Senju Metal Industry Co., Ltd.

Denso Corporation

Nitta Corporation

Nikku Industry Co., Ltd.

Kaichi Tsuruta

Manabu Muraoka

Takeo Saitoh

Takeo Kuramoto

Takashi Hagiwara

Naohiko Hirano

Yoshitsugu Sakamoto

Hiroki Oshima

Naoto Kameda

Takashi Ishii

Katsuji Nakamura

Hiroyoshi Kawasaki

Hiroyuki Yamasaki

Osamu Munekata

Akira Tanahashi

Kota Kikuchi

Shigeaki Watarai

Shigeyuki Sekine

Takashi Obayashi

Yuji Ozaki

Hidenori Takagi

Yutaka Ohori

Satoshi Soga

Isamu Sato

Minoru Ueshima

Tomomi Okumura

Takahiro Roppongi

Daisuke Soma

Yuji Kawamata

Masato Shiratori

Hiroshi Kawanago

Tomohisa Kawanago

Yoko Kurasawa

Shigeki Kondo

Takahiro Nishizaki

Atsushi Ikeda

Motohiro Onitsuka

Shinichiro Kawahara

Masato Tsuchiya

Kunihito Takaura

Koji Yamashita

Osamu Kawakami

Toshihisa Kugi

Hiroshi Takahashi

Yuri Nakamura

Takeo Saito

Hiroshi Kawanakago

Takeo Saitou

In a layered bonding material, a coefficient of linear expansion of a base materialis 5.5 to 15.5 ppm/K and a first surface and a second surface of the base materialare coated with pieces of lead-free solderand

Layered bonding material, semiconductor package, and power module

A solder ball according to the present invention contains 0.2 to 2.2% by mass of Zn, and a balance of Sn, and has a spherical diameter of 0.1 to 120 &#x3bc;m and a yellowness (b*) in an L*a*b* color system of 2.70 or more and 9.52 or less. An oxide film is formed by performing aging treatment. By producing a solder ball having a yellowness of 2.70 or more and 9.52 or less, it is possible to suppress the growth of a CuSn layer and/or a Cu&#x2014;Zn(&#x2014;Sn) layer during joining.

Solder ball, solder joint, and joining method

A solder ball includes 0.1% by mass or more and 10% by mass or less of In and a remainder of Sn. The ball has a yellowness (b*) in an L*a*b* color system of 2.8 or more and 15.0 or less and a lightness (L*) of 60 or more and 100 or less. The ball further includes at least one element selected from a group of 0% by mass or more and 4% by mass or less of Ag, 0% by mass or more and 1.0% by mass or less of Cu, 0% to 3% by mass in total of Bi and/or Sb, and 0% to 0.1% by mass in total of an element selected from a group of Ni, Co, Fe, Ge, and P, excluding a solder ball including 3% by mass of Ag, 0.5% by mass of Cu, 0.2% by mass of In and a remainder of Sn.

A solder-ball-supplying method, a solder-ball-supplying device and a solder-bump-forming method, which are flux-less and capable of being also applied to electrodes having a fine pitch. A substrate on which a resist with openings is positioned on electrode(s), which has a diameter of 10 through 30 &#x3bc;m, of the substrate is prepared. Next, plural solder balls SBL each having a grain diameter of 1 through 10 &#x3bc;m are shaken down to the opening(s) of the resist from a hopper and filled therein. Next, by sliding and moving a squeegee on an upper surface of the resist along X-Y direction, the solder balls SBL shaken down to the resist other than the openings are scrapped and removed and the solder balls SBL in the openings and around them are pushed into the openings by the squeegee.

Solder ball supplying method, solder ball supplying device, and solder bump forming method

Provided herein is a solder material that includes a spherical core that provides space between a joint object and another object to be joined to the joint object and a solder coated layer that has a melting point at which a core layer of the core is not melted. The solder coated layer includes Sn as a main ingredient and 0 to 2 mass % of Ag, and coats the core. The solder coated layer has an average grain diameter of crystal grains of 3 &#x3bc;m or less, and the solder material has a spherical diameter of 1 to 230 &#x3bc;m and a sphericity of 0.95 or more.

Joining member, solder material, solder paste, formed solder, flux coated material, and solder joint

A flux applying device for applying flux to a surface of solder, wherein the flux applying device includes: a dipping means that applies the flux to the surface of the solder by dipping the solder into the flux; a load applying means that applies a predetermined load to the solder, the load applying means being provided at a upstream side of the dipping means; a constant speed conveying means that conveys the solder at a predetermined speed with being under load by the load applying means; a drying means that dries the solder to which the flux is applied; a cooling means that cools the dried solder; a conveying speed measurement means that measures a conveying speed of the solder; and a control means that controls the conveying speed of the solder.

Flux applying device

A flux for a resin flux cored solder contains 30% or more by mass but 80% or less by mass rosin ester and 5% or more by mass but 15% or less by mass activator. The total content ratio of base materials including the rosin ester is preferably equal to or more than 85% by mass but equal to or less than 95% by mass.

