JPH01230213A - Electronic part - Google Patents

Electronic part

Info

Publication number
JPH01230213A
JPH01230213A JP63055712A JP5571288A JPH01230213A JP H01230213 A JPH01230213 A JP H01230213A JP 63055712 A JP63055712 A JP 63055712A JP 5571288 A JP5571288 A JP 5571288A JP H01230213 A JPH01230213 A JP H01230213A
Authority
JP
Japan
Prior art keywords
solder
soldering
copper powder
compound
lead
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP63055712A
Other languages
Japanese (ja)
Inventor
Shigeki Saito
斎藤 茂樹
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Murata Manufacturing Co Ltd
Original Assignee
Murata Manufacturing Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Murata Manufacturing Co Ltd filed Critical Murata Manufacturing Co Ltd
Priority to JP63055712A priority Critical patent/JPH01230213A/en
Publication of JPH01230213A publication Critical patent/JPH01230213A/en
Pending legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00Apparatus or processes for manufacturing printed circuits
    • H05K3/30Assembling printed circuits with electric components, e.g. with resistor
    • H05K3/32Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
    • H05K3/34Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
    • H05K3/3457Solder materials or compositions; Methods of application thereof

Abstract

PURPOSE:To prevent short circuits due to the falling of lead terminals and the outflow of solder, by heating solder cream in which copper powder is added, performing soldering during this time, and transforming the composition at a part of the solder. CONSTITUTION:Solder cream 2 is formed with powder 3 incorporating tin Sn and lead Pb and paste 4 incorporating flux and solvent. An adequate amount of copper powder 1 is added. The solder cream 2 is applied between a terminal attaching electrode 5 and a lead terminal in an electronic part. The electronic part is heated by passing the electronic part in a heating furnace for reflow. Thus, the solder cream 2 is fused to effect soldering. At this time, the copper powder 1 reacts with surrounding tin by heat treatment, and a compound 6 between Cu-Sn metals is formed. The melting temperature of the compound 6 is higher than the melting temperature of a base material 7. The fused solder cream 2 at the part of the base material 7 is supported with the part of the compound 6 that is not fused. Therefore, short circuits due to the falling of the lead terminal and the flowing solder can be prevented at the part of the compound 6.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は電子部品に関し、さらに詳しくは、リード端子
をはんだ付けされたコンデンサ、抵抗体、圧電共振子そ
の他の電子部品に関する。
DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to electronic components, and more particularly to capacitors, resistors, piezoelectric resonators, and other electronic components having soldered lead terminals.

〔背景技術〕[Background technology]

リード端子の付いた電子部品にあっては、2回以上のは
んだ付は工程が行われるのが一般的である。すなわち、
その電子部品の製造時におけるエレメントの端子取付用
電極とリード端子とのはんだ付けの工程(以下、第一工
程という、)と、リード端子取付は後の電子部品をプリ
ント基板等に実装する際におけるリード端子と基板との
はんだ付けの工程(以下、第二工程という、)とである
For electronic components with lead terminals, the soldering process is generally performed two or more times. That is,
The soldering process (hereinafter referred to as the first process) between the terminal mounting electrode of the element and the lead terminal during the manufacture of the electronic component, and the soldering process of the lead terminal attachment are performed later when the electronic component is mounted on a printed circuit board, etc. This is the process of soldering the lead terminals and the board (hereinafter referred to as the second process).

この場合、第一工程において用いられるはんだと第二工
程において用いられるはんだとが略同じ融点温度をもつ
ものであると、第二工程におけるはんだ付は時にリード
端子とエレメントの端子取付用電極との間のはんだ付は
部分が加熱された時、第一工程のはんだが再溶融して流
れ出し、リード端子がエレメントから脱落したり、流れ
たはんだによってショートが発生するという問題がある
。このため、従来にあっては(特に、熱容量の小さな電
子部品では)、第一工程のはんだ材料として第二工程の
はんだ材料(例えば、5n63−Pb37のはんだでは
融点温度は183℃程度で、はんだ付は温度は230℃
〜270℃である。)よりも高融点のものを用い、第二
工程において再溶融しないように配慮していた。
In this case, if the solder used in the first step and the solder used in the second step have approximately the same melting point temperature, the soldering in the second step may cause the difference between the lead terminal and the terminal mounting electrode of the element. Soldering between the elements has the problem that when the part is heated, the solder from the first step remelts and flows out, causing the lead terminal to fall off from the element and short circuits occurring due to the flowing solder. For this reason, in the past (especially for electronic components with small heat capacity), the solder material for the second step (for example, 5n63-Pb37 solder has a melting point temperature of about 183°C, The temperature is 230℃
~270°C. ), and care was taken to avoid re-melting in the second step.

