Patents by Inventor Shunsaku Yoshikawa

Shunsaku Yoshikawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10076808
    Abstract: A lead-free solder alloy capable of forming solder joints in which electromigration and an increase in resistance during electric conduction at a high current density are suppressed has an alloy composition consisting essentially of 1.0-13.0 mass % of In, 0.1-4.0 mass % of Ag, 0.3-1.0 mass % of Cu, a remainder of Sn. The solder alloy has excellent tensile properties even at a high temperature exceeding 100° C. and can be used not only for CPUs but also for power semiconductors.
    Type: Grant
    Filed: August 5, 2013
    Date of Patent: September 18, 2018
    Assignee: Senju Metal Industry Co., Ltd.
    Inventors: Tsukasa Ohnishi, Shunsaku Yoshikawa, Ken Tachibana, Yoshie Yamanaka, Hikaru Nomura, Kyu-oh Lee
  • Patent number: 9987710
    Abstract: A solder paste whereby metal does not flow out of a joint during a second or subsequent reflow heating stage. The solder paste excels in terms of temporal stability and exhibits high joint strength at room temperature and at high temperatures. The solder paste comprises a powdered metal component and a flux component, the powdered metal component comprising: 10-70 mass % of a powdered intermetallic compound comprising copper and tin and 30-90 mass % of a solder powder including tin as a main component. Neither the powdered intermetallic compound nor the solder powder contains a copper-only phase, inhibiting the elution of copper ions into the flux.
    Type: Grant
    Filed: March 28, 2014
    Date of Patent: June 5, 2018
    Assignee: Senju Metal Industry Co., Ltd.
    Inventors: Motoki Koroki, Shunsaku Yoshikawa, Sakie Okada, Taro Itoyama, Hideyuki Komuro, Naoko Hirai, Keitaro Shimizu
  • Publication number: 20180005970
    Abstract: A lead-free solder ball is provided which suppresses interfacial peeling in a bonding interface of a solder ball, fusion defects which develop between the solder ball and solder paste, and which can be used both with Ni electrodes plated with Au or the like and Cu electrodes having a water-soluble preflux applied atop Cu. The lead-free solder ball for electrodes of BGAs or CSPs consists of 1.6-2.9 mass % of Ag, 0.7-0.8 mass % of Cu, 0.05-0.08 mass % of Ni, and a remainder of Sn. It has excellent resistance to thermal fatigue and to drop impacts regardless of the type of electrodes of a printed circuit board to which it is bonded, which are Cu electrodes or Ni electrodes having Au plating or Au/Pd plating as surface treatment.
    Type: Application
    Filed: July 6, 2017
    Publication date: January 4, 2018
    Inventors: Yoshie Yamanaka, Ken Tachibana, Shunsaku Yoshikawa, Hikaru Nomura
  • Publication number: 20180001426
    Abstract: Provided is a lead-free solder alloy that has excellent tensile strength and ductility, does not deform after heat cycles, and does not crack. The In and Bi content are optimized and the Sb and Ni content are adjusted. As a result, this solder alloy has an alloy composition including, by mass, 1.0 to 7.0% of In, 1.5 to 5.5% of Bi, 1.0 to 4.0% of Ag, 0.01 to 0.2% of Ni, and 0.01 to 0.15% of Sb, with the remainder made up by Sn.
    Type: Application
    Filed: June 5, 2017
    Publication date: January 4, 2018
    Inventors: Masayuki SUZUKI, Naoko IZUMITA, Shunsaku YOSHIKAWA, Ken TACHIBANA, Rei FUJIMAKI, Hikaru NOMURA
  • Patent number: 9844837
    Abstract: By using a solder alloy consisting essentially of 0.2-1.2 mass % of Ag, 0.6-0.9 mass % of Cu, 1.2-3.0 mass % of Bi, 0.02-1.0 mass % of Sb, 0.01-2.0 mass % of In, and a remainder of Sn, it is possible to obtain portable devices having excellent resistance to drop impact and excellent heat cycle properties without developing thermal fatigue even when used in a high-temperature environment such as inside a vehicle heated by the sun or in a low-temperature environment such as outdoors in snowy weather.
    Type: Grant
    Filed: March 23, 2012
    Date of Patent: December 19, 2017
    Assignee: Senju Metal Industry Co., Ltd.
