JPH0344996A - Soldering method for multiple-port component - Google Patents
Soldering method for multiple-port componentInfo
- Publication number
- JPH0344996A JPH0344996A JP17906789A JP17906789A JPH0344996A JP H0344996 A JPH0344996 A JP H0344996A JP 17906789 A JP17906789 A JP 17906789A JP 17906789 A JP17906789 A JP 17906789A JP H0344996 A JPH0344996 A JP H0344996A
- Authority
- JP
- Japan
- Prior art keywords
- solder
- cream solder
- soldering
- leads
- soldered
- 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.)
- Granted
Links
- 238000005476 soldering Methods 0.000 title claims abstract description 28
- 238000000034 method Methods 0.000 title claims description 12
- 229910000679 solder Inorganic materials 0.000 claims abstract description 67
- 239000006071 cream Substances 0.000 claims abstract description 43
- 239000000203 mixture Substances 0.000 claims abstract description 15
- 239000000843 powder Substances 0.000 claims description 8
- 238000002156 mixing Methods 0.000 claims description 2
- 238000005303 weighing Methods 0.000 claims description 2
- 239000011248 coating agent Substances 0.000 abstract description 3
- 238000000576 coating method Methods 0.000 abstract description 3
- 230000008018 melting Effects 0.000 abstract description 3
- 238000002844 melting Methods 0.000 abstract description 3
- 230000015572 biosynthetic process Effects 0.000 abstract description 2
- 238000010276 construction Methods 0.000 abstract 1
- 230000005496 eutectics Effects 0.000 description 8
- 230000007547 defect Effects 0.000 description 7
- 238000010438 heat treatment Methods 0.000 description 7
- 239000000155 melt Substances 0.000 description 5
- 230000000052 comparative effect Effects 0.000 description 4
- 230000004907 flux Effects 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- 239000007787 solid Substances 0.000 description 3
- 230000008023 solidification Effects 0.000 description 3
- 238000007711 solidification Methods 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910000978 Pb alloy Inorganic materials 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- 235000014676 Phragmites communis Nutrition 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/30—Assembling printed circuits with electric components, e.g. with resistor
- H05K3/32—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
- H05K3/34—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
- H05K3/341—Surface mounted components
- H05K3/3421—Leaded components
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/30—Assembling printed circuits with electric components, e.g. with resistor
- H05K3/32—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
- H05K3/34—Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
- H05K3/3457—Solder materials or compositions; Methods of application thereof
Landscapes
- Electric Connection Of Electric Components To Printed Circuits (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分封〕
本発明はＱ Ｆ Ｐ （Ｑｕａｄ Ｆｌａｔ Ｐａｃｋ
ａｇｅ Ｉｃ）やＳｏ １ Ｃ（Ｓｍａｌｌ Ｑｕｔｌ
ｅｔ ＩＣ）のようにリードが多数設置された多端子部
品とプリント基板とをクリームはんだではんだ付けする
方法に関する。[Detailed description of the invention] [Industrial usage packaging] The present invention is a QFP (Quad Flat Pack).
age Ic) and So 1 C (Small Qutl
This invention relates to a method of soldering a multi-terminal component with many leads such as an IC) and a printed circuit board using cream solder.
多端子部品とプリント基板とをクリームはんだではんだ
付けするには、多端子部品のはんだ付け部と一致すると
ころに穴が穿設された多孔スクリーンを用い、該穴とプ
リント基板のはんだ付け部とが一致するようにしてスク
リーンをプリント基板上に置き、その上からクリームは
んだをスキージで掻いて穴にクリームはんだを充填した
後スクリーンを取り外す。するとクリームはんだがプリ
ント基板のはんだ付け部に印刷塗布される。これをリフ
ロー炉、熱風、蒸気槽、レーザー光線等で加熱して多端
子部品とプリント基板とをはんだ付けするものである。To solder a multi-terminal component and a printed circuit board with cream solder, use a porous screen with holes drilled in locations that correspond to the soldered areas of the multi-terminal component, and connect the holes to the soldered areas of the printed circuit board. Place the screen on the printed circuit board so that they match, scrape cream solder from above with a squeegee, fill the holes with cream solder, and then remove the screen. Cream solder is then printed and applied to the soldered areas of the printed circuit board. This is heated in a reflow oven, hot air, steam bath, laser beam, etc. to solder the multi-terminal component and the printed circuit board.