〔発明が解決しようとする課題〕[Problem to be solved by the invention]

上述のように、従来にあっては、第二工程で用いられる
はんだ材料よりも高融点のはんだを電子部品の製造段階
(第一工程)で使用しており、この場合第一、第二両工
程で使用されるはんだの融点差が大きいほどリード端子
とエレメントの端子取付用電極との間の耐熱性は向上す
る。ところが、両工程で使用されるはんだの融点差を大
きくするというこ゛とは、とりも直さず第一工程で使用
されるはんだの融点が高くなるということであり、当然
リード端子を端子取付用電極にはんだ付けする時の必要
温度も上昇し、電子部品のエレメントが高温に曝されて
熱的ダメージを受け、破損する恐れがある。従って、両
工程で使用されるはんだの融点差を大きくするにも限界
があった。
As mentioned above, conventionally, a solder with a higher melting point than the solder material used in the second process is used in the manufacturing stage (first process) of electronic components, and in this case, both the first and second solder The larger the difference in melting point of the solder used in the process, the better the heat resistance between the lead terminal and the terminal attachment electrode of the element. However, increasing the difference in the melting points of the solder used in both processes means that the melting point of the solder used in the first process becomes higher, and it is natural that the lead terminal should be used as the terminal mounting electrode. The required temperature for soldering also rises, and the elements of electronic components are exposed to high temperatures and may suffer thermal damage and breakage. Therefore, there is a limit to increasing the melting point difference between the solders used in both processes.

そこで、理想的には「はんだ付けする時には低融点であ
り、はんだ付けが終了したら高融点になるはんだ材料」
のようなものが望まれる。しかし、はんだ材料のはんだ
付は工程における変化は基本的には固相と液相との間の
可逆反応であり、組成変化を伴わないので、このような
ものは原理的に不可能である0例えば、5n63−Pb
37のはんだの場合では、はんだ付は前後での組成の変
化はなくて融点温度はいずれも183℃である。
Therefore, the ideal solder material is one that has a low melting point when soldering and has a high melting point once soldering is complete.
Something like this is desired. However, in the soldering process of solder materials, changes in the process are basically a reversible reaction between the solid phase and the liquid phase and do not involve changes in composition, so this is impossible in principle. For example, 5n63-Pb
In the case of No. 37 solder, there is no change in composition before and after soldering, and the melting point temperature is 183° C. in both cases.

また、はんだに代えて導電接着剤を用いることは、この
−解決案であるが、導電接着剤は耐熱性や導電性及び強
度の面で不安があり、また接着剤の硬化時間も長く、実
用段階では問題があった。
In addition, using conductive adhesive instead of solder is a solution to this problem, but conductive adhesive has concerns in terms of heat resistance, conductivity, and strength, and the curing time of the adhesive is long, making it impractical. There were problems at this stage.

よって、従来にあっては、第二工程におけるリード端子
の脱落やショートを防止するための有効な解決手段はな
かった。
Therefore, in the past, there has been no effective solution for preventing the lead terminals from falling off or short-circuiting in the second step.

ここに本発明は、リード端子をプリント基板などにはん
だ付けする時に、さらに一般的には加熱された時に、リ
ード端子がエレメントから脱落したり、ショートを発生
したりするのを有効に防止することのできる電子部品を
提供することを目的としている。
The present invention has an object to effectively prevent the lead terminal from falling off from the element or causing a short circuit when the lead terminal is soldered to a printed circuit board or the like, and more generally when the lead terminal is heated. The aim is to provide electronic components that can

〔課題を解決するための手段〕[Means to solve the problem]

このため本発明の電子部品にあっては、銅粉を添加した
はんだクリームによってリード端子をはんだ付けされて
いることを特徴としている。
For this reason, the electronic component of the present invention is characterized in that the lead terminals are soldered using solder cream containing copper powder.

〔作用〕[Effect]

しかして、リード端子をはんだ付けしているはんだクリ
ームに銅粉を添加しであるので、銅粉ははんだ付は時の
熱処理によってはんだ中のスズと金属間化合物を形成し
、はんだ中に分散する。
However, since copper powder is added to the solder cream used to solder the lead terminals, the copper powder forms an intermetallic compound with the tin in the solder during the heat treatment during soldering, and is dispersed in the solder. .