    Inventors: Masato Shimamura, Tsukasa Ohnishi, Mitsuhiro Kosai, Kazuyori Takagi, Tomoko Nonaka, Masayuki Suzuki, Toru Hayashida, Seiko Ishibashi, Shunsaku Yoshikawa, Yoshie Yamanaka
  • Patent number: 9837757
    Abstract: With the increasing density of in-vehicle electronic circuits, not only conventional cracks at bonding interfaces such as between the substrate and the solder attachment site or a component and the solder attachment site but also novel cracking problems of cracks occurring in the Sn matrix in the interior of the bonded solder have appeared. To solve the above problem, a lead-free solder alloy with 1-4 mass % Ag, 0.6-0.8 mass % Cu, 1-5 mass % Sb, 0.01-0.2 mass % Ni and the remainder being Sn is used. A solder alloy, which not only can withstand harsh temperature cycling characteristics from low temperatures of ?40° C. to high temperatures of 125° C. but can also withstand external forces that occur when riding up on a curb or colliding with a vehicle in front for long periods, and an in-vehicle electronic circuit device using the solder alloy can thereby be obtained.
    Type: Grant
    Filed: April 3, 2014
    Date of Patent: December 5, 2017
    Assignee: SENJU METAL INDUSTRY CO., LTD.
    Inventors: Shunsaku Yoshikawa, Naoko Hirai, Ken Tachibana, Yoshie Tachibana
  • Patent number: 9808890
    Abstract: A solder alloy has an alloy composition containing Zn of 3 through 25 mass %, Ti of 0.002 through 0.25 mass %, Al of 0.002 through 0.25 mass % and balance of Sn, a solder joint made of the solder alloy, and a jointing method using the solder alloy.
    Type: Grant
    Filed: April 17, 2013
    Date of Patent: November 7, 2017
    Assignee: Senju Metal Industry Co., Ltd.
    Inventors: Hikaru Nomura, Shunsaku Yoshikawa
  • Patent number: 9780055
    Abstract: A lead-free solder ball is provided which suppresses interfacial peeling in a bonding interface of a solder ball, fusion defects which develop between the solder ball and solder paste, and which can be used both with Ni electrodes plated with Au or the like and Cu electrodes having a water-soluble preflux applied atop Cu. The lead-free solder ball for electrodes of BGAs or CSPs consists of 1.6-2.9 mass % of Ag, 0.7-0.8 mass % of Cu, 0.05-0.08 mass % of Ni, and a remainder of Sn. It has excellent resistance to thermal fatigue and to drop impacts regardless of the type of electrodes of a printed circuit board to which it is bonded, which are Cu electrodes or Ni electrodes having Au plating or Au/Pd plating as surface treatment. The composition may include at least one element selected from Fe, Co, and Pt in a total amount of 0.003-0.1 mass % or at least one element selected from Bi, In, Sb, P, and Ge in a total amount of 0.003-0.1 mass %.
    Type: Grant
    Filed: June 30, 2012
    Date of Patent: October 3, 2017
    Assignee: Senju Metal Industry Co., Ltd.
    Inventors: Yoshie Yamanaka, Ken Tachibana, Shunsaku Yoshikawa, Hikaru Nomura
  • Publication number: 20170274481
    Abstract: Provided is a lead-free solder alloy for terminal preliminary plating, by which the separation property when pulling up the terminals from molten solder is improved. The lead-free solder alloy for terminal preliminary plating contains 4 mass % or more and 6 mass % or less of Cu, 0.1 mass % or more and 0.2 mass % or less of Ni, 0.01 mass % or more and 0.04 mass % or less of Ga, 0.004 mass % or more and 0.03 mass % or less of P, and a remainder of Sn, a total amount of Ga and P being 0.05 mass % or less. Its tension in a melted condition by heating in soldering temperature is 200 dyn/cm or less.
    Type: Application
    Filed: September 4, 2015
    Publication date: September 28, 2017
    Inventor: Shunsaku Yoshikawa
  • Patent number: 9773721
    Abstract: A lead-free solder which can reduce the occurrence of voids and a connecting member which uses the solder and has excellent adhesion, bonding strength, and workability are provided. The lead-free solder alloy contains Sn: 0.1-3% and/or Bi: 0.1-2%, and a remainder of In and unavoidable impurities and has the effect of suppressing the occurrence of voids at the time of soldering. The connecting member is prepared by melting the lead-free solder alloy, immersing a metal substrate in the melt, and applying ultrasonic vibrations to the molten lead-free solder alloy and the metal substrate to form a lead-free solder alloy layer on the surface of the metal substrate. A heat sink and a package are soldered to each other through this connecting member by reflow heating in the presence of flux.
    Type: Grant
    Filed: June 25, 2014
    Date of Patent: September 26, 2017
    Assignee: SENJU METAL INDUSTRY CO., LTD.