Flux for resin flux cored solder, flux for flux coated solder, resin flux cored solder and flux coated solder

In the flux applying device, a control portion controls conveying rollers or the like so that thickness of flux applied to solder is controlled. The winding roller rotates so that the solder is conveyed at the conveying speed. The drawing-out roller applies any load (back tension) to the solder backward along the conveying direction of the solder when drawing out the solder. The solder is conveyed at the predetermined speed and dipped into the flux tank containing flux. The solder is pulled up from the flux tank at the conveying speed vertically. By pulling up the solder from the flux tank at the constant conveying speed vertically, the interfacial tension acts on the solderand the flux, so that the flux having a uniform thickness according to the conveying speed remains on the surface and back surface of the solder.

Liquid coating device

An electrode for an energy storage device including a Zn layer or Zn alloy layer, a Ni layer, and a Sn layer or Sn alloy layer formed by plating on a connecting terminal part of a positive electrode composed of Al so that the resistance value at the contacting point is reduced and the voltage of the energy storage device can be effectively supplied without any drop. Accordingly, this electrode can be soldered to a Cu negative electrode, which is composed of metal that is different species from Al, through a Sn layer or a Sn alloy layer so that jointing strength of the Al positive electrode and the Cu negative electrode can be enhanced. The contacting area is increased in comparison with the conventional jointing by spot-welding or conventional fastening by a bolt so that the resistance value at the contacting point is reduced.

Method of manufacturing an electrode for an energy storage device

Provided is a solder transfer sheet which is capable of increasing the amount of solder to be transferred without the occurrence of bridging. A solder transfer sheetA includes a base material, an adhesive layerformed on the surface of the base material, a solder powder-containing adhesive layerformed on the surface of the adhesive layer, and a solder powder layerformed on the surface of the solder powder-containing adhesive layer. In the solder powder layer, particles of solder powderare arranged in a one-layer sheet form. In the solder powder-containing adhesive layer, solder powderand an adhesive componentare mixed so as to have such a thickness that two or more layers of the solder powderare stacked.

Solder transfer sheet, solder bump, and solder precoating method using solder transfer sheet

A mixed mother alloy is prepared from a solder mixture comprising a pyrolyzable flux and high melting point metal particles, the mixed mother alloy is charged into a large amount of molten solder and stirred, and a billet is prepared. The billet can then be extruded, rolled, and punched to form a pellet or a washer, for example.

Solder preform and a process for its manufacture

Problem Precoating methods for previously adhering solder to areas to be soldered of a workpiece for an electronic part such as a printed circuit board, a chip part, or a wafer include the plating method, the hot leveling method, the solder paste method, the solder ball method, and the like. In these conventional precoating methods, solder did not uniformly adhere to areas to be soldered, solder did not completely adhere, and much equipment and time were required. The present invention provides a method which can perform precoating with uniform application and without the occurrence of defects using simple equipment and a workpiece to which solder is uniformly adhered. Means for Solving the Problem In the present invention, an excess amount of solder powder is dispersed atop an adhesive applied to a substrate, and then excess solder powder which is not adhered to the adhesive is removed. The surface on with solder powder is dispersed is then stacked on a workpiece to which flux is applied with the application of pressure, heating is then performed, and solder is adhered only to areas to be soldered.

Solder precoating method and workpiece for electronic equipment

Zn layeror Zn alloy layer, Ni layer, and Sn layeror Sn alloy layer are formed on a connecting terminal partof a positive electrode composed of Al by plating. Accordingly, this can solder Cu negative electrode, which is composed of metal that is different species from Al, through Sn layeror Sn alloy layer so that jointing strength of the Al positive electrode and the Cu negative electrode can be enhanced. Further, since the contacting area is increased in comparison with the conventional jointing by the spot-welding or the conventional fastening by a bolt so that the resistance value at the contacting point is reduced, the voltage drop of the energy storage device by contact resistance can be reduced.

A solder paste using a Sn&#x2014;Ag base, Sn&#x2014;Cu base, or similar alloy powder has a high melting point, so it causes thermal damage to electronic devices. Sn&#x2014;Ag&#x2014;In base lead-free solder alloys having a low melting temperature have been studied, but they are difficult to use because they cause much occurrence of chips standing up during reflow. The present invention forms a solder paste by separating a Sn&#x2014;Ag&#x2014;In base lead-free solder into first and second solder alloy powders for which the difference in their peak temperatures measured by differential thermal analysis is at least 10&#xb0; C. and blends the mixed powders with a flux.

Solder paste

A method of forming solder bumps on electrodes of a circuit board without producing bridging using a solder transfer sheet which does not require alignment includes superposing a circuit board and a solder transfer sheet having a solder layer adhered to at least one side of a supporting substrate, performing heating under pressure to a temperature lower than the solidus temperature of the solder to selectively perform solid phase diffusion bonding of the solder layer to electrodes, and peeling the transfer sheet from the circuit board. The solder layer is in the form of a continuous solder coating or in the form of a monoparticle layer of solder particles which are adhered to the supporting substrate by an adhesive layer.

Solder bump formation on a circuit board using a transfer sheet

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Tochigi, Japan

Kaichi Tsuruta