金属間化合物は一般に高融点(例えば、約1000℃)
であり、この高融点の金属間化合物がはんだ母材中に分
散することにより、加熱されて温度が上昇しても容易に
流動しない骨格の如きものがはんだ中に形成されること
になる。このため、たとえ母材のはんだが溶融しても、
この液相のはんだは表面張力ないし毛細管現象によって
銅とスズの金属間化合物の間に保持されてリード端子か
ら流れ出るのを防止される。そして、例えばリード端子
の基板へのはんだ付けが完了して温度が下がると、母材
のはんだも再び固化する。したがって、見掛は状ははん
だ付は後にはんだの融点が上昇したのと同様な効果を奏
するのである。また、銅粉の量を増量してゆくと、高融
点の金属間化合物の割合が増加するので、はんだの融点
が実質的に上昇することも期待できる。
Intermetallic compounds generally have a high melting point (e.g. about 1000°C)
When this high melting point intermetallic compound is dispersed in the solder base material, something like a skeleton is formed in the solder that does not easily flow even when heated and the temperature rises. Therefore, even if the base metal solder melts,
This liquid phase solder is held between the copper and tin intermetallic compounds by surface tension or capillary action and is prevented from flowing out from the lead terminals. Then, for example, when the soldering of the lead terminal to the board is completed and the temperature drops, the solder of the base material also solidifies again. Therefore, the apparent effect of soldering is similar to that of increasing the melting point of the solder. Further, as the amount of copper powder is increased, the proportion of high melting point intermetallic compounds increases, so it can be expected that the melting point of the solder will increase substantially.

〔実施例〕〔Example〕

以下、本発明の一実施例を添付図に基づいて説明する。 Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings.

はんだクリーム2は、スズSnと鉛pbを含んだ任意の
組成のはんだ粉3と、フラックスと溶剤を含んだペース
ト4とからなっており、適当量の銅粉1が添加されてい
る。即ち、第1図に示すように、ペースト4中にははん
だ粉3の粒子と銅粉1の粒子とが分散させられているが
、この状態でははんだ粉3中のスズと銅とは未だ金属間
化合物を形成していない。
The solder cream 2 consists of solder powder 3 having an arbitrary composition containing tin Sn and lead PB, and a paste 4 containing flux and a solvent, to which an appropriate amount of copper powder 1 is added. That is, as shown in FIG. 1, particles of solder powder 3 and particles of copper powder 1 are dispersed in paste 4, but in this state, tin and copper in solder powder 3 are still metal. No intermediate compounds are formed.

しかして、例えばこのはんだクリーム2を電子部品エレ
メントの端子取付用電極5とリード端子(図示せず)と
の間に塗布しくあるいは、両者を重ねた上に塗布し)、
このリード端子を保持させた電子部品をリフロー用の加
熱炉内を通過させて加熱することにより(あるいは、加
熱されなコテや熱風を当てることにより)はんだクリー
ム2を溶融させてはんだ付けを行う、このようにしては
んだ付は工程において熱処理されると、その際に銅が周
囲のスズと反応してCu3SnやCu6Sn5のような
Cu−5n金属間化合物6を生成する。ここで、銅粉1
の添加量ははんだ粉3の含有量に比べて少量であるので
、はんだ粉3の大部分は溶融後に再固化して塊状となる
が、はんだ粉3に含まれていたスズの一部は銅粉1と金
属間化合物6を形成し、この金属間化合物6の粒子は第
2図に示すように塊状のはんだ母材7中に分散させられ
る。こうして、銅粉1を添加したはんだクリーム2を用
いてはんだ付けをおこなうことにより、はんだの一部に
組成変化を生じさせることができるのである。
For example, the solder cream 2 may be applied between the terminal attachment electrode 5 of the electronic component element and the lead terminal (not shown), or may be applied on top of both,
Soldering is performed by passing the electronic component holding the lead terminal through a reflow heating furnace and heating it (or by applying an unheated iron or hot air) to melt the solder cream 2. In this way, when soldering is heat treated in the process, copper reacts with surrounding tin to form Cu-5n intermetallic compounds 6 such as Cu3Sn and Cu6Sn5. Here, copper powder 1
Since the amount added is small compared to the content of solder powder 3, most of the solder powder 3 re-solidifies after melting and becomes a lump, but some of the tin contained in the solder powder 3 is copper. An intermetallic compound 6 is formed with the powder 1, and the particles of the intermetallic compound 6 are dispersed in a bulk solder base material 7 as shown in FIG. In this way, by performing soldering using the solder cream 2 to which the copper powder 1 has been added, a compositional change can be caused in a part of the solder.

