Patents Assigned to Dowa Electronics Materials Co., Ltd.
  • Publication number: 20210162495
    Abstract: There is provided a spherical silver powder which is capable of being sintered at a lower temperature. The spherical silver powder of spherical silver particles has cavities, each of which is formed in a corresponding one of the spherical silver particles and each of which has a major axis of 100 to 1000 nm and a minor axis of 10 nm or more, the ratio of the major axis to the minor axis (major axis/minor axis) being 5 or more, the major axis being the length of the long side of a rectangle which has a minimum area and which circumscribes the outline of a cross-section of a corresponding one of the cavities on an image of the cross-section of the corresponding one of the silver particles exposed by polishing the surface of a resin after the silver powder is embedded in the resin, and the minor axis being the length of the narrow side of the rectangle.
    Type: Application
    Filed: December 13, 2018
    Publication date: June 3, 2021
    Applicant: Dowa Electronics Materials Co., Ltd.
    Inventors: Masaya Osako, Taro Nakanoya
  • Publication number: 20210167249
    Abstract: A semiconductor light-emitting element capable of reducing multipeaks to thereby achieve a single peak in an emission spectrum is provided. A semiconductor light-emitting element according to the present disclosure includes, in this order, a substrate, a reflective layer, a first conductivity type cladding layer made of InGaAsP containing at least In and P, a semiconductor light-emitting layer having an emission central wavelength of 1000 nm to 2200 nm, and a second conductivity type cladding layer made of InGaAsP containing at least In and P, wherein the second conductivity type cladding layer is configured to be on a light extraction side. The surface of a light extraction face of the second conductivity type cladding layer is a roughened surface which has a surface roughness Ra of 0.03 ?m or more and has a random irregularity pattern.
    Type: Application
    Filed: April 18, 2019
    Publication date: June 3, 2021
    Applicant: DOWA Electronics Materials Co., Ltd.
    Inventors: Jumpei YAMAMOTO, Tetsuya IKUTA
  • Publication number: 20210167250
    Abstract: A deep ultraviolet light-emitting element of this disclosure includes, in this order, an n-type semiconductor layer; a light-emitting layer; and a p-type semiconductor layer. An emission spectrum of the deep ultraviolet light-emitting element has a primary emission peak wavelength in a wavelength range of 200 nm or more and 350 nm or less, and a blue-violet secondary light emission component having a relative emission intensity of 0.03% to 10% across a wavelength range of 430 to 450 nm, a yellow-green secondary light emission component having a relative emission intensity of 0.03 to 10% across a wavelength range of 540 to 580 nm, when the relative emission intensities are expressed relative to an emission intensity at the primary emission peak wavelength taken as 100%. The ratio of an emission intensity at a wavelength of 435 nm to an emission intensity at a wavelength of 560 nm is 0.5 to 2.
    Type: Application
    Filed: April 18, 2019
    Publication date: June 3, 2021
    Applicant: DOWA Electronics Materials Co., Ltd.
    Inventors: Tomohiko SHIBATA, Takehiro MIYAJI
  • Patent number: 11024769
    Abstract: A group III nitride semiconductor light-emitting element comprises, in the following order: an n-type group III nitride semiconductor layer; a group III nitride semiconductor laminated body obtained by alternately laminating a barrier layer and a well layer narrower in bandgap than the barrier layer in the stated order so that the number of barrier layers and the number of well layers are both N, where N is an integer; an AlN guide layer; and a p-type group III nitride semiconductor layer. The AlN guide layer has a thickness of 0.7 nm or more and 1.7 nm or less. An Nth well layer in the group III nitride semiconductor laminated body and the AlN guide layer are in contact with each other, or a final barrier layer is further provided between the Nth well layer and the AlN guide layer.
    Type: Grant
    Filed: September 12, 2019
    Date of Patent: June 1, 2021
    Assignee: DOWA Electronics Materials Co., Ltd.
    Inventors: Yasuhiro Watanabe, Takehiko Fujita
  • Patent number: 11009629
    Abstract: Provided is an anti-reflection film having low reflectance even for oblique incidence, which film is highly moisture resistant and is suitable for use in a deep ultraviolet light-emitting device. The anti-reflection film includes: a first layer having a first refractive index, provided on the window member; a second layer having a second refractive index; and a third layer having a third refractive index. For light having a wavelength of 280 nm, the first refractive index is 1.6 or more and 2.0 or less, the second refractive index is 2.0 or more and 2.7 or less and is higher than the first refractive index, the third refractive index is 1.3 or more and 1.6 or less and is lower than the first refractive index, and materials of the layers having the first refractive index, the second refractive index, and the third refractive index are made of oxides different from each other.
