Patents by Inventor Tsukasa Ohnishi
Tsukasa Ohnishi 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).
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Patent number: 8220692Abstract: An inexpensive lead-free solder which prevents the occurrence of tin pest at extremely low temperatures and which has good wettability and impact resistance has a composition consisting essentially of, in mass %, Cu: 0.5-0.8%, Bi: at least 0.1% and less than 1%, Ni: 0.02-0.04%, and a remainder of Sn.Type: GrantFiled: April 21, 2009Date of Patent: July 17, 2012Assignee: Senju Metal Industry Co., Ltd.Inventors: Tsukasa Ohnishi, Toshihiko Taguchi
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Patent number: 8216395Abstract: A lead-free solder alloy suitable for use in flow soldering of electronic components to printed wiring boards comprises 0.1-3 wt % of Cu, 0.001-0.1 wt % of P, optionally 0.001-0.1 wt % of Ge, and a balance of Sn. The solder alloy may further contain at least one of Ag and Sb in a total amount of at most 4 wt %, and/or at least one of Ni, Co, Fe, Mn, Cr, and Mo in a total amount of at most 0.5 wt % in order to strengthen the alloy, and/or at least one of Bi, In, and Zn in a total amount of at most 5 wt % in order to lower the melting point of the alloy.Type: GrantFiled: March 22, 2010Date of Patent: July 10, 2012Assignee: Senju Metal Industry Co., Ltd.Inventors: Osamu Munekata, Yoshitaka Toyoda, Tsukasa Ohnishi, Minoru Ueshima
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Publication number: 20110115084Abstract: 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: ApplicationFiled: March 3, 2009Publication date: May 19, 2011Inventors: Minoru Ueshima, Masayuki Suzuki, Yoshie Yamanaka, Shunsaku Yoshikawa, Tokuro Yamaki, Tsukasa Ohnishi
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Publication number: 20110089224Abstract: An inexpensive lead-free solder which prevents the occurrence of tin pest at extremely low temperatures and which has good wettability and impact resistance has a composition consisting essentially of, in mass %, Cu: 0.5-0.8%, Bi: at least 0.1% and less than 1%, Ni: 0.02-0.04%, and a remainder of Sn.Type: ApplicationFiled: April 21, 2009Publication date: April 21, 2011Inventors: Tsukasa Ohnishi, Toshihiko Taguchi
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Publication number: 20100297470Abstract: A lead-free solder alloy suitable for use in flow soldering of electronic components to printed wiring boards comprises 0.1-3 wt % of Cu, 0.001-0.1 wt % of P, optionally 0.001-0.1 wt % of Ge, and a balance of Sn. The solder alloy may further contain at least one of Ag and Sb in a total amount of at most 4 wt %, and/or at least one of Ni, Co, Fe, Mn, Cr, and Mo in a total amount of at most 0.5 wt % in order to strengthen the alloy, and/or at least one of Bi, In, and Zn in a total amount of at most 5 wt % in order to lower the melting point of the alloy.Type: ApplicationFiled: March 22, 2010Publication date: November 25, 2010Inventors: Osamu Munekata, Yoshitaka Toyoda, Tsukasa Ohnishi, Minoru Ueshima
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Patent number: 7682468Abstract: A lead-free solder alloy suitable for use in flow soldering of electronic components to printed wiring boards comprises 0.1-3 wt % of Cu, 0.001-0.1 wt % of P, optionally 0.001-0.1 wt % of Ge, and a balance of Sn. The solder alloy may further contain at least one element of Ag and Sb in a total amount of at most 4 wt %, and/or at least one element of Ni, Co, Fe, Mn, Cr, and Mo in a total amount of at most 0.5 wt % in order to strengthen the alloy, and/or at least one element of Bi, In, and Zn in a total amount of at most 5 wt % in order to lower the melting point of the alloy.Type: GrantFiled: August 10, 2007Date of Patent: March 23, 2010Assignee: Senju Metal Industry Co., Ltd.Inventors: Osamu Munekata, Yoshitaka Toyoda, Tsukasa Ohnishi, Minoru Ueshima