ところで近時の多端子部品は多機能化されてきているこ
とからリードが多数設置されており、しかもそれが小型
となっているため、リード間隔も非常に狭くなってきて
いる（ファインピッチという）。ファインピッチの電子
部品を搭載するプリント基板に対して従来の多孔スクリ
ーンを用いてクリームはんだを印刷塗布すると、穴が小
さいためクリームはんだが充填されなかったり、穴に充
填されてもプリント基板に付着しないという印刷不良を
起こすことがあった。また、多孔スクリーンは小さな穴
とプリント基板の小さなはんだ付け部とを完全に一致さ
せることが難しく、印刷ずれを起こすことが往々にして
あった。By the way, recent multi-terminal components are becoming more multi-functional, so many leads are installed, and as they are becoming smaller, the lead spacing is becoming very narrow (referred to as fine pitch). . When using a conventional porous screen to print and apply cream solder to a printed circuit board with fine-pitch electronic components, the holes are too small to be filled with cream solder, or even if the holes are filled, the cream solder does not adhere to the printed circuit board. Printing defects may occur. In addition, in the case of a porous screen, it is difficult to completely match the small holes with the small soldered portions of the printed circuit board, which often causes printing misalignment.
このようなファインピッチの印刷を容易にする方法とし
て、並列した多数のはんだ付け部全部に連続してクリー
ムはんだを印刷する方法（−文字方法という）が提案さ
れている（参照、特公昭６０−５８６００号）。As a method to facilitate fine-pitch printing, a method has been proposed in which cream solder is continuously printed on all of the solder joints in parallel (referred to as the "letter method") (see Japanese Patent Publication No. 1983-1983). No. 58600).
一般に、電子部品とプリント基板のはんだ付けには、は
んだ付け強さやはんだ付け性の点から６３Ｓｎ−Ｐｂの
共晶はんだ、或いはこの共晶近辺のはんだが用いられて
いるが、−文字方法においてもこの共晶又は共晶近辺の
クリームはんだが用いられていた。Generally, 63Sn-Pb eutectic solder or a solder close to this eutectic is used for soldering electronic components and printed circuit boards in terms of soldering strength and solderability. This eutectic or near-eutectic cream solder has been used.
たしかに−文字方法はクリームはんだの印刷塗布不良が
無く、またスクリーンとプリント基板の位置合わせが容
易であるが、クリームはんだ印刷塗布後、多端子部品を
搭載して加熱すると、多端子部品の並列したリードの中
央よりにブリッヂを形成してしまうことがあった。It is true that with the letter method, there are no defects in the printing and coating of cream solder, and it is easy to align the screen and the printed circuit board. Sometimes a bridge was formed closer to the center of the reed.
本発明は、−文字方法において中央よりのリードにブリ
ッヂを形成させることがないはんだ付け方法を提供する
ことにある。SUMMARY OF THE INVENTION An object of the present invention is to provide a soldering method in which a bridge is not formed in the lead from the center in the -character method.
本発明者らが共晶のクリームはんだを用い九−文字方法
におけるブリッヂの形成原因について検討を重ねた結果
、クリームはんだの溶融時、表面張力が瞬時に働くため
であることが分かった。つまり、共晶はんだは溶融時、
１８３℃で固体から直ぐに液体となるため、液体の表面
張力の働きが直ぐに始まる。従って、直線状に連続塗布
されにクリームはんだは溶融時、両端が表面張力で中央
に引っ張られ、中央にはんだが多量に集まるため、それ
が隣接したリードに跨ってしまいブリッヂとなってしま
うものである。As a result of repeated studies by the present inventors regarding the cause of bridge formation in the nine-letter method using eutectic cream solder, it was found that this is due to the instantaneous action of surface tension when the cream solder melts. In other words, when eutectic solder melts,
Since it changes from a solid to a liquid immediately at 183°C, the surface tension of the liquid begins to act immediately. Therefore, when cream solder is applied continuously in a straight line and melts, both ends are pulled toward the center by surface tension, and a large amount of solder gathers in the center, which can straddle adjacent leads and form a bridge. be.