なお、金属間化合物は、はんだ付は時に生成していくが
、このためはんだ付は時間は長くなる。これが電子部品
の耐熱性の面などで問題となる場合には、金属間化合物
の生成反応は低温でも進むので、低温(例えば100〜
150℃)での熱処理などでも同様な効果を得ることが
できる。
Note that intermetallic compounds are sometimes generated during soldering, and for this reason, soldering takes a long time. If this becomes a problem in terms of heat resistance of electronic parts, the formation reaction of intermetallic compounds proceeds even at low temperatures, so
A similar effect can be obtained by heat treatment at 150°C.

ここで、銅と反応していない母材7のはんだ5n−pb
ははんだ付は前と同じ融点温度を有しているが、Cu−
5n金属間化合物6は約700℃程度の高い融点温度を
有しているので、例えば電子部品のリード端子を基板な
どにはんだ付けする際などに加熱されて母材7部分のは
んだが再溶融しても、金属間化合物6は熔融せず、周囲
の溶融はんだを表面張力ないし毛細管現象によって保持
し、溶融はんだの流出を抑える。そして、再び冷却され
ると母材7のはんだは再び固化して元の状態に戻り、リ
ード端子をエレメントに保持させる。したがって、はん
だの融点温度まで加熱されると、実際にははんだは溶融
するが、金属間化合物6に保持されて流れ出さないので
、見掛は上ははんだ付は後にはんだの融点が高くなった
のと同じ効果を得ることができるのである。また、銅粉
1の添加量を増すことによってはんだ母材7中の金属間
化合物の割合が増加するので、全体として実際に高融点
化されることも期待される。
Here, the solder 5n-pb of base material 7 that has not reacted with copper
soldering has the same melting point temperature as before, but Cu-
Since the 5n intermetallic compound 6 has a high melting point temperature of approximately 700°C, it is heated when, for example, lead terminals of electronic components are soldered to a board, etc., and the solder in the base material 7 is remelted. However, the intermetallic compound 6 does not melt and holds the surrounding molten solder by surface tension or capillarity, thereby suppressing the outflow of the molten solder. Then, when the base material 7 is cooled again, the solder on the base material 7 solidifies again and returns to its original state, thereby holding the lead terminal in the element. Therefore, when heated to the melting point temperature of the solder, the solder actually melts, but it is held in the intermetallic compound 6 and does not flow out, so it appears that the melting point of the solder is higher after soldering. You can get the same effect as Moreover, since the proportion of intermetallic compounds in the solder base material 7 increases by increasing the amount of copper powder 1 added, it is expected that the melting point as a whole will actually be increased.

なお、第3図には本発明の詳細な説明するための参考例
を示しである。これは銅層8の表面に従来の5n63−
Pb37などのはんだ9によってはんだ付は行った状態
を示している。従来のはんだ9を用いてはんだ付けを行
った場合にも、銅層8からはんだ9中に銅が溶解しては
んだ9中のスズと反応し、銅層8とはんだ9との界面に
Cu3Snのような金属間化合物層10やCu6Sn5
のような金属間化合物層11を生成することがあるが、
これはミクロ的な膜層であり、マクロ的にはんだ9部分
には組成変化は生じ゛ていない、したがって、このはん
だ9が基板へのはんだ付は時などに加熱され、融点以上
になると、溶融して液状化し、リード端子を保持するだ
けの強度を保ち得す、リード端子の脱落やショートなど
を生じる。これに対し、上記の銅粉1を添加したはんだ
クリームでは、銅粉1が初めから全体に分散させられて
いるので、はんだ付は後に生成される金属間化合物6も
はんだ母材7中に分散しており、溶融したはんだの流出
を抑えることができるのである。
Note that FIG. 3 shows a reference example for explaining the present invention in detail. This is a conventional 5n63-
A state in which soldering is performed using solder 9 such as Pb37 is shown. Even when soldering is performed using the conventional solder 9, copper from the copper layer 8 melts into the solder 9 and reacts with the tin in the solder 9, resulting in the formation of Cu3Sn at the interface between the copper layer 8 and the solder 9. Intermetallic compound layer 10 such as Cu6Sn5
Although an intermetallic compound layer 11 such as
This is a microscopic film layer, and there is no compositional change in the solder 9 part from a macroscopic perspective. Therefore, when this solder 9 is soldered to a board, it will be heated and if the temperature exceeds its melting point, it will melt. This causes the lead terminals to fall off or short-circuit, even though they are not strong enough to hold the lead terminals. On the other hand, in the solder cream to which copper powder 1 is added, the copper powder 1 is dispersed throughout from the beginning, so during soldering, the intermetallic compounds 6 that are generated later are also dispersed in the solder base material 7. This makes it possible to suppress the flow of molten solder.