    Inventors: Shunsaku Yoshikawa, Yoshie Yamanaka, Tsukasa Ohnishi, Seiko Ishibashi, Koji Watanabe, Hiroki Ishikawa, Yutaka Chiba
  • Publication number: 20170151636
    Abstract: A solder alloy has an alloy composition consisting of, in mass %: Bi: 0.1 to 0.8%; Ag: 0 to 0.3%; Cu: 0 to 0.7%; P: 0.001 to 0.1%, with the balance being Sn. A total amount of Ag and Bi is from 0.3 to 0.8% in the alloy composition.
    Type: Application
    Filed: November 28, 2016
    Publication date: June 1, 2017
    Applicant: SENJU METAL INDUSTRY CO., LTD.
    Inventors: Shunsaku YOSHIKAWA, Hikaru NOMURA
  • Patent number: 9597753
    Abstract: A solder paste whereby metal does not flow out of a joint during a second or subsequent reflow heating stage. The solder paste excels in terms of temporal stability and exhibits high joint strength at room temperature and at high temperatures. The solder paste comprises a powdered metal component and a flux component, the powdered metal component comprising: 10-70 mass % of a powdered intermetallic compound comprising copper and tin and 30-90 mass % of a solder powder including tin as a main component. Neither the powdered intermetallic compound nor the solder powder contains a copper-only phase, inhibiting the elution of copper ions into the flux.
    Type: Grant
    Filed: March 28, 2014
    Date of Patent: March 21, 2017
    Assignee: Senju Metal Industry Co., Ltd.
    Inventors: Motoki Koroki, Shunsaku Yoshikawa, Sakie Okada, Taro Itoyama, Hideyuki Komuro, Naoko Hirai, Keitaro Shimizu
  • Publication number: 20160158896
    Abstract: A solder paste whereby metal does not flow out of a joint during a second or subsequent reflow heating stage. The solder paste excels in terms of temporal stability and exhibits high joint strength at room temperature and at high temperatures. The solder paste comprises a powdered metal component and a flux component, the powdered metal component comprising the following: 10-70 mass % of a powdered intermetallic compound comprising copper and tin and 30-90 mass % of a solder powder including tin as a main component. Neither the powdered intermetallic compound nor the solder powder contains a copper-only phase, inhibiting the elution of copper ions into the flux.
    Type: Application
    Filed: March 28, 2014
    Publication date: June 9, 2016
    Applicant: SENJU METAL INDUSTRY CO., LTD.
    Inventors: Motoki Koroki, Shunsaku Yoshikawa, Sakie Okada, Taro Itoyama, Hideyuki Komuro, Naoko Hirai, Keitaro Shimizu
  • Publication number: 20160158897
    Abstract: A solder paste whereby metal does not flow out of a joint during a second or subsequent reflow heating stage. The solder paste exhibits high joint strength at room temperature and at high temperatures, excels in terms of temporal stability, exhibits minimal void formation, and can form highly cohesive joints. The solder paste comprises a powdered metal component and a flux component, the powdered metal component comprising: a powdered intermetallic compound that comprises copper and tin and has metal barrier layers covering the surfaces thereof and a solder powder including tin as a main component. Neither the powdered intermetallic compound nor the solder powder contains a copper-only phase, inhibiting the elution of copper ions into the flux.
    Type: Application
    Filed: March 28, 2014
    Publication date: June 9, 2016
    Applicant: SENJU METAL INDUSTRY CO., LTD.
    Inventors: Motoki Koroki, Shunsaku Yoshikawa, Sakie Okada, Taro Itoyama, Hideyuki Komuro, Naoko Hirai, Keitaro Shimizu
  • Publication number: 20160056570
    Abstract: With the increasing density of in-vehicle electronic circuits, not only conventional cracks at bonding interfaces such as between the substrate and the solder attachment site or a component and the solder attachment site but also novel cracking problems of cracks occurring in the Sn matrix in the interior of the bonded solder have appeared. To solve the above problem, a lead-free solder alloy with 1-4 mass % Ag, 0.6-0.8 mass % Cu, 1-5 mass % Sb, 0.01-0.2 mass % Ni and the remainder being Sn is used. A solder alloy, which not only can withstand harsh temperature cycling characteristics from low temperatures of ?40° C. to high temperatures of 125° C. but can also withstand external forces that occur when riding up on a curb or colliding with a vehicle in front for long periods, and an in-vehicle electronic circuit device using the solder alloy can thereby be obtained.