    Type: Grant
    Filed: December 22, 2017
    Date of Patent: May 18, 2021
    Assignee: DOWA Electronics Materials Co., Ltd.
    Inventor: Tsukasa Maruyama
  • Publication number: 20210132520
    Abstract: According to the present invention, there is provided a carrier core material that is formed of ferrite particles in which 48 to 52 mass % of Fe, 16 to 22 mass % of Mn, 1.0 to 3.5 mass % of Mg and 0.05 to 0.5 mass % of Ca are included, and when an electrical resistance value with an applied voltage of 500 V in an environment (in an L/L environment) in which the temperature is 10° C. and the relative humidity is 35% is RL (?·cm), and an electrical resistance value with an applied voltage of 500 V in an environment (in an H/H environment) in which the temperature is 30° C. and the relative humidity is 70% is RH (?·cm), formula (1) below is satisfied. 0.1?(log RL?log RH)?0.
    Type: Application
    Filed: March 15, 2018
    Publication date: May 6, 2021
    Applicants: DOWA ELECTRONICS MATERIALS CO., LTD., DOWA IP CREATION CO., LTD.
    Inventors: Takeshi KAWAUCHI, Yohei ISHIKAWA, Hiroyuki MIYANO
  • Patent number: 10991850
    Abstract: A group III nitride semiconductor light-emitting element comprises, in the following order: an n-type group III nitride semiconductor layer; a group III nitride semiconductor laminated body obtained by alternately laminating a barrier layer and a well layer narrower in bandgap than the barrier layer in the stated order so that the number of barrier layers and the number of well layers are both N, where N is an integer; an AlN guide layer; and a p-type group III nitride semiconductor layer. The AlN guide layer has a thickness of 0.7 nm or more and 1.7 nm or less. An Nth well layer in the group III nitride semiconductor laminated body and the AlN guide layer are in contact with each other, or a final barrier layer is further provided between the Nth well layer and the AlN guide layer.
    Type: Grant
    Filed: September 12, 2019
    Date of Patent: April 27, 2021
    Assignee: DOWA Electronics Materials Co., Ltd.
    Inventors: Yasuhiro Watanabe, Takehiko Fujita
  • Publication number: 20210078081
    Abstract: There is provided a silver powder which has a small average particle diameter and a small thermal shrinkage percentage, and a method for producing the same. While a molten metal of silver heated to a temperature (1292 to 1692° C.), which is higher than the melting point (962° C.) of silver by 330 to 730° C., is allowed to drop, a high-pressure water is sprayed onto the molten metal of silver (preferably at a water pressure of 90 to 160 MPa) to rapidly cool and solidify the molten metal of silver to powderize silver to produce a silver powder which has an average particle diameter of 1 to 6 ?m and a shrinkage percentage of not greater than 8% (preferably not greater than 7%) at 500° C., the product of the average particle diameter by the shrinkage percentage at 500° C. being 1 to 11 ?m·% (preferably 1.5 to 10.5 ?m·%).
    Type: Application
    Filed: November 2, 2020
    Publication date: March 18, 2021
    Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Atsushi Ebara, Kenichi Inoue, Yoshiyuki Michiaki, Takahiro Yamada, Masahiro Yoshida
  • Publication number: 20210046549
    Abstract: Provided is a soft magnetic powder capable of forming a powder magnetic core having a high magnetic permeability with a decreased oxygen content even when the particle size is small. There is provided a soft magnetic powder including Fe alloy containing Si which is a soft magnetic powder containing 0.1% to 15 mass % of Si, and having a product of D50 multiplied by [O] (D50×[O]) being 3.0 [?m·mass %] or less, wherein D50 represents a volume-based cumulative 50% particle size [?m] of the soft magnetic powder as measured by a laser diffraction particle size distribution analyzer, and [O] represents an oxygen content [mass %].