なお、はんだ粉に添加する金属は、銅に限らず、はんだ
と高融点の金属間化合物を形成するものならなんでも良
く、例えば銀でも可能である。
Note that the metal added to the solder powder is not limited to copper, and may be any metal that forms an intermetallic compound with a high melting point with the solder, such as silver.

〔発明の効果〕〔Effect of the invention〕

本発明によれば、銅粉を添加したはんだクリームを用い
てリード端子をはんだ付けしであるので、母材のはんだ
中にはスズと銅との金属間化合物が分散しており、電子
部品(特に、リード端子)が加熱されてたとえ母材のは
んだが再溶融してもはんだがリード端子から流れ出るこ
とがなく、リード端子の脱落や流れたはんだによるショ
ートを防止することができる。また、銅粉の添加量によ
っては、はんだ付は後の融点上昇を期待できる。更に、
従来よりも融点の低いはんだを用いることができるので
、はんだ付は時に電子部品を高温に曝して熱的な劣化や
損傷を与えることもない。
According to the present invention, since the lead terminals are soldered using solder cream containing copper powder, intermetallic compounds of tin and copper are dispersed in the solder base material, and electronic components ( In particular, even if the base material solder remelts when the lead terminals are heated, the solder will not flow out from the lead terminals, and it is possible to prevent the lead terminals from falling off and short circuits due to flowing solder. Furthermore, depending on the amount of copper powder added, it can be expected that the melting point will increase after soldering. Furthermore,
Since a solder with a lower melting point than conventional solders can be used, soldering does not sometimes expose electronic components to high temperatures, causing thermal deterioration or damage.

【図面の簡単な説明】[Brief explanation of the drawing]

第1図は本発明の一実施例に係るはんだクリームの模式
図、第2図は同上のはんだクリームを用いてはんだ付け
を行った状B3示す断面図、第3図は参考例のはんだ付
は状態を示す断面図である。 1・・・銅粉、2・・・はんだクリーム。
Fig. 1 is a schematic diagram of a solder cream according to an embodiment of the present invention, Fig. 2 is a cross-sectional view showing B3 in which soldering is performed using the same solder cream, and Fig. 3 is a schematic diagram of a soldering cream according to a reference example. It is a sectional view showing a state. 1...Copper powder, 2...Solder cream.

Claims (1)

【特許請求の範囲】[Claims] (1)銅粉を添加したはんだクリームによってリード端
子をはんだ付けされていることを特徴とする電子部品。
(1) An electronic component characterized by having lead terminals soldered with solder cream containing copper powder.
JP63055712A 1988-03-09 1988-03-09 Electronic part Pending JPH01230213A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP63055712A JPH01230213A (en) 1988-03-09 1988-03-09 Electronic part

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP63055712A JPH01230213A (en) 1988-03-09 1988-03-09 Electronic part

Publications (1)

Publication Number Publication Date
JPH01230213A true JPH01230213A (en) 1989-09-13

Family

ID=13006489

Family Applications (1)

Application Number Title Priority Date Filing Date
JP63055712A Pending JPH01230213A (en) 1988-03-09 1988-03-09 Electronic part

Country Status (1)

Country Link
JP (1) JPH01230213A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010050455A1 (en) * 2008-10-28 2010-05-06 京セラ株式会社 Thermoelectric module
JP2021048292A (en) * 2019-09-19 2021-03-25 Tdk株式会社 Ceramic electronic component
JP2021068861A (en) * 2019-10-28 2021-04-30 Tdk株式会社 Ceramic electronic component
JP2021068862A (en) * 2019-10-28 2021-04-30 Tdk株式会社 Ceramic electronic component

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010050455A1 (en) * 2008-10-28 2010-05-06 京セラ株式会社 Thermoelectric module
JP2010108958A (en) * 2008-10-28 2010-05-13 Kyocera Corp Thermoelectric module, and method of manufacturing the same
JP2021048292A (en) * 2019-09-19 2021-03-25 Tdk株式会社 Ceramic electronic component
JP2021068861A (en) * 2019-10-28 2021-04-30 Tdk株式会社 Ceramic electronic component
JP2021068862A (en) * 2019-10-28 2021-04-30 Tdk株式会社 Ceramic electronic component

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