Patents Assigned to Dowa Electronics Materials Co., Ltd.
  • Patent number: 10328534
    Abstract: A bonding material of a silver paste includes: fine silver particles having an average primary particle diameter of 1 to 50 nanometers, each of the fine silver particles being coated with an organic compound having a carbon number of not greater than 8, such as hexanoic acid; silver particles having an average primary particle diameter of 0.5 to 4 micrometers, each of the silver particles being coated with an organic compound, such as oleic acid; a solvent containing 3 to 7% by weight of an alcohol and 0.3 to 1% by weight of a triol; a dispersant containing 0.5 to 2% by weight of an acid dispersant and 0.01 to 0.1% by weight of phosphate ester dispersant; and 0.01 to 0.
    Type: Grant
    Filed: June 19, 2014
    Date of Patent: June 25, 2019
    Assignee: Dowa Electronics Materials Co., Ltd.
    Inventors: Keiichi Endoh, Minami Nagaoka, Satoru Kurita, Hiromasa Miyoshi, Yoshiko Kohno, Akihiro Miyazawa
  • Patent number: 10319807
    Abstract: A wafer group facilitates securing uniformity of products manufactured from the wafer group whose composition varies among wafers. A technique excludes uncertain factors in forming OF, forming OF with extremely high probability and extremely high accuracy, the wafer group being constituted by a plurality of wafers obtained from the same ingot, with all wafers having an orientation flat (OF), wherein the wafer group is constituted by 70 or more wafers, and in the OF orientation accuracy of the wafer group represented by an angle, the OF orientation accuracy in each wafer is within ±0.010°.
    Type: Grant
    Filed: December 9, 2015
    Date of Patent: June 11, 2019
    Assignee: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Shinya Shoji, Makoto Ishii, Kazuyuki Umetsu, Junji Sugiura
  • Patent number: 10290771
    Abstract: Provided is a III nitride semiconductor light emitting device with improved reliability capable of maintaining light output power reliably as compared with conventional devices, and a method of producing the same. The III-nitride semiconductor light-emitting device comprising: a light emitting layer, a p-type electron blocking layer, a p-type contact layer, and a p-side electrode in this order. The p-type contact layer has a first p-type contact layer co-doped with Mg and Si in contact with the p-type electron blocking layer and a second p-type contact layer doped with Mg in contact with the p-side electrode.
    Type: Grant
    Filed: April 17, 2017
    Date of Patent: May 14, 2019
    Assignee: DOWA Electronics Materials Co., Ltd.
    Inventor: Yasuhiro Watanabe
  • Patent number: 10283671
    Abstract: Provided is a method of producing a III nitride semiconductor light-emitting device having an n-type semiconductor layer, a light emitting layer, a barrier layer, and a p-type semiconductor layer. The p-type semiconductor layer is formed by forming an electron blocking layer on the light emitting layer; supplying a carrier gas containing nitrogen to a surface of the electron blocking layer; and forming a second p-type contact layer made of AlyGa1-yN on the electron blocking layer after the nitrogen carrier gas supply step. The second p-type contact formation step is performed using a carrier gas containing hydrogen. Source gases of Al and Ga are supplied to form a first p-type contact layer made of AlxGa1-xN with a thickness of more than 0 nm and 30 nm or less directly on the electron blocking layer and directly under the second p-type contact layer.
    Type: Grant
    Filed: November 13, 2018
    Date of Patent: May 7, 2019
    Assignee: DOWA Electronics Materials Co., Ltd.
    Inventors: Takehiko Fujita, Yasuhiro Watanabe
  • Patent number: 10272490
    Abstract: A silver powder, wherein the silver powder satisfies D50-IPA>D50-W, where in measurement of a volume-based particle size distribution of the silver powder by a laser diffraction particle size distribution analysis, D50-IPA (?m) is a cumulative 50% point of particle diameter of the silver powder when isopropyl alcohol (IPA) is used as a measurement solvent for dispersing the silver powder, and D50-W (?m) is a cumulative 50% point of particle diameter of the silver powder when water is used as a measurement solvent for dispersing the silver powder, and wherein a phosphorus content in the silver powder is 0.01% by mass or more but 0.3% by mass or less.
    Type: Grant
    Filed: September 25, 2015
    Date of Patent: April 30, 2019
    Assignee: DOWA Electronics Materials Co., Ltd.
