Copper Containing Patents (Class 420/560)
  • Patent number: 6843862
    Abstract: A substantially lead-free solder with enhanced properties comprises from 88.5% to 93.5% tin; from 3.5% to 4.5% silver; from 2.0% to 6.0% indium; and from 0.3% to 1.0% copper. The solder may also comprise up to 0.5% of an anti-oxidant or anti-skinning additive. A solder embodying the invention finds particular utility in wave-soldering processes where it may be used as a direct replacement for conventional tin/lead solder.
    Type: Grant
    Filed: August 17, 2001
    Date of Patent: January 18, 2005
    Assignees: Quantum Chemical Technologies (Singapore) Pte Ltd, Singapore Asahi Chemical and Solder Industries Pte Ltd
    Inventors: Kai Hwa Chew, Wei Chih Pan
  • Patent number: 6837947
    Abstract: This invention discloses a lead-free Sn—Zn—Al—Ag solder alloy, which is composed of 7-10 wt % of Zn, up to 0.5 wt % of Al, up to 4.0 wt % of Ag, and the balance of Sn; and a lead-free Sn—Zn—Al—Ag—Ga solder alloy, which is composed of 7-10 wt % of Zn, up to 0.5 wt % of Al, up to 4.0 wt % of Ag, up to 4.0 wt % of Ga; and the balance of Sn. The lead-free solder alloys of the present invention have better tensile strength and elongation than the conventional Sn—Pb solder alloys. In addition, the lead-free solder alloys of the present invention have a melting point lower than 200° C., which is close to the 183.5° C. of an eutectic Sn—Pb alloy.
    Type: Grant
    Filed: January 15, 2002
    Date of Patent: January 4, 2005
    Assignee: National Cheng-Kung University
    Inventors: Kwang-Lung Lin, Kang-I Chen, Shou-Chang Cheng, Jia-Wei Huang
  • Publication number: 20040262779
    Abstract: 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: Application
    Filed: April 15, 2004
    Publication date: December 30, 2004
    Inventors: Masazumi Amagai, Masako Watanabe, Kensho Murata, Yoshitaka Toyoda, Minoru Ueshima, Tsukasa Ohnishi, Takeshi Tashima, Daisuke Souma, Takahiro Roppongi, Hiroshi Okada
  • Publication number: 20040258556
    Abstract: According to one aspect of the invention, a modified Sn—Ag—Cu, lead-free solder alloy is disclosed. The alloy comprises an additive element selected from the group consisting of Au, Ni, Pd, Fe, Co, Zn, Cr and combinations thereof, present in the alloy in an amount effect to form an intermetallic interface between the alloy a substrate, the intermetallic interface having a composite structure without scallop formation and including Sn islands.
    Type: Application
    Filed: October 2, 2003
    Publication date: December 23, 2004
    Applicants: Nokia Corporation, Board of Regents, University of Texas System
    Inventors: Choong-Un Kim, Jae-Yong Park, Rajendra R. Kabade, Ted Carper, Steven Dunford, Viswanadham Puligandla
  • Patent number: 6805974
    Abstract: A solder composition and associated method of formation. The solder composition comprises a substantially lead-free alloy that includes tin (Sn), silver (Ag), and copper. The tin has a weight percent concentration in the alloy of at least about 90%. The silver has a weight percent concentration X in the alloy. X is sufficiently small that formation of Ag3Sn plates is substantially suppressed when the alloy in a liquefied state is being solidified by being cooled to a lower temperature at which the solid Sn phase is nucleated. This lower temperature corresponds to an undercooling &dgr;T relative to the eutectic melting temperature of the alloy. Alternatively, X may be about 4.0% or less, wherein the liquefied alloy is cooled at a cooling rate that is high enough to substantially suppress Ag3Sn plate formation in the alloy. The copper has a weight percent concentration in the alloy not exceeding about 1.5%.
    Type: Grant
    Filed: February 15, 2002
    Date of Patent: October 19, 2004
    Assignee: International Business Machines Corporation
    Inventors: Won K. Choi, Charles C. Goldsmith, Timothy A. Gosselin, Donald W. Henderson, Sung K. Kang, Karl J. Puttlitz, Sr., Da-Yuan Shih
  • Patent number: 6774490
    Abstract: An electronic equipment is capable of improving falling down shock resistance or impact resistance in an electronic equipment and of improving reliability of a solder joint in a semiconductor device die-bonded Si chip or the like to which thermal shock causing large deformation may act, bump mounting of BGA, CSP, WPP, flip-chip and so forth, a power module acting large stress and so forth. The electronic equipment has a circuit board and an electronic parts to be electrically connected to an electrode of the circuit board. The electrode of the circuit board and an electrode of the electronic part are connected by soldering using a lead free solder consisted of Cu: 0-2.0 mass %, In: 0.1-10 mass %, and Sn: remaining amount.