    Type: Application
    Filed: April 3, 2014
    Publication date: February 25, 2016
    Inventors: Shunsaku YOSHIKAWA, Naoko HIRAI, Ken TACHIBANA, Yoshie TACHIBANA
  • Publication number: 20150328722
    Abstract: Provided is a lead-free solder alloy that has excellent tensile strength and ductility, does not deform after heat cycles, and does not crack. The In and Bi content are optimized and the Sb and Ni content are adjusted. As a result, this solder alloy has an alloy composition including, by mass, 1.0 to 7.0% of In, 1.5 to 5.5% of Bi, 1.0 to 4.0% of Ag, 0.01 to 0.2% of Ni, and 0.01 to 0.15% of Sb, with the remainder made up by Sn.
    Type: Application
    Filed: December 18, 2012
    Publication date: November 19, 2015
    Inventors: Masayuki SUZUKI, Naoko HIRAI, Shunsaku YOSHIKAWA, Ken TACHIBANA, Rei FUJIMAKI, Hikaru NOMURA
  • Publication number: 20150221606
    Abstract: A lead-free solder ball is provided which suppresses interfacial peeling in a bonding interface of a solder ball, fusion defects which develop between the solder ball and solder paste, and which can be used both with Ni electrodes plated with Au or the like and Cu electrodes having a water-soluble preflux applied atop Cu. The lead-free solder ball for electrodes of BGAs or CSPs consists of 1.6-2.9 mass % of Ag, 0.7-0.8 mass % of Cu, 0.05-0.08 mass % of Ni, and a remainder of Sn. It has excellent resistance to thermal fatigue and to drop impacts regardless of the type of electrodes of a printed circuit board to which it is bonded, which are Cu electrodes or Ni electrodes having Au plating or Au/Pd plating as surface treatment. The composition may include at least one element selected from Fe, Co, and Pt in a total amount of 0.003-0.1 mass % or at least one element selected from Bi, In, Sb, P, and Ge in a total emount of 0.003-0.1 mass %.
    Type: Application
    Filed: June 30, 2012
    Publication date: August 6, 2015
    Applicant: SENJU METAL INDUSTRY CO., LTD.
    Inventors: Yoshie Yamanaka, Ken Tachibana, Shunsaku Yoshikawa, Hikaru Nomura
  • Publication number: 20150086263
    Abstract: A solder alloy has an alloy composition containing Zn of 3 through 25 mass %, Ti of 0.002 through 0.25 mass %, Al of 0.002 through 0.25 mass % and balance of Sn, a solder joint made of the solder alloy, and a jointing method using the solder alloy.
    Type: Application
    Filed: April 17, 2013
    Publication date: March 26, 2015
    Inventors: Hikaru Nomura, Shunsaku Yoshikawa
  • Patent number: 8975757
    Abstract: Solder used for flip chip bonding inside a semiconductor package was a Sn—Pb solder such as a Pb-5Sn composition. Lead-free solders which have been studied are hard and easily form intermetallic compounds with Sn, so they were not suitable for a flip chip connection structure inside a semiconductor package, which requires stress relaxation properties. This problem is eliminated by a flip chip connection structure inside a semiconductor package using a lead-free solder which is characterized by consisting essentially of 0.01-0.5 mass percent of Ni and a remainder of Sn. 0.3-0.9 mass percent of Cu and 0.001-0.01 mass percent of P may be added to this solder composition.
    Type: Grant
    Filed: March 3, 2009
    Date of Patent: March 10, 2015
    Assignee: Senju Metal Industry Co., Ltd.
    Inventors: Minoru Ueshima, Masayuki Suzuki, Yoshie Yamanaka, Shunsaku Yoshikawa, Tokuro Yamaki, Tsukasa Ohnishi
  • Publication number: 20150037088
    Abstract: A lead-free solder alloy capable of forming solder joints in which electromigration and an increase in resistance during electric conduction at a high current density are suppressed has an alloy composition consisting essentially of 1.0-13.0 mass % of In, 0.1-4.0 mass % of Ag, 0.3-1.0 mass % of Cu, a remainder of Sn. The solder alloy has excellent tensile properties even at a high temperature exceeding 100° C. and can be used not only for CPUs but also for power semiconductors.
    Type: Application
    Filed: August 5, 2013
    Publication date: February 5, 2015
    Applicant: Senju Metal Industry Co., Ltd.
    Inventors: Tsukasa Ohnishi, Shunsaku Yoshikawa, Ken Tachibana, Yoshie Yamanaka, Hikaru Nomura, Kyu-oh Lee