    Inventors: Naoki Tahara, Noriaki Nogami, Hiroshi Kamiga
  • Publication number: 20190118257
    Abstract: There are provided a bonding material, which can prevent voids from being generated in a silver bonding layer by preventing the entrainment of bubbles during the formation of a coating film even if the coating film is thickened, and a bonding method using the same. The bonding material of a silver paste includes fine silver particles, a solvent and an addition agent, wherein the solvent contains a first solvent of a diol, such as octanediol, and a second solvent which is a polar solvent (preferably one or more selected from the group consisting of dibutyl diglycol, hexyl diglycol, decanol and dodecanol) having a lower surface tension than that of the first solvent and wherein the addition agent is a triol.
    Type: Application
    Filed: April 25, 2017
    Publication date: April 25, 2019
    Applicant: Dowa Electronics Materials Co., Ltd.
    Inventors: Satoru Kurita, Tatsuro Hori, Keiichi Endoh, Hiromasa Miyoshi
  • Patent number: 10252331
    Abstract: A silver powder, including: an organic substance on a surface of the silver powder, the organic substance containing at least one carboxyl group and at least one hydroxyl group in one molecule of the organic substance, wherein a ratio of (Casson yield value/BET specific surface area) is 500 or less, where the Casson yield value is a Casson yield value of a conductive paste and the BET specific surface area is a BET specific surface area of the silver powder, where the conductive paste has a composition in which the silver powder is 86% by mass, a glass fit is 1% by mass, ethyl cellulose is 0.6% by mass, texanol is 10.5% by mass, and zinc oxide is 1.9% by mass, and the conductive paste is prepared by kneading the composition with a planetary centrifugal stirrer and bubble remover and dispersing with a triple roll mill.
    Type: Grant
    Filed: July 27, 2015
    Date of Patent: April 9, 2019
    Assignee: DOWA Electronics Materials Co., Ltd.
    Inventors: Taro Nakanoya, Hiroshi Kamiga
  • Publication number: 20190100641
    Abstract: This disclosure relates to a fine silver particle dispersion comprising: (i) 60 to 95 wt. % of fine silver particles, wherein particle diameter (D50) of the fine silver particles is 50 to 300 nm, (ii) 4.5 to 39 wt. % of a solvent; and (iii) 0.1 to 3 wt. % of a resin, wherein the glass transition temperature (Tg) of the resin is 70 to 300° C., wherein the weight percentages are based on the weight of the fine silver particle dispersion.
    Type: Application
    Filed: October 4, 2017
    Publication date: April 4, 2019
    Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Shingo TERAGAWA, Takashi HINOTSU, Dave HUI, Michael Stephen WOLFE, Howard David GLICKSMAN, Haixin YANG
  • Publication number: 20190097216
    Abstract: There is provided a solution containing lithium and at least one of a niobium complex and a titanium complex, suppresses corrosiveness, excellent in storage stability, and suitable for forming a coating layer capable of improving battery characteristics of an active material, and a related technique, which is the solution containing lithium, at least one of a niobium complex and a titanium complex, and ammonia, wherein an amount of the ammonia in the solution is 1 mass % or less.
    Type: Application
    Filed: March 9, 2017
    Publication date: March 28, 2019
    Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Yoshiaki AIKI, Toshihiko UEYAMA, Koji TANOUE
  • Publication number: 20190081203
    Abstract: Provided is a method of producing a III nitride semiconductor light-emitting device having an n-type semiconductor layer, a light emitting layer, a barrier layer, and a p-type semiconductor layer. The p-type semiconductor layer is formed by forming an electron blocking layer on the light emitting layer; supplying a carrier gas containing nitrogen to a surface of the electron blocking layer; and forming a second p-type contact layer made of AlyGa1-yN on the electron blocking layer after the nitrogen carrier gas supply step. The second p-type contact formation step is performed using a carrier gas containing hydrogen. Source gases of Al and Ga are supplied to form a first p-type contact layer made of AlxGa1-xN with a thickness of more than 0 nm and 30 nm or less directly on the electron blocking layer and directly under the second p-type contact layer.
    Type: Application
    Filed: November 13, 2018
    Publication date: March 14, 2019
    Applicant: DOWA Electronics Materials Co., Ltd.