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Publication number: 20090301760Abstract: As BGA's and CSP's become widespread, the number of steps in soldering module boards to rigid printed wiring boards increases. A printed circuit board warps due to heating during reflow, so even if mounting is carried out at a temperature sufficiently exceeding the melting point of a solder alloy, there was a problem of the phenomenon of fusion defects in which the solder bumps of a module board of a CSP, a BGA, or the like and the mounting paste do not fuse or parts having leads and solder paste do not fuse, resulting in conduction defects. Means for Solving the Problem When soldering a module board to a rigid printed wiring board, a post-flux is applied to a module board before mounting, a solder paste is then applied to the rigid printed wiring board, and the module board is soldered.Type: ApplicationFiled: June 13, 2006Publication date: December 10, 2009Inventors: Masato Shimamura, Ko Inaba, Hiroshi Okada, Tsukasa Ohnishi
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Publication number: 20090232696Abstract: A lead-free solder alloy is provided which has improved impact resistance to dropping even after thermal aging and which is excellent with respect to solderability, occurrence of voids, and yellowing. A solder alloy according to the present invention consists essentially of, in mass percent, (1) Ag: 0.8-2.0%, (2) Cu: 0.05-0.3%, (3) at least one element selected from In: at least 0.01% and less than 0.1%, Ni; 0.01-0.04%, Co: 0.01-0.05%, and Pt: 0.01-0.1%, optionally (4) at least one element selected from Sb, Bi, Fe, Al, Zn, and P in a total amount of up to 0.1%, and a remainder of Sn and impurities.Type: ApplicationFiled: May 31, 2006Publication date: September 17, 2009Inventors: Tsukasa Ohnishi, Tokuro Yamaki, Daisuke Soma
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Publication number: 20080061117Abstract: A lead-free solder alloy suitable for use in flow soldering of electronic components to printed wiring boards comprises 0.1-3 wt % of Cu, 0.001-0.1 wt % of P, optionally 0.001-0.1 wt % of Ge, and a balance of Sn. The solder alloy may further contain at least one element of Ag and Sb in a total amount of at most 4 wt %, and/or at least one element of Ni, Co, Fe, Mn, Cr, and Mo in a total amount of at most 0.5 wt % in order to strengthen the alloy, and/or at least one element of Bi, In, and Zn in a total amount of at most 5 wt % in order to lower the melting point of the alloy.Type: ApplicationFiled: August 10, 2007Publication date: March 13, 2008Inventors: Osamu Munekata, Yoshitaka Toyoda, Tsukasa Ohnishi, Minoru Ueshima
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Patent number: 7338567Abstract: A lead-free solder alloy suitable for use in flow soldering of electronic components to printed wiring boards comprises 0.1-3 wt % of Cu, 0.001-0.1 wt % of P, optionally 0.001-0.1 wt % of Ge, and a balance of Sn. The solder alloy may further contain at least one element of Ag and Sb in a total amount of at most 4 wt %, and/or at least one element of Ni, Co, Fe, Mn, Cr, and Mo in a total amount of at most 0.5 wt % in order to strengthen the alloy, and/or at least one element of Bi, In, and Zn in a total amount of at most 5 wt % in order to lower the melting point of the alloy.Type: GrantFiled: September 22, 2003Date of Patent: March 4, 2008Assignee: Senju Metal Industry Co., Ltd.Inventors: Osamu Munekata, Yoshitaka Toyoda, Tsukasa Ohnishi, Minoru Ueshima