本発明者らは上記現象に鑑み、クリームはんだの溶融時
、固体から液体になるのに時間がかかれば表面張力の働
きが遅くなって両端のはんだを中央に引き付けることが
なくなることに着目して本発明を完成させた。In view of the above phenomenon, the present inventors focused on the fact that when cream solder melts, if it takes time for it to change from solid to liquid, the surface tension will slow down and the solder at both ends will no longer be attracted to the center. The present invention has been completed.
５ｎ−Ｐｂ合金で固体から液体への変態時、凝固範囲を
長くするためには共晶から離れた組成にすればよいが、
共晶から離れると前述の如くはんだ付け性、強度等に問
題があるばかりでなく液相線温度が上がるため、はんだ
付け温度を上げざるを得す電子部品に悪影響を与えるこ
とになる。When transforming from a solid to a liquid in a 5n-Pb alloy, in order to extend the solidification range, the composition should be away from the eutectic one.
If it moves away from the eutectic, not only will there be problems with solderability, strength, etc. as described above, but also the liquidus temperature will rise, which will have an adverse effect on electronic components that require higher soldering temperatures.
ところで特開昭６３−１５４２８８号には組成の異なる
二種の粉末はんだを混和して溶融時に共晶組成となるよ
うにしたクリームはんだが提案されている。該クリーム
はんだは凝固範囲の長い二種の粉末を混和したものでペ
ーパー・フェーズ・ソルダリングにおいてチップ部品が
立上がったり、リードだけにはんだが付着してはんだ付
け部が開いてしまうのを防ぐためのものである。その組
成は別設限定されてなく、二種の合金組成が異なってい
さえすればよいとされている。By the way, JP-A-63-154288 proposes a cream solder in which two powdered solders having different compositions are mixed to form a eutectic composition when melted. This cream solder is a mixture of two types of powders that have a long solidification range, and is used to prevent chip components from standing up during paper phase soldering and to prevent solder joints from sticking to the leads and opening. It is something. The composition is not particularly limited, and it is sufficient that the two alloy compositions are different.
本発明者らは該クリームはんだにおいて、一種の合金を
成る所定の組成にすると凝固範囲が適当な長さとなり中
央部にブリッヂを形成しないことを見出して本発明を完
成させた。The present inventors have completed the present invention by discovering that when the cream solder has a predetermined composition consisting of a type of alloy, the solidification range becomes an appropriate length and no bridge is formed in the center.
本発明は、Ｓｎｌ 〜３０ｆｆｉｆ１％、残部Ｐｂ＆ｆ
ｌ成の粉末はんだと他の組成の粉末はんだを混和して溶
融した時、所定の組成となるように、それぞれの粉末は
んだを秤量配合して製造したクリームはんだを多数のは
んだ付け部に直線状に連続塗布し、該塗布部に多端子部
品のリードをｔ？Ａａした後、クリームはんだを溶融さ
せてはんだ付けすることを特徴とする多端子部品のはん
だ付け方法である。In the present invention, Snl ~30ffif1%, balance Pb&f
The cream solder produced by weighing and blending each powder solder is applied to a large number of soldered parts in a straight line so that when mixed and melted, a powder solder of one composition and a powder solder of another composition will have a predetermined composition. Continuously apply the coating to the applied area, and connect the lead of the multi-terminal component to the applied area. This is a method of soldering multi-terminal parts, which is characterized by melting cream solder and soldering after applying Aa.
本発明において、一方の粉末はんだの５ｎｆｆｉが１重
量％より少ないと粉末はんだの融点が高くなり過ぎて完
全に溶けるまでに時間が掛かって生産性が悪くなる。ま
たＳｎ量が３０重量％を超えると粉末はんだの溶融が早
くなり、表面張力が早く作用してブリッヂを形成させて
しまう。In the present invention, if the 5nffi of one of the powdered solders is less than 1% by weight, the melting point of the powdered solder will be too high and it will take time to completely melt, resulting in poor productivity. Moreover, if the amount of Sn exceeds 30% by weight, the powder solder melts quickly, and the surface tension acts quickly to form a bridge.