    Type: Application
    Filed: September 3, 2018
    Publication date: February 18, 2021
    Applicant: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Masahiro YOSHIDA, Yoshiyuki MICHIAKI, Kenichi INOUE
  • Patent number: 10919778
    Abstract: A method for making iron-based oxide magnetic particle powders having particular peak intensity and diffraction intensities, comprising neutralizing an aqueous solution containing a trivalent iron ion, alone or with a substituting metal (M), a step of adding hydroxycarboxylic acid to the neutralized solution to create a second solution including the hydroxycarboxylic acid D, another neutralizing step for the second solution, a coating step of silicon oxide coating iron oxyhydroxide with or without the substituted metal element found in the second neutralized solution, and heating the coated iron oxyhydroxide with or without the substituted metal element to form a silicon oxide coated iron oxide with or without the substituted metal element. After the second neutralization step, there is no water washing. As a result, the molar ratio D/(Fe+M) is between 0.125 and 1.0 and the silicon oxide coating can be uniform and the formation reaction of the hydroxide is not retarded.
    Type: Grant
    Filed: July 26, 2016
    Date of Patent: February 16, 2021
    Assignee: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Kenji Sakane, Tetsuya Kawahito
  • Patent number: 10915034
    Abstract: A carrier core material is represented by a composition formula MXFe3-XO4 (where M is at least one type of metal element selected from Mg, Mn, Ca, Ti, Cu, Zn and Ni, 0<X<1), in which part of M and/or Fe is substituted with Sr and formed of ferrite particles, and in the carrier core material, a Sr content is equal to or more than 2500 ppm but equal to or less than 12000 ppm, the amount of Sr eluted with pure water at a temperature of 25° C. is equal to or less than 50 ppm, an apparent density is equal to or more than 1.85 g/cm3 but equal to or less than 2.25 g/cm3 and magnetization ?1k when a magnetic field of 79.58×103 A/m (1000 oersteds) is applied is equal to or more than 63 Am2/kg but equal to or less than 75 Am2/kg.
    Type: Grant
    Filed: March 15, 2018
    Date of Patent: February 9, 2021
    Assignees: DOWA ELECTRONICS MATERIALS CO., LTD., DOWA IP CREATION CO., LTD.
    Inventor: Shou Ogawa
  • Patent number: 10903185
    Abstract: A bonding material includes: fine silver particles having an average primary particle diameter of 1 to 50 nm, 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 ?m each of the silver particles being coated with an organic compound, such as oleic acid; a solvent containing a primary alcohol solvent and a terpene alcohol solvent; and a dispersant containing a phosphoric acid ester dispersant (or a phosphoric acid ester dispersant and an acrylic resin dispersant), wherein the content of the fine silver particles is in the range of from 5 wt % to 30 wt %, and the content of the silver particles is in the range of from 60 wt % to 90 wt %, the total content of the fine silver particles and the silver particles being not less than 90 wt %, and wherein the bonding material further includes a sintering aid of a monocarboxylic acid having an ether bond.
    Type: Grant
    Filed: May 15, 2015
    Date of Patent: January 26, 2021
    Assignee: Dowa Electronics Materials Co., Ltd.
    Inventors: Keiichi Endoh, Koichi Yuzaki, Minami Nagaoka, Hiromasa Miyoshi, Satoru Kurita
  • Publication number: 20210020814
    Abstract: A method of manufacturing a semiconductor optical device of this disclosure includes the steps of forming an etch stop layer on an InP growth substrate, the etch stop layer having a thickness of 100 nm or less; and forming a semiconductor laminate on the etch stop layer by stacking a plurality of InGaAsP-based III-V group compound semiconductor layers containing at least In and P. Further, an intermediate article of a semiconductor optical device of the present disclosure includes an InP growth substrate; an etch stop layer formed on the InP growth substrate, the etch stop layer having a thickness of 100 nm or less; and a semiconductor laminate formed on the etch stop layer, including a plurality of InGaAsP-based III-V group compound semiconductor layers containing at least In and P stacked one another.
    Type: Application
    Filed: March 27, 2019
    Publication date: January 21, 2021
    Applicant: DOWA Electronics Materials Co., Ltd.
    Inventors: Yuta KOSHIKA, Yoshitaka KADOWAKI, Tetsuya IKUTA
  • Publication number: 20210012936
    Abstract: There is provided a magnetic material that has an excellent electromagnetic wave absorption performance in a wide frequency range even under low temperature and high temperature environments and that ensures the absorption performance, and provided a magnetic material as a mixture of a magnetic material having positive slope of change in coercive force dependent on temperature, and a magnetic material having negative slope of change in coercive force dependent on temperature.
