according to which hard abrasive grains remaining at the lapped crystal can be removed to reduce impurities at the crystal surface. | 06-23-2011 |
20110163323 | GaN SINGLE CRYSTAL SUBSTRATE AND METHOD OF MAKING THE SAME - The method of making a GaN single crystal substrate comprises a mask layer forming step of forming on a GaAs substrate | 07-07-2011 |
20120135549 | Method of Processing Gallium-Nitride Semiconductor Substrates - Polishing a nitride semiconductor monocrystalline wafer leaves it with a process-transformed layer. The process-transformed layer has to be etched to be removed. The chemical inertness of nitride semiconductor materials has, however, precluded suitable etching. Although potassium hydroxide, for example, or sulfuric acid have been proposed as GaN etchants, their ability to corrosively remove material from the Ga face is weak. Dry etching utilizing a halogen plasma is carried out in order to remove the process-transformed layer. The Ga face can be etched off with the halogen plasma. Nevertheless, owing to the dry etching, a problem arises again—surface contamination due to metal particles. To address the problem, wet etching with, as the etchant, solutions such as HF+H | 05-31-2012 |
20120319129 | SUBSTRATE, EPITAXIAL LAYER PROVIDED SUBSTRATE, METHOD FOR PRODUCING SUBSTRATE, AND METHOD FOR PRODUCING EPITAXIAL LAYER PROVIDED SUBSTRATE - The present invention provides a substrate formed at a low cost and having a controlled plate shape, an epitaxial layer provided substrate obtained by forming an epitaxial layer on the substrate, and methods for producing them. The method for producing the substrate according to the present invention includes an ingot growing step (S | 12-20-2012 |
20130032013 | METHOD OF MANUFACTURING GROUP III NITRIDE CRYSTAL SUBSTRATE - A method of manufacturing a group III nitride crystal substrate includes the step of preparing a group III nitride crystal body and the step of producing a group III nitride crystal substrate by slicing the group III nitride crystal body with a resin-fixed-abrasive wire. Accordingly, the method of manufacturing a group III nitride crystal substrate is provided that enables large-sized group III nitride crystal substrates with a small warp and a small arithmetic mean surface roughness to be manufactured by means of a resin-fixed-abrasive wire efficiently with a high yield. | 02-07-2013 |
20130061841 | SAW WIRE AND METHOD OF MANUFACTURING GROUP III NITRIDE CRYSTAL SUBSTRATE USING THE SAME - A method of manufacturing a group III nitride crystal substrate slices a group III nitride crystal body with a saw wire which includes a steel wire having a carbon concentration of 0.90-0.95 mass %, a silicon concentration of 0.12-0.32 mass %, a manganese concentration of 0.40-0.90 mass %, a phosphorus concentration of 0.025 mass % or less, a sulfur concentration of 0.025 mass % or less, and a copper concentration of 0.20 mass % or less, and has a diameter of not less than 0.07 mm and less than 0.16 mm, a tensile strength at break of higher than 4200 N/mm | 03-14-2013 |
20130134434 | NITRIDE SEMICONDUCTOR SUBSTRATE - A nitride semiconductor device includes a main surface and an indicator portion. The main surface is a plane inclined by at least 71° and at most 79° in a [1-100] direction from a (0001) plane or a plane inclined by at least 71° and at most 79° in a [−1100] direction from a (000-1) plane. The indicator portion indicates a (−1017) plane, a (10-1-7) plane, or a plane inclined by at least −4° and at most 4° in the [1-100] direction from these planes and inclined by at least −0.5° and at most 0.5° in a direction orthogonal to the [1-100] direction. | 05-30-2013 |
20130244406 | FABRICATION METHOD AND FABRICATION APPARATUS OF GROUP III NITRIDE CRYSTAL SUBSTANCE - A fabrication method of a group III nitride crystal substance includes the steps of cleaning the interior of a reaction chamber by introducing HCl gas into the reaction chamber, and vapor deposition of a group III nitride crystal substance in the cleaned reaction chamber. A fabrication apparatus of a group III nitride crystal substance includes a configuration to introduce HCl gas into the reaction chamber, and a configuration to grow a group III nitride crystal substance by HVPE. Thus, a fabrication method of a group III nitride crystal substance including the method of effectively cleaning deposits adhering inside the reaction chamber during crystal growth, and a fabrication apparatus employed in the fabrication method are provided. | 09-19-2013 |
20130252401 | NITRIDE SEMICONDUCTOR SUBSTRATE, SEMICONDUCTOR DEVICE, AND METHODS FOR MANUFACTURING NITRIDE SEMICONDUCTOR SUBSTRATE AND SEMICONDUCTOR DEVICE - A nitride semiconductor substrate having a main surface serving as a semipolar plane and provided with a chamfered portion capable of effectively preventing cracking and chipping, a semiconductor device fabricated using the nitride semiconductor substrate, and a method for manufacturing the nitride semiconductor substrate and the semiconductor device are provided. The nitride semiconductor substrate includes a main surface inclined at an angle of 71° or more and 79° or less with respect to the (0001) plane toward the [1-100] direction or inclined at an angle of 71° or more and 79° or less with respect to the (000-1) plane toward the [−1100] direction; and a chamfered portion located at an edge of an outer periphery of the main surface. The chamfered portion is inclined at an angle θ | 09-26-2013 |
20140103353 | GROUP III NITRIDE COMPOSITE SUBSTRATE AND METHOD FOR MANUFACTURING THE SAME, LAMINATED GROUP III NITRIDE COMPOSITE SUBSTRATE, AND GROUP III NITRIDE SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING THE SAME - A group III nitride composite substrate includes a support substrate and a group III nitride film. A ratio s | 04-17-2014 |