はんだ付けに使用した電子部品、スクリーン、加熱装置
および加熱条件は下記の如くである。The electronic components, screen, heating device, and heating conditions used for soldering are as follows.
■電子部品：リード巾０．１８ｍｍ
ノードピッチ０．５ｍｍ
リード数６４本のＱＦＰ
■プリント基板：上記ＱＦＰを１０個搭載できろ紙フエ
ノール製プリント基板
■長孔スクリーン二上記プリント基板のはんだ付け部に
クリームはんだを直
線状に連続塗布できる長孔を
有するメタルスクリーン（板
厚０．２ｍｍ、長孔１１．５ Ｘ Ｏ，８＋ｎｍ）
■多孔スクリーン二上記プリント基板の各はんだ付け部
にクリームはんだを
塗布できる孔が多数穿設され
たメタルスクリーン（板厚
０．２ｍｍ、孔Ｘ １．２５Ｘ Ｏ，２５ｍｍ）■加熱
装置：加熱域２ｍの遠赤外線式リフロー炉
■加熱条件：２００℃以上、１分間
実施例１
０クリームはんだ
ペースト状フラックス ２８ｇ
○クリームはんだの塗布とはんだ付け
上記クリームはんだを■のプリント基板上に■の長孔ス
クリーンで印刷塗布し、■のＱＦＰを搭載した後、■の
りフロー炉と■の加熱条件ではんだを付け行った。■Electronic components: Lead width 0.18mm, Node pitch 0.5mm, QFP with 64 leads ■Printed circuit board: Printed circuit board made of filter paper phenol that can mount 10 of the above QFPs ■Long hole screen 2 Cream on the soldering part of the above printed circuit board Metal screen with long holes that allow solder to be applied continuously in a straight line (plate thickness 0.2mm, long holes 11.5 x O, 8+nm) ■ Porous screen 2 Holes that allow cream solder to be applied to each soldering part of the above printed circuit board Metal screen with many holes (plate thickness 0.2mm, holes x 1.25X O, 25mm) ■Heating device: Far infrared reflow oven with heating area of 2m ■Heating conditions: 200℃ or higher, 1 minute Example 1 0 Cream solder paste flux 28g ○ Cream solder application and soldering The above cream solder is printed and applied on the printed circuit board (■) using the long hole screen (■), and after mounting the QFP (■), Soldering was carried out under heating conditions.
Ｏ結果
クリームはんだの印刷不良はなく、はんだ付け部のブリ
ッヂ数はＯであった。O Result: There was no printing defect with the cream solder, and the number of bridges in the soldered area was O.
実施例２
０クリームはんだ
ペースト状フラックス
３ｇ
○クリームはんだの塗布とはんだ付け
実施例１と同様
○結果
クリームはんだの印刷不良はなく、はんだ付け後のブリ
ッヂ数はＯであった。Example 2 0 Cream solder paste flux 3 g ○ Cream solder application and soldering Same as Example 1 ○ Result There was no printing defect with the cream solder, and the number of bridges after soldering was O.
比較例１
０クリームはんだ
６３Ｓｎ−Ｐｂ粉（２５０メツシ１）１００ｇペースト
状フラックス Ｉ１ｇ
○クリームはんだの塗布とはんだ付け
上記クリームはんだな■のプリント基板上に■の長孔ス
クリーンで印刷塗布し、■のＱＦＰを搭載した後、■の
りフロー炉と■の加熱条件ではんだ付けを行った。Comparative Example 1 0 Cream solder 63Sn-Pb powder (250 mesh 1) 100g Paste flux I1g ○Cream solder application and soldering Print and apply the cream solder (■) on the printed circuit board (■) using the long hole screen (■). After mounting the QFP, soldering was carried out in a glue flow furnace and under the heating conditions of ■.