    Type: Grant
    Filed: March 25, 2003
    Date of Patent: August 10, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Tasao Soga, Hanae Shimokawa, Tetsuya Nakatsuka, Masato Nakamura, Yuji Fujita, Toshiharu Ishida, Masahide Okamoto, Koji Serizawa, Toshihiro Hachiya, Hideki Mukuno
  • Publication number: 20040126270
    Abstract: Prevented is disconnection, and generation of the bridging effect which causes short circuits between terminals, when electric wire having an insulating coating and terminals are soldered together, in electronic components which are constituted using electric wire having an insulating coating, the core wire thereof being copper or a copper alloy, and in which electronic components distances between neighboring terminals are narrow.
    Type: Application
    Filed: June 3, 2003
    Publication date: July 1, 2004
    Inventors: Koichi Izumida, Yuki Takano, Hitoshi Abe, Toshiyuki Moribayashi, Koichi Hagio, Junichi Takenaka
  • Publication number: 20040126269
    Abstract: A solder which can form a soldered joint of good bonding strength on a Ni layer containing a small amount of P formed from electroless Ni plating with a P-containing plating solution comprises 60-64 mass % of Sn, 0.002-0.01 mass % of P, 0.04-0.3 mass % of Cu, and a remainder of Pb. The solder is particularly suitable for forming a solder bump on a Cu electrode which has been coated with Ni by electroless plating.
    Type: Application
    Filed: September 24, 2003
    Publication date: July 1, 2004
    Inventors: Iwao Nozawa, Takashi Hori, Daisuke Soma, Takahiro Roppongi
  • Publication number: 20040112474
    Abstract: Lead-free solder balls having a smooth surface and no shrinkage cavities or wrinkles are made of a lead-free solder which comprises, by atomic percent, 3%-6% of Ag, 1%-4% of Cu, 0.01%-2% of at least one element of the iron group and preferably Co, optionally 0.04%-4% of P, and a balance of Sn.
    Type: Application
    Filed: October 15, 2003
    Publication date: June 17, 2004
    Inventors: Rikiya Kato, Shinichi Nomoto, Hiroshi Okada
  • Publication number: 20040115088
    Abstract: 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: Application
    Filed: October 10, 2003
    Publication date: June 17, 2004
    Inventor: Tsukasa Ohnishi
  • Publication number: 20040062679
    Abstract: 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: Application
    Filed: September 22, 2003
    Publication date: April 1, 2004
    Applicant: Senju Metal Industry Co., Ltd.
    Inventors: Osamu Munekata, Yoshitaka Toyoda, Tsukasa Ohnishi, Minoru Ueshima
  • Patent number: 6702176
    Abstract: A solder consists essentially of 1.0% to 4.0% of Ag by mass, 0.2% to 1.3% of Cu by mass, 0.02% to 0.06% of Co by mass, and the remaining of Sn and inevitable impurities.
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: March 9, 2004
    Assignees: NEC Toppan Circuit Solutions, INC, Solder Coat Co., Ltd.
    Inventors: Toshihide Ito, Shiro Hara
  • Patent number: 6692691
    Abstract: A Pb-free soldering alloy that does not include any Pb is provided. The soldering alloy prevents Cu present in a printed-circuit board from combining with Ni in the soldering alloy at the soldered part, prevents Cu from precipitating and diffusing in the soldering alloy, suppresses the generation of fine cracks at the soldered part and increases the mechanical strength of the soldered part. The Pb-free soldering alloy contains 3.5 to 6.0 wt. % Ag, 0.001 to 1.0 wt. % Ni and Sn for the balance.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: February 17, 2004
    Assignees: Nihon Alimit Co., Ltd., Matsushita Electric Industrial Co., Ltd.
    Inventors: Tadashi Sawamura, Hisashi Komiya, Tsuguo Inazawa, Fujio Nakagawa
  • Patent number: 6689488
    Abstract: A lead-free solder, which contains from 1.0 to 3.5% of Ag, from 0.1 to 0.7% of Cu, and from 0.1 to 2.0% of In, the balance consisting of unavoidable impurities and Sn, is appropriate for ball-grid array (BGA). The solute Cu suppresses growth of intermetallic compound formed at the interface between the bulk of solder and a Ni or Cu conductor.