    Inventors: Takehiko FUJITA, Yasuhiro WATANABE
  • Publication number: 20190064688
    Abstract: A carrier core material formed with ferrite particles, the skewness Rsk of the particle is equal to or more than ?0.40 but equal to or less than ?0.20, and the kurtosis Rku of the particle is equal to or more than 3.20 but equal to or less than 3.50. Here, the maximum height Rz of the particle is equal to or more than 2.20 ?m but equal to or less than 3.50 ?m. Moreover, the ferrite particle contains at least either of Mn and Mg elements. In this way, cracking or chipping in a concave-convex portion of a particle surface is unlikely to occur, and moreover, the amount of coating resin used can be reduced without properties such as electrical resistance being lowered.
    Type: Application
    Filed: March 28, 2017
    Publication date: February 28, 2019
    Applicants: DOWA ELECTRONICS MATERIALS CO., LTD., DOWA IP CREATION CO., LTD.
    Inventors: Yuki KITAHARA, Shou OGAWA
  • Publication number: 20190035521
    Abstract: There is provided a magnetic substance containing substituted ?-iron oxide particles applicable as a magnetic toner of one-component development system, and a technique related thereto, which is the magnetic substance containing substituted ?-iron oxide particles in which a part of ?-iron oxide is substituted with a metal element other than iron, and satisfying at least one of the following conditions: (Condition 1) A molar extinction coefficient of a magnetic substance dispersion liquid at a wavelength of 450 nm is less than 770 dm3 mol?1 cm?1. (Condition 2) A molar extinction coefficient of the magnetic substance dispersion liquid at a wavelength of 500 nm is less than 430 dm3 mol?1 cm?1.
    Type: Application
    Filed: January 19, 2017
    Publication date: January 31, 2019
    Applicants: THE UNIVERSITY OF TOKYO, DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Shin-ichi OHKOSHI, Hiroko TOKORO, Kenji MASADA, Toshihiko UEYAMA
  • Patent number: 10193016
    Abstract: Provided is a III-nitride semiconductor light-emitting device having excellent device lifetime as compared with conventional devices and a method of producing the same. A III-nitride semiconductor light-emitting device 100 has an n-type semiconductor layer 30, a light emitting layer 40 containing at least Al, an electron blocking layer 50, and a p-type semiconductor layer 60 in this order. The light emitting layer 40 has a quantum well structure having well layers 41 and barrier layers 42. The electron blocking layer 50 is adjacent to the light emitting layer 40 and is formed from a layer having an Al content higher than that of the barrier layers 42 and the p-type semiconductor layer 60. The electron blocking layer 50 has a Si-based doped region layer 50a.
    Type: Grant
    Filed: February 3, 2016
    Date of Patent: January 29, 2019
    Assignee: DOWA Electronics Materials Co., Ltd.
    Inventors: Takehiko Fujita, Yasuhiro Watanabe
  • Publication number: 20190027620
    Abstract: There is provided a silver-coated copper powder which can improve the conversion efficiency of a solar cell in comparison with conventional silver-coated copper powders when it is used in an electrically conductive paste used for forming the busbar electrodes of the solar cell, the silver-coated copper powder being capable of producing a solar cell having a high conversion efficiency which is the same degree as that of a solar cell using silver powder, and a method for producing the same.
    Type: Application
    Filed: January 26, 2017
    Publication date: January 24, 2019
    Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Hiroshi Kamiga, Noriaki Nogami, Aiko Hirata
  • Patent number: 10185238
    Abstract: A carrier core material is provided that is formed with ferrite particles which can uniformly adhere a coupling agent to the entire surface. A carrier core material is formed with ferrite particles, and the powder pH of the ferrite particles is equal to or more than 9. Here, the ferrite particles are preferably formed of Mn ferrite or Mn—Mg ferrite. The ferrite particles preferably contain 45 wt % or more but 65 wt % or less of Fe, 15 wt % or more but 30 wt % or less of Mn and 5 wt % or less of Mg.
    Type: Grant
    Filed: July 21, 2017
    Date of Patent: January 22, 2019
    Assignees: DOWA ELECTRONICS MATERIALS CO., LTD., DOWA IP CREATION CO., LTD.