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Publication number: 20070243098Abstract: [Problem]Mobile electronic equipment is often dropped during use or transport, and the soldered joints of electronic parts sometimes peel off due to the impact when dropped. In addition, they undergo heat cycles in which internal coils, resistors, and the like generate heat and soldered joints increase in temperature during operation of electronic equipment and cool off during periods of non-use. With a conventional Sn—Ag base lead-free solder, the impact resistance and resistance to heat cycles of minute portions such as solder bumps were not adequate. The present invention provides a lead-free solder alloy, bumps of which have excellent impact resistance and resistance to heat cycles. Means for Solving the Problem The present invention is a lead-free solder alloy comprising 0.1—less than 2.0 mass % of Ag, 0.01-0.1 mass % of Cu, 0.005-0.1 mass % of Zn, and a remainder of Sn, to which Ga, Ge, or P may be added, and to which Ni or Co may be further added.Type: ApplicationFiled: July 29, 2004Publication date: October 18, 2007Inventors: Tsukasa Ohnishi, Tokuro Yamaki, Masazumi Amagai, Masako Watanabe
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Patent number: 7282175Abstract: A lead-free solder includes 0.05-5 mass % of Ag, 0.01-0.5 mass % of Cu, at least one of P, Ge, Ga, Al, and Si in a total amount of 0.001-0.05 mass %, and a remainder of Sn. One or more of a transition element for improving resistance to heat cycles, a melting point lowering element such as Bi, In, or Zn, and an element for improving impact resistance such as Sb may be added.Type: GrantFiled: April 15, 2004Date of Patent: October 16, 2007Assignee: Senju Metal Industry Co., Ltd.Inventors: Masazumi Amagai, Masako Watanabe, Kensho Murata, Yoshitaka Toyoda, Minoru Ueshima, Tsukasa Ohnishi, Takeshi Tashima, Daisuke Souma, Takahiro Roppongi, Hiroshi Okada
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Patent number: 7282174Abstract: The present invention provides a Sn—Zn based lead-free solder which can prevent peeling of solder from soldered portions even after the passage of long periods after soldering of portions to be soldered made of Cu. A Sn—Zn based lead-free solder according to the present invention comprises 5-10 mass percent of Zn, a total of 0.005-1.0 mass percent of at least one substance selected from the group consisting of Au, Pt, Pd, Fe, and Sb, optionally a total of at most 15 mass percent of at least one substance selected from the group consisting of Bi and In, and a remainder of Sn. This Sn—Zn based lead-free solder can be made into a solder paste using a rosin flux containing a halide such as an amine hydrochloride as an activator.Type: GrantFiled: October 31, 2003Date of Patent: October 16, 2007Assignees: Senju Metal Industry Co., Ltd., Matsushita Electric Industrial Co., LtdInventors: Masahiko Hirata, Hisahiko Yoshida, Takashi Nagashima, Toshihiko Taguchi, Yoshitaka Toyoda, Tsukasa Ohnishi
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Patent number: 7172726Abstract: A lead-free solder which is significantly less susceptible to copper leaching when used in a molten state in which coil ends of copper wire are dipped comprises 1.5–8 mass % of Cu, 0.01–2 mass % of Co, optionally 0.01–1 mass % of Ni, and a remainder of Sn and has a liquidus temperature of 420° C. or below. The solder may further comprise at least one oxidation-inhibiting element selected from the group consisting of P, Ge, and Ga in a total amount of 0.001–0.5 mass %, and/or Ag in an amount of 0.05–2 mass % as a wettability-improving element.Type: GrantFiled: October 10, 2003Date of Patent: February 6, 2007Assignee: Senju Metal Industry Co., Ltd.Inventor: Tsukasa Ohnishi
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Publication number: 20060102690Abstract: The present invention provides a Sn—Zn based lead-free solder which can prevent peeling of solder from soldered portions even after the passage of long periods after soldering of portions to be soldered made of Cu. A Sn—Zn based lead-free solder according to the present invention comprises 5-10 mass percent of Zn, a total of 0.005-1.0 mass percent of at least one substance selected from the group consisting of Au, Pt, Pd, Fe, and Sb, optionally a total of at most 15 mass percent of at least one substance selected from the group consisting of Bi and In, and a remainder of Sn. This Sn—Zn based lead-free solder can be made into a solder paste using a rosin flux containing a halide such as an amine hydrochloride as an activator.Type: ApplicationFiled: October 31, 2003Publication date: May 18, 2006Inventors: Masahiko Hirata, Hisahiko Yoshida, Takashi Nagashima, Toshihiko Taguchi, Yoshitaka Toyoda, Tsukasa Ohnishi
