Senju Metal Industry Co., Ltd.

Mitsubishi Denki Kabushiki Kaisha

Senju Metal Indsutry Co., Ltd.

Ken Tachibana

Shunsaku Yoshikawa

Hikaru Nomura

Yoshie Yamanaka

Tsukasa Ohnishi

Takahiro Hattori

Ikuo Musa

Naoko Izumita

Masayuki A Suzuki

Takashi Saito

Shiro Yonezawa

Takahiro Yokoyama

Kyu-Oh Lee

Yoshie Tachibana

Masato Shimamura

Rei Fujimaki

Shogo Nakashima

Naoko Hirai

Yuki Iijima

Takayuki Hori

Yuya Nagasawa

Masato Oonishi

A solder alloy that contains 0.005 mass % or more and 0.1 mass % or less of Mn, 0.001 mass % or more and 0.1 mass % or less of Ge, and a balance of Sn. A plurality of Ge oxides is distributed on an outermost surface side of an oxide film including Sn oxide, Mn oxide and Ge oxide by adding 0.005 mass % or more and 0.1 mass % or less of Mn, 0.001 mass % or more and 0.1 mass % or less of Ge to the solder alloy having a principal ingredient of Sn, so that it is possible to obtain the discolor-inhibiting effect even under the high-temperature and high-humidity environment.

Solder alloy, solder ball, chip solder, solder paste and solder joint

Provided is a solder alloy, a solder ball, a chip solder, a solder paste and a solder joint in which discoloration is suppressed and a growth of an oxide film is suppressed under a high temperature and high humidity environment. The solder alloy contains 0.005% by mass or more and 0.1% by mass or less of Mn, 0.001% by mass or more and 0.1% by mass or less of Ge and more than 0% by mass and 4% by mass or less of Ag, and a principal ingredient of remainder is Sn.

Solder alloy, solder ball, chip solder, solder paste, and solder joint

A solder alloy has an alloy composition consisting of, in mass %: Bi: 0.1% or more and less than 2.0%, Cu: 0.1 to 1.0%, Ni: 0.01 to 0.20%, Ge: 0.006 to 0.09%, and Co: 0.003% or more and less than 0.05%, and optionally Fe: 0.005 to 0.015% and P: 0.1% or less, with the balance being Sn.

Solder alloy, solder ball, and solder joint

Lead-free solder is characterized in that the lead-free solder contains Ag of 1.2 mass % through 4.5 mass %, Cu of 0.25 mass % through 0.75 mass %, Bi of 1 mass % through 5.8 mass %, Ni of 0.01 mass % through 0.15 mass % and Sn as the remainder. These addition amounts allow to be further improved the common solder properties such as wettability, shear strength properties and the like, in addition to the thermal fatigue resistance.

Lead-free solder, lead-free solder ball, solder joint using the lead-free solder and semiconductor circuit having the solder joint

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.

Lead-free solder alloy

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&#xb0; C. and can be used not only for CPUs but also for power semiconductors.

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 &#x2212;40&#xb0; C. to high temperatures of 125&#xb0; 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.

Lead-free solder alloy and in-vehicle electronic circuit

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 %.

Lead-free solder ball

Provided is a process for mounting a BGA (Ball Grid Array) or CSP (Chip Size Package) on a printed circuit board. The process includes melting and fusing together solder paste and a solder ball. The solder ball has a solder composition that includes 0.5-1.1 mass % of Ag, 0.7-0.8 mass % of Cu, 0.05-0.08 mass % of Ni, and a remainder of Sn. In the process, the solder ball is placed on an electrode of the BGA or CSP substrate and the solder paste is applied onto an opposing electrode of the printed circuit board.

A lead-free solder ball for electrodes of a BGA or CSP comprising 0.5-1.1 mass % of Ag, 0.7-0.8 mass % of Cu, 0.05-0.08 mass % of Ni, and a remainder of Sn. Even when a printed circuit board to which the solder ball is bonded has Cu electrodes or Au-plated or Au/Pd-plated Ni electrodes, the solder ball has good resistance to drop impacts. The composition may further contain 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 %.