    Type: Grant
    Filed: February 7, 2002
    Date of Patent: February 10, 2004
    Assignee: Taiho Kogyo Co., Ltd.
    Inventors: Daisuke Yoshitome, Yasuhisa Tanaka
  • Patent number: 6687324
    Abstract: A metallic uranium article having a protective coating of a copper-tin alloy containing from 45 to 50% by weight of copper and from 55 to 50% by weight of tin, said alloy being firmly bonded to the metallic uranium.
    Type: Grant
    Filed: July 19, 1951
    Date of Patent: February 3, 2004
    Inventors: Ernest R. Boller, Lowell D. Eubank
  • Patent number: 6669077
    Abstract: A soldering method achieving a high-strength joint between a solder and an nickel/gold electroless plated surface is disclosed. The nickel/gold electroless plated layer is soldered using a solder including tin (Sn), silver (Ag), and copper (Cu). At a solder joint, a layer sturcture of nickel layer/intermetallic compound layer/solder layer is formed. The intermetallic compound layer is composed mainly of tin (Sn) and copper (Cu), and further including nickel (Ni). The intermetallic compound layer has cauliflower-shaped surfaces formed in a solder-layer's side thereof.
    Type: Grant
    Filed: September 1, 2000
    Date of Patent: December 30, 2003
    Assignee: NEC Corporation
    Inventors: Kazuyuki Kawashima, Yasunori Tanaka
  • Patent number: 6660226
    Abstract: A lead-free solder includes at least one selected from 0.01 to 1% by weight of Co, 0.01 to 0.2% by weight of, Fe, 0.01 to 0.2% by weight of Mn, 0.01 to 0.2% by weight of Cr, and 0.01 to 2% by weight of Pd; 0.5 to 2% by weight of Cu; and 90.5% by weight or more of Sn. This solder exhibits a satisfactory solderability in solder joints and shows a high resistance to electrode leaching upon soldering or when the resulting soldered article is left at high temperatures.
    Type: Grant
    Filed: August 7, 2000
    Date of Patent: December 9, 2003
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Hidekiyo Takaoka, Kiyotaka Maegawa
  • Publication number: 20030189086
    Abstract: One method of the present invention includes applying a paste-like fluxing agent to an aluminum body part; heating the fluxing agent to deoxidize the surface of the aluminum body part; applying a solder filler to the aluminum body part; and heating the solder filler to bond the solder filler to the aluminum body part. The melting point of the solder filler is at least 100 E C lower than the melting point of the aluminum body part. Another method includes forming a filler/flux mixture; applying the filler/flux mixture; and heating the filler/flux mixture to bond the solder filler to the aluminum body part. The disclosed solder fillers include tin-based alloys as follows: (1) 12-22% copper, 3-5% zinc and 75-85% tin; and (2) 3-5% copper, iron, cobalt, or nickel, 12-40% zinc and 55-85% tin and zinc-based solder filler alloys composed of 78-98% zinc and 2-22% aluminum.
    Type: Application
    Filed: April 9, 2002
    Publication date: October 9, 2003
    Applicant: Ford Motor Company
    Inventors: Nigel Frederick Clay, Tsung-Yu Pan, Alan Edward Gickler, Frederic Hilaire LePrevost
  • Publication number: 20030175146
    Abstract: A lead-free solder alloy consisting essentially of, by weight, 3.0% to 3.5% silver, greater than 1% to about 15% copper, the balance tin and incidental impurities, and having an effective melting range of about 215° C. to about 222° C. The solder alloy is noneutectic, and therefore characterized by solidus and liquidus temperatures, the former being in a range of about 215° C. to about 218° C., while the latter is about 290° C. or more. However, the melting mechanism exhibited by the alloy is such that the alloy is substantially all melted and does not exhibit a “mushy zone” above the effective melting range, enabling the alloy to behave similarly to the SnAgCu eutectic alloy.