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Patent number: 7029542Abstract: A lead-free solder alloy comprises 1.0–5.0 wt % Ag, 0.01–0.5 wt % Ni, one or both of (a) 0.001–0.05 wt % Co and (b) at least one of P, Ge, and Ga in a total amount of 0.001–0.05 wt %, and a remainder of Sn. The solder can form solder bumps which have a high bonding strength and which do not undergo yellowing after soldering.Type: GrantFiled: July 8, 2003Date of Patent: April 18, 2006Assignee: Senju Metal Industry Co., Ltd.Inventors: Masazumi Amagai, Masako Watanabe, Kensho Murata, Osamu Munekata, Yoshitaka Toyoda, Minoru Ueshima, Tsukasa Ohnishi, Hiroshi Okada
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Publication number: 20050036902Abstract: A lead-free solder alloy comprises 1.0-5.0 wt % Ag, 0.01-0.5 wt % Ni, one or both of (a) 0.001-0.05 wt % Co and (b) at least one of P, Ge, and Ga in a total amount of 0.001-0.05 wt %, and a remainder of Sn. The solder can form solder bumps which have a high bonding strength and which do not undergo yellowing after soldering.Type: ApplicationFiled: July 8, 2003Publication date: February 17, 2005Inventors: Masazumi Amagai, Masako Watanabe, Osamu Munekata, Yoshitaka Toyoda, Minoru Ueshima, Tsukasa Ohnishi, Hiroshi Okada
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Publication number: 20040262779Abstract: A lead-free solder includes 0.05-5 mass % of Ag, 0.01-0.5 mass % of Cu, at least one of P, Ge, Ga, Al, and Si in a total amount of 0.001-0.05 mass %, and a remainder of Sn. One or more of a transition element for improving resistance to heat cycles, a melting point lowering element such as Bi, In, or Zn, and an element for improving impact resistance such as Sb may be added.Type: ApplicationFiled: April 15, 2004Publication date: December 30, 2004Inventors: Masazumi Amagai, Masako Watanabe, Kensho Murata, Yoshitaka Toyoda, Minoru Ueshima, Tsukasa Ohnishi, Takeshi Tashima, Daisuke Souma, Takahiro Roppongi, Hiroshi Okada
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Publication number: 20040115088Abstract: A lead-free solder which is significantly less susceptible to copper leaching when used in a molten state in which coil ends of copper wire are dipped comprises 1.5-8 mass % of Cu, 0.01-2 mass % of Co, optionally 0.01-1 mass % of Ni, and a remainder of Sn and has a liquidus temperature of 420° C. or below. The solder may further comprise at least one oxidation-inhibiting element selected from the group consisting of P, Ge, and Ga in a total amount of 0.001-0.5 mass %, and/or Ag in an amount of 0.05-2 mass % as a wettability-improving element.Type: ApplicationFiled: October 10, 2003Publication date: June 17, 2004Inventor: Tsukasa Ohnishi
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Publication number: 20040062679Abstract: A lead-free solder alloy suitable for use in flow soldering of electronic components to printed wiring boards comprises 0.1-3 wt % of Cu, 0.001-0.1 wt % of P, optionally 0.001-0.1 wt % of Ge, and a balance of Sn. The solder alloy may further contain at least one element of Ag and Sb in a total amount of at most 4 wt %, and/or at least one element of Ni, Co, Fe, Mn, Cr, and Mo in a total amount of at most 0.5 wt % in order to strengthen the alloy, and/or at least one element of Bi, In, and Zn in a total amount of at most 5 wt % in order to lower the melting point of the alloy.Type: ApplicationFiled: September 22, 2003Publication date: April 1, 2004Applicant: Senju Metal Industry Co., Ltd.Inventors: Osamu Munekata, Yoshitaka Toyoda, Tsukasa Ohnishi, Minoru Ueshima