    Type: Application
    Filed: February 14, 2019
    Publication date: January 14, 2021
    Applicants: The University of Tokyo, DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Shin-ichi OHKOSHI, Asuka NAMAI, Marie YOSHIKIYO, Masahiro GOTOH, Toshihiko UEYAMA, Takayuki YOSHIDA
  • Publication number: 20200381589
    Abstract: To provide a bonding-type semiconductor light-emitting device which has excellent reliabilities with smaller time deviations of the light output power and the forward voltage. A semiconductor light-emitting device 100 according to the present disclosure includes a conductive support substrate 80; a metal layer 60 containing a reflective metal provided on the conductive support substrate 10; a semiconductor laminate 30 formed from a stack of a plurality of InGaAsP group III-V compound semiconductor layers containing at least In and P provided on the reflective metal layer 60; an n-type InGaAs contact layer 20A provided on the semiconductor laminate 30; and an n-side electrode 93 provided on the n-type InGaAs contact layer 20A, wherein the center emission wavelength of light emitted from the semiconductor laminate 30 is 1000 to 2200 nm.
    Type: Application
    Filed: December 20, 2018
    Publication date: December 3, 2020
    Applicant: DOWA Electronics Materials Co., Ltd.
    Inventors: Jumpei YAMAMOTO, Tetsuya IKUTA
  • Patent number: 10828702
    Abstract: There is provided a silver powder which has a small average particle diameter and a small thermal shrinkage percentage, and a method for producing the same. While a molten metal of silver heated to a temperature (1292 to 1692° C.), which is higher than the melting point (962° C.) of silver by 330 to 730° C., is allowed to drop, a high-pressure water is sprayed onto the molten metal of silver (preferably at a water pressure of 90 to 160 MPa) to rapidly cool and solidify the molten metal of silver to powderize silver to produce a silver powder which has an average particle diameter of 1 to 6 ?m and a shrinkage percentage of not greater than 8% (preferably not greater than 7%) at 500° C., the product of the average particle diameter by the shrinkage percentage at 500° C. being 1 to 11 ?m·% (preferably 1.5 to 10.5 ?m·%).
    Type: Grant
    Filed: October 26, 2016
    Date of Patent: November 10, 2020
    Assignee: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Atsushi Ebara, Kenichi Inoue, Yoshiyuki Michiaki, Takahiro Yamada, Masahiro Yoshida
  • Patent number: 10833209
    Abstract: A conductive paste including: a conductive powder containing silver; an indium powder; a silver-tellurium-coated glass powder; a solvent; and an organic binder, wherein the silver-tellurium-coated glass powder is a silver-tellurium-coated glass powder including a tellurium-based glass powder containing tellurium in an amount of 20% by mass or more, and a coating layer on a surface of the tellurium-based glass powder, the coating layer containing silver and tellurium as a main component.
    Type: Grant
    Filed: September 5, 2017
    Date of Patent: November 10, 2020
    Assignee: DOWA Electronics Materials Co., Ltd.
    Inventors: Kenichi Harigae, Hiroshi Kamiga, Noriaki Nogami
  • Patent number: 10821558
    Abstract: There is provided an inexpensive bonding material, which can be easily printed on articles to be bonded to each other and which can suppress the generation of voids in the bonded portions of the articles to be bonded to each other, and a bonding method using the same. In a bonding material of a copper paste which contains a copper powder containing 0.3% by weight or less of carbon and having an average particle diameter of 0.1 to 1 ?m, and an alcohol solvent, such as a monoalcohol, a diol, a triol or a terpene alcohol, the content of the copper powder is in the range of from 80% by weight to 95% by weight, and the content of the alcohol solvent is in the range of from 5% by weight to 20% by weight.
    Type: Grant
    Filed: August 31, 2015
    Date of Patent: November 3, 2020
    Assignee: DOWA ELECTRONICS MATERIALS CO., LTD.
    Inventors: Keiichi Endoh, Hiromasa Miyoshi, Kimikazu Motomura, Satoru Kurita
  • Patent number: D915308
    Type: Grant
    Filed: November 19, 2019
    Date of Patent: April 6, 2021
    Assignee: DOWA Electronics Materials Co., Ltd.
    Inventor: Tsukasa Maruyama
  • Patent number: D915309
    Type: Grant
    Filed: November 19, 2019
    Date of Patent: April 6, 2021
    Assignee: DOWA Electronics Materials Co., Ltd.
    Inventor: Tsukasa Maruyama