    Type: Application
    Filed: March 15, 2002
    Publication date: September 18, 2003
    Inventors: Shing Yeh, Bradley H. Carter, Curtis W. Melcher
  • Publication number: 20030156969
    Abstract: A solder composition and associated method of formation. The solder composition comprises a substantially lead-free alloy that includes tin (Sn), silver (Ag), and copper. The tin has a weight percent concentration in the alloy of at least about 90%. The silver has a weight percent concentration X in the alloy. X is sufficiently small that formation of Ag3Sn plates is substantially suppressed when the alloy in a liquefied state is being solidified by being cooled to a lower temperature at which the solid Sn phase is nucleated. This lower temperature corresponds to an undercooling &dgr;T relative to the eutectic melting temperature of the alloy. Alternatively, X may be about 4.0% or less, wherein the liquefied alloy is cooled at a cooling rate that is high enough to substantially suppress Ag3Sn plate formation in the alloy. The copper has a weight percent concentration in the alloy not exceeding about 1.5%.
    Type: Application
    Filed: February 15, 2002
    Publication date: August 21, 2003
    Applicant: International Business Machines Corporation
    Inventors: Won K. Choi, Charles C. Goldsmith, Timothy A. Gosselin, Donald W. Henderson, Sung K. Kang, Karl J. Puttlitz, Da-Yuan Shih
  • Publication number: 20030091463
    Abstract: Wire burst faults at the time of solder attachment of conductors of an electronic component using insulation coated conductors having a core of copper or alloy containing alloy, is prevented.
    Type: Application
    Filed: October 25, 2002
    Publication date: May 15, 2003
    Inventors: Koichi Izumida, Yuki Takano, Hitoshi Abe, Toshiyuki Moribayashi, Koichi Hagio, Junichi Takenaka
  • Patent number: 6555052
    Abstract: An electronic equipment is capable of improving falling down shock resistance or impact resistance in an electronic equipment and of improving reliability of a solder joint in a semiconductor device die-bonded Si chip or the like to which thermal shock causing large deformation may act, bump mounting of BGA, CSP, WPP, flip-chip and so forth, a power module acting large stress and so forth. The electronic equipment has a circuit board and an electronic parts to be electrically connected to an electrode of the circuit board. The electrode of the circuit board and an electrode of the electronic part are connected by soldering using a lead free solder consisted of Cu: 0˜2.0 mass %, In: 0.1˜10 mass %, and Sn: remaining amount.
    Type: Grant
    Filed: March 7, 2001
    Date of Patent: April 29, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Tasao Soga, Hanae Shimokawa, Tetsuya Nakatsuka, Masato Nakamura, Yuji Fujita, Toshiharu Ishida, Masahide Okamoto, Koji Serizawa, Toshihiro Hachiya, Hideki Mukuno
  • Publication number: 20030044636
    Abstract: A free-space optical communication apparatus includes a storage unit which stores angle-setting information for the mirror for communicating with each of the plurality of other apparatuses, a mirror driving unit which drives the mirror to an angle corresponding to the stored angle-setting information, an optical detecting unit which, on one occasion for communicating with a specified communication apparatus among the plurality of other apparatuses, detects the incident state of an optical beam sent from the specified apparatus, and a control unit which, based on the detected incident state of the optical beam, determines angle-correcting information for correcting the stored angle-setting information for the specified apparatus, and which, on the next occasion for communicating with the specified apparatus, uses the mirror driving unit to drive the mirror to an angle corresponding to the angle-setting information corrected by the angle-correcting information.
    Type: Application
    Filed: August 23, 2002
    Publication date: March 6, 2003
    Applicant: Canon Kabushiki Kaisha
    Inventor: Tetsuo Sakanaka
  • Publication number: 20030021718
    Abstract: 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: Application
    Filed: June 20, 2002
    Publication date: January 30, 2003
    Inventors: Osamu Munekata, Yoshitaka Toyoda, Tsukasa Ohnishi, Minoru Ueshima
  • Publication number: 20030007885
    Abstract: Lead-free solder comprising Sn, Zn and 0.001 to 0.005 wt. % Ti. The lead-free solder does not contain toxic lead, and has sufficient bonding strength to oxide materials such as glass and ceramics.
    Type: Application
    Filed: June 13, 2002
    Publication date: January 9, 2003
    Inventors: Shinjiro Domi, Koichi Sakaguchi, Shigeki Nakagaki, Katsuaki Suganuma
  • Publication number: 20030007886
    Abstract: A substantially lead-free solder with enhanced properties comprises from 88.5% to 93.5% tin; from 3.5% to 4.5% silver; from 2.0% to 6.0% indium; and from 0.3% to 1.0% copper. The solder may also comprise up to 0.5% of an anti-oxidant or anti-skinning additive. A solder embodying the invention finds particular utility in wave-soldering processes where it may be used as a direct replacement for conventional tin/lead solder.