○結果
クリームはんだの印刷不良はなかったが、はんだ付け後
のブリッヂの数は２３個であった。○Results Although there were no printing defects with the cream solder, the number of bridges after soldering was 23.
比較例２
０クリームはんだ
６０Ｓｒｒ ｌＡｇ−Ｐｂ粉（２５０メツシユ）１００
ｇペースト状フラックス ！、１ｇ○クリームは
んだの塗布とはんだ付け
上記クリームはんだを■のプリント基板上に■の多孔ス
クリーンを用いて塗布し、比較例１と同様のはんだ付け
を行った。Comparative Example 2 0 Cream solder 60Srr 1Ag-Pb powder (250 mesh) 100
g Paste flux! , 1g Cream solder application and soldering The above cream solder was applied onto the printed circuit board (■) using a porous screen (■), and soldering was carried out in the same manner as in Comparative Example 1.
○結果
印刷不良が７箇所あった。ブリッヂ数はＯｏ〔発明の効
果〕
本発明によれば、リードが細く、リード間隔の狭いファ
インピッチの電子部品をクリームはんだではんだ付けす
るに際して、印刷不良がないばかりか、リード間にブリ
ッヂを形成させることがないため、信頼あるはんだ付け
が行えるものである。○Results: There were 7 printing defects. The number of bridges is Oo [Effects of the Invention] According to the present invention, when soldering fine-pitch electronic components with thin leads and narrow lead spacing using cream solder, not only is there no printing defect, but bridges are formed between the leads. Since the soldering process does not occur, reliable soldering can be performed.
Claims (1)
組成の粉末はんだを混和して溶融した時、所定の組成と
なるように、それぞれの粉末はんだを秤量配合して製造
したクリームはんだを多数のはんだ付け部に直線状に連
続塗布し、該塗布部に多端子部品のリードを載置した後
、クリームはんだを溶融させてはんだ付けすることを特
徴とする多端子部品のはんだ付け方法。A large number of cream solders were manufactured by weighing and blending each powder solder so that when a powdered solder with a composition of Sn 1 to 30% by weight and the balance Pb and a powdered solder of another composition were mixed and melted, a predetermined composition was obtained. A method for soldering a multi-terminal component, characterized in that cream solder is applied continuously in a straight line to a soldering part, and after placing a lead of the multi-terminal part on the applied part, the cream solder is melted and soldered.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1179067A JPH0783178B2 (en) | 1989-07-13 | 1989-07-13 | Soldering method for multi-terminal parts |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1179067A JPH0783178B2 (en) | 1989-07-13 | 1989-07-13 | Soldering method for multi-terminal parts |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0344996A true JPH0344996A (en) | 1991-02-26 |
| JPH0783178B2 JPH0783178B2 (en) | 1995-09-06 |
Family
ID=16059526
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1179067A Expired - Fee Related JPH0783178B2 (en) | 1989-07-13 | 1989-07-13 | Soldering method for multi-terminal parts |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0783178B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0715134A (en) * | 1991-08-02 | 1995-01-17 | Senju Metal Ind Co Ltd | Method for soldering surface mount electronic parts |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6058600A (en) * | 1983-08-02 | 1985-04-04 | ユナイテッド キングドム アトミック エナ↓−ヂイ オ↓−ソリテイ | Method of encapsulating waste |
| JPS63154288A (en) * | 1986-10-03 | 1988-06-27 | テキサス インスツルメンツ インコーポレイテツド | Solder paste |
-
1989
- 1989-07-13 JP JP1179067A patent/JPH0783178B2/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6058600A (en) * | 1983-08-02 | 1985-04-04 | ユナイテッド キングドム アトミック エナ↓−ヂイ オ↓−ソリテイ | Method of encapsulating waste |
| JPS63154288A (en) * | 1986-10-03 | 1988-06-27 | テキサス インスツルメンツ インコーポレイテツド | Solder paste |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0715134A (en) * | 1991-08-02 | 1995-01-17 | Senju Metal Ind Co Ltd | Method for soldering surface mount electronic parts |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0783178B2 (en) | 1995-09-06 |
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