    Inventors: Yuto Kamai, Shinya Sasaki
  • Publication number: 20190009341
    Abstract: While a molten metal obtained by melting silver and a metal, which is selected from the group consisting of tin, zinc, lead and indium, in an atmosphere of nitrogen is allowed to drop, a high-pressure water (preferably pure water or alkaline water) is sprayed onto the molten metal in the atmosphere or an atmosphere of nitrogen to rapidly cool and solidify the molten metal to produce a silver alloy powder which comprises silver and the metal which is selected from the group consisting of tin, zinc, lead and indium and which has an average particle diameter of 0.5 to 20 ?m, the silver alloy powder having a temperature of not higher than 300° C. at a shrinking percentage of 0.5%, a temperature of not higher than 400° C. at a shrinking percentage of 1.0% and a temperature of not higher than 450° C. at a shrinking percentage of 1.5% in a thermomechanical analysis.
    Type: Application
    Filed: December 26, 2016
    Publication date: January 10, 2019
    Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Masahiro YOSHIDA, Yoshiyuki MICHIAKI, Kenichi INOUE
  • Publication number: 20190006558
    Abstract: A group III nitride semiconductor light-emitting element having longer element life than conventional group III nitride semiconductor light-emitting elements and a method of manufacturing the same are provided. A group III nitride semiconductor light-emitting element 100 comprises, in the following order: an n-type group III nitride semiconductor layer 30; a group III nitride semiconductor laminated body 40 obtained by alternately laminating a barrier layer 40a and a well layer 40b narrower in bandgap than the barrier layer 40a in the stated order so that the number of barrier layers 40a and the number of well layers 40b are both N, where N is an integer; an AlN guide layer 60; and a p-type group III nitride semiconductor layer 70, wherein the AlN guide layer 60 has a thickness of 0.5 nm or more and 2.0 nm or less.
    Type: Application
    Filed: June 22, 2016
    Publication date: January 3, 2019
    Applicant: DOWA Electronics Materials Co., Ltd.
    Inventors: Yasuhiro WATANABE, Takehiko FUJITA
  • Patent number: 10170213
    Abstract: There is provided a silver powder, which is able to obtain a conductive paste having a high thixotropic ratio and a high Casson yield value and which is able to form a conductive pattern having a low resistance, and a method for producing the same. An aliphatic amine such as hexadecylamine is added to a silver powder, the surface of which is coated with a fatty acid such as stearic acid, to be stirred and mixed to form the aliphatic amine on the outermost surface of the silver powder while allowing the fatty acid to react with the aliphatic amine to form an aliphatic amide such as hexadecanamide between the fatty acid and the aliphatic amine.
    Type: Grant
    Filed: January 2, 2018
    Date of Patent: January 1, 2019
    Assignee: Dowa Electronics Materials Co., Ltd.
    Inventors: Yoshiyuki Michiaki, Hiroshi Kamiga
  • Publication number: 20180366151
    Abstract: There is provided an oriented body containing platinum group-substituted-6 iron oxide particles typified by Rh-substituted ?-iron oxide or Ru-substituted ?-iron oxide applicable to MAMR, MIMR, or F-MIMR system, and a technique related thereto, containing platinum group element-substituted ?-iron oxide particles in which a part of ?-iron oxide is substituted with at least one element of platinum group elements, as magnetic particles wherein the degree of orientation of the magnetic particles defined by the degree of orientation=SQ (direction of magnetization easy-axes)/SQ (direction of magnetization hard-axes) exceeds 5.0, and a coercive force exceeds 31 kOe.
    Type: Application
    Filed: November 30, 2016
    Publication date: December 20, 2018
    Applicants: THE UNIVERSITY OF TOKYO, DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Shin-ichi OHKOSHI, Kenta IMOTO, Shizuka ANAN, Asuka NAMAI, Kenji MASADA
  • Patent number: 10147842
    Abstract: We propose a method of producing a III nitride semiconductor light-emitting device 1 having a p-type semiconductor layer 150 in this order, wherein the p-type semiconductor layer 150 is formed by the steps comprising: an electron blocking layer formation step for forming an electron blocking layer 51 having an Al content higher than that of the barrier layer 42, on the light emitting layer 40; a nitrogen carrier gas supply step for supplying at least a carrier gas containing nitrogen as a main component to a surface of the electron blocking layer 51; and a second p-type contact formation step for forming a second p-type contact layer 55 made of AlyGa1-yN on the electron blocking layer 51 after the nitrogen carrier gas supply step, and wherein the second p-type contact formation step is performed using a carrier gas containing hydrogen as a main component.
    Type: Grant
    Filed: December 8, 2015
    Date of Patent: December 4, 2018
    Assignee: DOWA Electronics Materials Co., Ltd.
    Inventors: Takehiko Fujita, Yasuhiro Watanabe