    Type: Application
    Filed: August 17, 2001
    Publication date: January 9, 2003
    Applicant: Quantum Chemical Technologies ( Singapore) Pte Ltd.
    Inventors: Chew Kai Hwa, Chih Pan Wei
  • Publication number: 20030003011
    Abstract: Lead-free solder balls having a good surface appearance with no appreciable surface defects such as seams and shrinkage cavities comprises an alloy having a composition consisting essentially of about 4.0% to about 6.0% by weight of Ag, about 1.0% to about 2.0% by weight of Cu, and a balance of Sn, and they have a diameter of from 0.05 mm to 1.0 mm. The solder balls can be produced by forming a molten alloy having the above-described composition into solidified balls having a diameter of from 0.05 mm to 1.0 mm using the surface tension of the molten alloy.
    Type: Application
    Filed: June 14, 2002
    Publication date: January 2, 2003
    Inventors: Rikiya Kato, Shinichi Nomoto, Hiroshi Okada
  • Publication number: 20020192106
    Abstract: A lead-free solder includes at least one selected from 0.01 to 1% by weight of Co, 0.01 to 0.2% by weight of Fe, 0.01 to 0.2% by weight of Mn, 0.01 to 0.2% by weight of Cr, and 0.01 to 2% by weight of Pd; 0.5 to 2% by weight of Cu; and 90.5% by weight or more of Sn. This solder exhibits a satisfactory solderabiliy in solder joints and shows a high resistance to electrode teaching upon soldering or when the resulting soldered article is left at high temperatures.
    Type: Application
    Filed: June 25, 2002
    Publication date: December 19, 2002
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Hidekiyo Takaoka, Kiyotaka Maegawa
  • Publication number: 20020159913
    Abstract: A Pb-free solder is provided, which has a satisfactory low melting point and suppresses effectively the “copper leaching” phenomenon. The solder is difficult to be oxidized and has a high wettability. The solder consists essentially of (a) 1.0 to 4.0 wt % of Ag, (b) 0.4 to 1.3 wt % of Cu; (c) at least one of 0.02 to 0.06 wt % (or 0.02 to 0.04 wt %) of Ni and 0.02 to 0.06 wt % (or 0.02 to 0.05 wt %) of Fe; and (d) a balance of Sn. The solder has a copper dissolution rate of 0.20 or 0.15 &mgr;m or less. Preferably, the solder has a liquidus temperature of 240° C. or lower, in which a satisfactory low melting point is ensured. More preferably, the solder has a liquidus temperature of 230° C. or lower. It is preferred that the solder has a viscosity of 2.5 cP or lower.
    Type: Application
    Filed: April 23, 2002
    Publication date: October 31, 2002
    Inventors: Toshihide Ito, Shiro Hara
  • Publication number: 20020150787
    Abstract: A lead-free solder, which contains from 1.0 to 3.5% of Ag, from 0.1 to 0.7% of Cu, and from 0.1 to 2.0% of In, the balance consisting of unavoidable impurities and Sn, is appropriate for ball-grid array (BGA). The solute Cu suppresses growth of intermetallic compound formed at the interface between the bulk of solder and a Ni or Cu conductor.
    Type: Application
    Filed: February 7, 2002
    Publication date: October 17, 2002
    Applicant: Taiho Kogyo Co., Ltd.
    Inventors: Daisuke Yoshitome, Yasuhisa Tanaka
  • Publication number: 20020131887
    Abstract: A lead-free solder includes at least one selected from 0.01 to 1% by weight of Co, 0.01 to 0.2% by weight of Fe, 0.01 to 0.2% by weight of Mn, 0.01 to 0.2% by weight of Cr, and 0.01 to 2% by weight of Pd; 0.5 to 2% by weight of Cu; and 90.5% by weight or more of Sn. This solder exhibits a satisfactory solderability in solder joints and shows a high resistance to electrode leaching upon soldering or when the resulting soldered article is left at high temperatures.
    Type: Application
    Filed: March 5, 2002
    Publication date: September 19, 2002
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Hidekiyo Takaoka, Kiyotaka Maegawa
  • Publication number: 20020117539
    Abstract: A solder consists essentially of 1.0% to 4.0% of Ag by mass, 0.2% to 1.3% of Cu by mass, 0.02% to 0.06% of Co by mass, and the remaining of Sn and inevitable impurities.