Even if the strength of a solder composition close to a SnBi eutectic composition was improved, it was brittle, so when it was used for small electronic devices such as mobile phones or notebook computers, the resistance to drop impacts when the small electronic equipment was dropped was low. Therefore, interface peeling often took place between the soldered surface and a printed circuit board, resulting in the devices being destroyed. As disclosed, when soldering using a solder paste containing a SnBi-based low-temperature solder, at least one type of solder composition selected from a Sn&#x2014;Ag, a Sn&#x2014;Cu, and a Sn&#x2014;Ag&#x2014;Cu solder composition is diffused into the solder paste by simultaneously supplying at least one type of preform selected from a Sn&#x2014;Ag, a Sn&#x2014;Cu, and a Sn&#x2014;Ag&#x2014;Cu solder composition, whereby resistance to drop impacts is improved.

Soldering method using a low-temperature solder paste

A control apparatus of an internal combustion engine, for preventing a throttle valve from freezing when the internal combustion engine is stopped. A control unit is constructed to receive power from a battery ancillary to an internal combustion engine when the internal combustion engine is stopped and perform a probability determination of whether or not the probability of a throttle valve freezing is high. When this probability is high, the control unit controls the throttle valve to execute a freeze protection operation, including a valve opening and closing operation of the throttle valve, before the throttle valve freezes. The probability determination is carried out using environmental temperature detecting means, engine temperature detecting means, date/time information outputting means, location information detecting means, and a drive level of an exhaust recirculating device.

Control apparatus of internal combustion engine

A memory rewriting apparatus can rewrite control programs for a vehicle mounted ECU through communications reliably and easily. A transmission and reception circuit communicates with a data communications device that sends program data. An ID check circuit checks based on an ID check code attached to the data whether a subject vehicle on which the apparatus is installed is a vehicle to be rewritten. A communications condition determination device determines whether the communications condition is suitable for communications. A control part (MPU) controls writing program data into a memory of the vehicle mounted ECU. The control part notifies the non-completion of rewriting to the data communications device when determined, before and during data rewriting, that the communications condition is unsuitable, and it also notifies the completion of rewriting to the data communications device after the rewriting of the data has been completed, when determined that the communications condition is suitable.

Apparatus for rewriting a memory in a vehicle mounted ECU through communications

A start control apparatus includes a starter, a number-of-revolutions detection unit of an internal combustion engine, a crank angle sensor, a cam sensor, and a control unit for controlling cylinder ignition based on a crank angle signal and a cam signal. The control unit has a start determination unit for determining whether starting the engine is to be continued or stopped based on the crank angle and fluctuation in the number of revolutions when the starter being switched from on to off is detected, and controls continuing or stopping ignition control in accordance with the determination of the start determination unit.

Start control apparatus of internal combustion engine

In an internal combustion engine of a cylinder injection type, a fuel injection control system for controlling fuel injection/combustion effected during an expansion stroke or an exhaust stroke of the engine in order to heat a catalyst to a light-on temperature as soon as possible in an engine starting phase while protecting the catalyst against degradation/dissolution and ensuring purification of exhaust gas at an earlier stage regardless of changes in the ambient temperature and the state of a motor vehicle prevailing when the engine is restarted from the cold state or when the engine is restarted after having been stopped in the warmed-up state and additionally proper temperature rise as well as prevention of discharge of unburnt gas. The system includes fuel injection valves (47 to 50) capable of injecting fuel under high pressure directly into combustion chambers (24, 26, 28, 30) of an engine (10), an engine start detecting means for detecting starting of the engine (10), a temperature detecting means (55) for detecting temperature (T.sub.W) of the engine (10), and an engine low-temperature state detecting means (22) for detecting whether or not the engine is at a low temperature by comparing a detected value (T.sub.W) derived from output of the temperature detecting means (55) with a predetermined value stored previously.

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Tokyo, Japan

Ken Tachibana