    Type: Application
    Filed: December 11, 2001
    Publication date: August 29, 2002
    Applicant: NEC CORPORATION
    Inventors: Toshihide Ito, Shiro Hara
  • Patent number: 6440360
    Abstract: The present invention proposes Pb-free soldering alloy which does not contain Pb to prevent the environment from being contaminated by Pb when the soldered product is put on a wasteyard and to enhance the mechanical strength at the soldered joint by the soldering alloy. The Pb-free soldering alloy is characterized in that it contains Cu in 0.05 to 2.0 wt. %, Ni in 0.001 to 2.0 wt. % and Sn in the balance.
    Type: Grant
    Filed: March 2, 2001
    Date of Patent: August 27, 2002
    Assignee: Tokyo First Trading Company
    Inventors: Tadashi Sawamura, Hisashi Komiya
  • Patent number: 6371361
    Abstract: The present invention relates to a soldering alloy composed mainly of Sn and free from lead, a toxic substance. Adding a small quantity of Ag to the soldering alloy can make the alloy structure fine, minimize structural changes of the alloy and increase its thermal fatigue resistance. Adding a small quantity of Bi to the soldering alloy lowers the melting point and improves the alloy's wettability. Further, adding a small quantity of Cu restrains the growth of intermetallic compounds in the bonding interface between a copper land and the solder. Furthermore, addition of a small quantity of In improves the elongation property and thermal fatigue resistance of the alloy.
    Type: Grant
    Filed: February 19, 1999
    Date of Patent: April 16, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Atsushi Yamaguchi, Tetsuo Fukushima
  • Patent number: 6319461
    Abstract: A lead-free solder alloy substantially contains Sn and Ti, and has a temperature of a liquidus line of not greater than 400° C. The lead-free solder alloy contains no toxic lead and has sufficient bonding strength to oxide materials such as glass and ceramics.
    Type: Grant
    Filed: January 30, 2001
    Date of Patent: November 20, 2001
    Assignee: Nippon Sheet Glass Co., Ltd.
    Inventors: Shinjiro Domi, Koichi Sakaguchi, Shigeki Nakagaki, Katsuaki Suganuma
  • Patent number: 6313412
    Abstract: A method of assembling a substrate and an electrical or electronic component, the component having electrically conductive leads with surfaces of an alloy from the list consisting of tin, nickel, tin copper, tin silver, nickel palladium, gold palladium, and silver palladium, and the leads being soldered to copper-based terminals of the substrate by a solder alloy, the solder alloy comprising, by weight, 99.3% tin and 0.7% copper. The soldering takes place in a chamber having a nitrogen inert atmosphere. Lead solder is thus avoided.
    Type: Grant
    Filed: August 6, 1998
    Date of Patent: November 6, 2001
    Assignee: Nortel Networks Limited
    Inventors: William P. Trumble, Murray W. Hamilton, David Bilton
  • Publication number: 20010025875
    Abstract: Disclosed are a solder and a solder paste used for soldering an electronic part to a circuit board. This solder comprises 2.0 to 3.5 wt % of Ag, 5 to 18 wt % of Bi and Sn for the rest. Alternatively, it further contains at least one element selected from the group consisting of 0.1 to 1.5 wt % of In, 0.1 to 0.7 wt % of Cu and 0.1 to 10 wt % of Zn.
    Type: Application
    Filed: May 16, 2001
    Publication date: October 4, 2001
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Atsushi Yamaguchi, Tetsuo Fukushima, Kenichiro Suetsugu, Akio Furusawa
  • Patent number: 6296722
    Abstract: A lead-free solder characterized as comprising 0.1 to 2 wt % of Cu, 0.002 to 1 wt % of Ni with the residue being Sn. The solder preferably contains Cu in an amount of 0.3 to 0.7 wt %, and more preferably it contains Cu in an amount of 0.3 to 0.7 wt % and Ni in an amount of 0.04 to 0.1 wt %. The solder can be prepared by adding Ni to a molten mother alloy of Sn—Cu, or by adding Cu to a molten mother alloy of Sn—Ni. A lead-free solder which further comprises 0.001 to 1 wt % of Ga is also disclosed. The lead-free solder can form a solder joint having a high strength and stability comparable to those of a conventional Sn—Pb eutectic solder.
    Type: Grant
    Filed: June 28, 2000
    Date of Patent: October 2, 2001
    Assignee: Nihon Superior Sha Co., Ltd.
    Inventor: Tetsuro Nishimura
  • Patent number: 6231691
    Abstract: A Sn—Ag—Cu eutectic alloy is modified with one or more low level and low cost alloy additions to enhance high temperature microstructural stability and thermal-mechanical fatigue strength without decreasing solderability. Purposeful fourth or fifth element additions in the collective amount not exceeding about 1 weight % (wt. %) are added to Sn—Ag—Cu eutectic solder alloy based on the ternary eutectic Sn—4.7%Ag—1.7%Cu (wt. %) and are selected from the group consisting essentially of Ni, Fe, and like-acting elements as modifiers of the intermetallic interface between the solder and substrate to improve high temperature solder joint microstructural stability and solder joint thermal-mechanical fatigue strength.
    Type: Grant
    Filed: February 10, 1997
    Date of Patent: May 15, 2001
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: Iver E. Anderson, Robert L. Terpstra
  • Patent number: 6229248
    Abstract: The invention provides a solder alloy of Sn, Sb, Ag and Cu, wherein the Sb is about 1.0-3.0 wt %; the Ag is about 1.0 wt % or more and about 2.0 wt % or less; the Cu is about 1.0 wt % or less; and the remainder is Sn. The solder alloy has a comparatively low Young's modulus and sufficient tensile characteristics. Therefore, it resists peeling from the bonded electrode, etc., even though a heat stress is added. Also, a solder which has an excellent solderbility to metal phases such as Cu and Ni can be provided. Therefore, a solder alloy excellent in thermal shock resistance can be provided. The solder alloy may be used for soldering the inside of an electronic component.
    Type: Grant
    Filed: February 26, 1999
    Date of Patent: May 8, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Shigemasa Kusabiraki, Manabu Sumita
  • Patent number: 6228322
    Abstract: A lead-free solder composition having superior mechanical strength is produced by adding a rare earth element to a Sn—Ag alloy or a Sn—Ag—Bi—Cu alloy. The rare earth element is Sm, Gd, or a mixture of these elements with other rare earth elements.
    Type: Grant
    Filed: September 17, 1999
    Date of Patent: May 8, 2001
    Assignee: Sony Corporation
    Inventors: Naoko Takeda, Kazutaka Habu, Kazushi Yamauchi
  • Publication number: 20010000321
    Abstract: A lead-free solder composition having superior mechanical strength is produced by adding a rare earth element to a Sn-Ag alloy or a Sn-Ag-Bi-Cu alloy.
    Type: Application
    Filed: November 29, 2000
    Publication date: April 19, 2001
    Inventors: Naoko Takeda, Kazutaka Habu, Kazushi Yamauchi
  • Patent number: 6204490
    Abstract: Electronic components are bonded to an electronic circuit board with a lead-free solder. The bonded structure is cooled from a temperature close to the liquids temperature of the solder to a temperature close to the solids temperature of the solder at a first cooling rate of about 10 to 20° C./second, followed by cooling the bonded structure to a temperature lower than the solids temperature of the solder at a second cooling rate of about 0.1 to less than 5° C./second.
    Type: Grant
    Filed: June 1, 1999
    Date of Patent: March 20, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Tasao Soga, Toshiharu Ishida, Tetsuya Nakatsuka, Hanae Shimokawa, Koji Serizawa, Yasuo Amano, Suguru Sakaguchi, Hiroshi Yamaguchi
  • Patent number: 6187114
    Abstract: This invention provides a lead-free high temperature solder material comprising 0.005-3.0 wt % of palladium (Pd) and 97.0-99.995 wt % of tin (Sn) whose liquidus temperature is 200-350° C. The solder material is environmentally-friendly, improved in thermal fatigue property, and it can improve the reliability of electronic apparatuses. A predetermined amount of Sn material and Pd is mixed, vacuum-melted and cast to prepare an ingot. The ingot is rolled to be a tape that is later pressed to obtain a solder pellet. In a preferable composition, at least 95 wt % of Sn and 0.005-3.0 wt 5 of Pd are contained, and 0.1-5.0 wt % of metallic (e.g. Cu, Ni) or alloy particles are added. The average particle diameter is about 40 &mgr;m. A substrate and an IC chip (electronic element) are die-bonded substantially in parallel by a solder material provided between an Ni plating on the lower side of an IC chip (semiconductor) and an Ni plating on a die.
    Type: Grant
    Filed: October 14, 1997
    Date of Patent: February 13, 2001
    Assignees: Matsushita Electric Industrial Co. Ltd., Tanaka Denshi Kogyo K.K.
    Inventors: Toshinori Ogashiwa, Takatoshi Arikawa, Masami Yokozawa, Kazuhiro Aoi, Yoshiharu Sawada
  • Patent number: 6180055
    Abstract: A lead-free solder which is comprised of three elements Sn-Cu-Ni. Cu and Ni are 0.1-2 wt % and 0.002-1 wt % respectively. Preferable weight percentage of Cu and Ni are 0.3 to 0.7 percent and 0.04 to 0.1 percent respectively. Both methods of additive Ni to a base alloy of Sn—Cu and additive Cu to a base alloy of Sn—Ni are applicable.
    Type: Grant
    Filed: November 24, 1999
    Date of Patent: January 30, 2001
    Assignee: Nihon Superior Sha Co., Ltd.
    Inventor: Nishimura Tetsuro
  • Patent number: 6179935
    Abstract: A solder alloy which is lead free, consists essentially of, in weight %: Sn; 0<Ag≦4.0; 0<Cu≦2.0; 0<Ni≦1.0; and 0<Ge≦1.0, wherein addition of Ni and Ge to the solder alloy enhances wettability and tensile strength, and prevents formation of an oxide film. Additionally, a solder alloy which is lead free, consists essentially of, in weight %: Sn; 0<Sb≦3.5; 0≦Ag ≦4.0; 0<Ge≦1.0; and at least one first additive selected from the group consisting of (a) 0<Ni≦1.0 and (b) a combination of 0<Ni≦1.0 and 0<Cu≦1.0; wherein addition of Ni and Ge to the solder alloy enhances wettability and tensile strength, and prevents formation of an oxide film.
    Type: Grant
    Filed: April 14, 1998
    Date of Patent: January 30, 2001
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Mitsuo Yamashita, Shinji Tada, Kunio Shiokawa
  • Patent number: 6176947
    Abstract: Disclosed is a high strength, high fatigue resistance, and high wetting lead-free solder alloy comprising effective amounts of tin, copper, silver, bismuth, indium, and antimony and having a melting temperature between 175-215° C.
    Type: Grant
    Filed: October 12, 1999
    Date of Patent: January 23, 2001
    Assignee: H-Technologies Group, Incorporated
    Inventors: Jennie S. Hwang, Zhenfeng Guo
  • Patent number: 6158350
    Abstract: The instant invention is a lightweight enhanced velocity bullet consisting of a hollow cylindrically shaped metal jacket component made of brass, the body of which is filled nearly to capacity with a malleable tin-copper-silver alloy material and with the body having a flattened posterior end and with there being a second end anterior to the body which said second end is hollow within, devoid of any alloy material and tapering symmetrically to a blunt point.
    Type: Grant
    Filed: May 28, 1999
    Date of Patent: December 12, 2000
    Inventor: Valentino Pulcini
  • Patent number: 6139979
    Abstract: A lead-free solder contains nickel, silver and tin. A soldered article is a workpiece containing a transition metal conductor capable of readily diffusing into melted tin; and the lead-free solder; wherein the lead-free solder is applied and bonded to the workpiece so as to be electrically and mechanically bonded to the transition metal conductor. The lead-free solder and soldered article barely cause electrode erosion during soldering or during aging after soldering, and have high tensile strength and thermal impact resistance.
    Type: Grant
    Filed: April 9, 1999
    Date of Patent: October 31, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Hidekiyo Takaoka, Kiyotaka Maegawa
  • Patent number: 6096245
    Abstract: Provided are a conductive resin composition having little negative impact on the environment, a resin molding which includes conductive parts of the conductive resin composition and insulating parts, and their methods of production. The production costs for the resin molding are low. The conductive resin composition is formed by kneading a thermoplastic or thermosetting resin with a low melting point alloy, wherein the low melting point alloy is moldable with the resin and consists essentially of tin and is free of lead. An insulating body is formed through primary molding of a thermoplastic or thermosetting resin, and is integrated with conductive parts of the conductive resin composition through secondary molding; or alternatively, conductive parts are formed through primary molding of the conductive resin composition and an insulating body is formed while being integrated with the conductive parts through secondary molding.
    Type: Grant
    Filed: August 7, 1998
    Date of Patent: August 1, 2000
    Assignee: Aisin Seiki Kabushiki Kaisha
    Inventors: Tsuyoshi Tanigaki, Shogo Izawa, Akikazu Matsumoto, Tadahiko Kohama