JPH0846333A - Cleaning of printed board - Google Patents

Cleaning of printed board

Info

Publication number
JPH0846333A
JPH0846333A JP17658494A JP17658494A JPH0846333A JP H0846333 A JPH0846333 A JP H0846333A JP 17658494 A JP17658494 A JP 17658494A JP 17658494 A JP17658494 A JP 17658494A JP H0846333 A JPH0846333 A JP H0846333A
Authority
JP
Japan
Prior art keywords
copper pattern
cleaning
printed board
aqueous solution
alkali
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
JP17658494A
Other languages
Japanese (ja)
Inventor
Hisao Tanaka
久雄 田中
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.)
Fujitsu Ltd
Original Assignee
Fujitsu 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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP17658494A priority Critical patent/JPH0846333A/en
Publication of JPH0846333A publication Critical patent/JPH0846333A/en
Pending legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23GCLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
    • C23G1/00Cleaning or pickling metallic material with solutions or molten salts
    • C23G1/14Cleaning or pickling metallic material with solutions or molten salts with alkaline solutions
    • C23G1/20Other heavy metals

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
  • Manufacturing Of Printed Wiring (AREA)

Abstract

PURPOSE:To make sulfate ions reduce to zero from the upper part of a copper pattern to make it possible to perform a good surface treatment of a printed board by a method wherein after an oxide film removal treatment of the copper pattern of the printed board is performed, the printed board is cleaned with an alkalifine aqueous solution. CONSTITUTION:An alkali cleaning process is provided after a rinsing process subsequent to a soft etching. Moreover, a rinsing process is provided after the alkali cleaning process. The interior of a cleaning tank, for example, is filled with an alkaline aqueous solution, which is used in an alkali cleaning, and the alkali cleaning is performed by dipping a printed board in the cleaning tank. Sulfate ions remaining on a copper pattern after the soft etching undergo neutralization with an alkali at the time of the alkali cleaning to turn into salt and the salt is deposited in the aqueous solution or is dissolved in the aqueous solution. As a result, the sulfate ions are reduced to zero from the upper part of the copper pattern and a good final surface treatment of the printed board becomes possible. Accordingly, a soldering defect can be prevented from being generated.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、プリント基板の製作に
際して銅パターンの酸化膜除去処理を行った後に実施す
る基板の洗浄方法に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of cleaning a substrate, which is carried out after a copper pattern is subjected to an oxide film removing process in manufacturing a printed circuit board.

【0002】近年、プリント板ユニットの無洗浄化に伴
い、半田付け用フラックスについても、半田付け後の残
渣を少なくするために低固形分化し、また残渣の信頼性
を確保するため低活性化している。同時に搭載部品の小
型・高密度化も進行しており、半田付け条件の制約が厳
しくなる一方で、半田付け品質の維持・向上が要求され
ている。
[0002] In recent years, with the elimination of cleaning of printed board units, the soldering flux is also reduced in solidification in order to reduce the residue after soldering, and is also activated in order to ensure the reliability of the residue. There is. At the same time, the mounting components are becoming smaller and higher in density, and the restrictions on soldering conditions are becoming more severe, while maintaining and improving soldering quality is required.

【0003】このため、窒素雰囲気中半田付け技術やフ
ラックス成分の新活性剤配合技術等により、半田付け品
質の向上を図っているが、半田付け資材となるプリント
基板の品質(耐酸化性等)についても向上を図ることが
望ましい。
Therefore, the soldering quality is improved by the soldering technique in a nitrogen atmosphere, the new activator blending technique of the flux component, and the like. It is also desirable to improve

【0004】[0004]

【従来の技術】図5はプリント基板の従来の製造工程の
一部を示す図である。先ず、プリント基板上に予め定め
られた形状の銅パターンが形成され、次いで、銅パター
ンの酸化膜除去を行うためにソフトエッチングが行われ
る。
2. Description of the Related Art FIG. 5 is a diagram showing a part of a conventional manufacturing process of a printed circuit board. First, a copper pattern having a predetermined shape is formed on a printed board, and then soft etching is performed to remove the oxide film of the copper pattern.

【0005】ソフトエッチングでは、例えば硫酸・過酸
化水素系のソフトエッチング液にプリント基板を浸漬し
或いはプリント基板にソフトエッチング液をシャワーす
ることで銅パターン上の酸化膜が除去される。
In the soft etching, the oxide film on the copper pattern is removed by immersing the printed board in a soft etching solution of sulfuric acid / hydrogen peroxide system or by showering the soft etching solution on the printed board.

【0006】ソフトエッチングの後、ソフトエッチング
液を除去するために、例えば純水を用いて洗浄が行われ
る。その後、ソルダーコートやプリフラックス処理等の
最終表面処理が行われる。
After the soft etching, for example, pure water is used for cleaning in order to remove the soft etching solution. After that, final surface treatment such as solder coat or preflux treatment is performed.

【0007】[0007]

【発明が解決しようとする課題】ソフトエッチング液中
に通常多量に含有される硫酸イオン(SO4 - )は、酸
化膜除去によってミクロレベルで凹凸となった銅パター
ン表面に付着し易い性質を持っている。また、硫酸イオ
ンは水洗では完全に除去することができず、銅パターン
の表面に分子単位で残留してしまう。
THE INVENTION Problems to be Solved] Usually in soft etching solution contains large amounts is the sulfate ion (SO 4 -) may have a property of easily adhering to the copper pattern surface became uneven at the micro level by oxide film removal ing. Further, the sulfate ions cannot be completely removed by washing with water, and remain on the surface of the copper pattern in molecular units.

【0008】プリント基板の銅パターン表面に硫酸イオ
ンが残留したまま最終表面処理を行うと、硫酸イオンは
表面処理膜と銅表面の間に存在することとなる。そこか
ら酸化銅が生成され、温度・湿度の要因で反応速度は異
なるが、大気中の酸素と反応して酸化が進行し、銅酸化
物がパターン上に生成される。
When the final surface treatment is performed with the sulfate ions remaining on the copper pattern surface of the printed board, the sulfate ions will exist between the surface-treated film and the copper surface. Copper oxide is generated from there, and the reaction rate varies depending on the factors of temperature and humidity, but it reacts with oxygen in the atmosphere to proceed with oxidation, and copper oxide is generated on the pattern.

【0009】ソルダーコートや半田めっき等の銅パター
ンを金属でコートする処理では、大気と完全に遮断され
るため酸化の促進は抑えられるが、樹脂系やキレート系
プリフラックス処理ではコート膜が金属ほど強固でな
く、銅パターン上にゴミ、酸化物等の不純物があると適
正なコート厚が得られず、酸化防止効果が不十分とな
り、酸化が促進する。
In the process of coating the copper pattern with a metal such as solder coating or solder plating, the oxidation is suppressed because it is completely shielded from the atmosphere. If the copper pattern is not strong and has impurities such as dust and oxides on the copper pattern, a proper coat thickness cannot be obtained, the antioxidation effect becomes insufficient, and oxidation is accelerated.

【0010】また、プリント基板を高温高湿の環境で長
時間放置すると、銅パターン上の酸化物が成長し、プリ
ント基板の半田付け時の障害となり、半田付け不良とな
る。残留した硫酸イオンから酸化銅が生成される反応式
を参考までに下記しておく。
If the printed circuit board is left in a high temperature and high humidity environment for a long time, the oxide on the copper pattern grows, which becomes an obstacle when soldering the printed circuit board, resulting in poor soldering. The reaction formula for producing copper oxide from the remaining sulfate ion is shown below for reference.

【0011】Cu2+ + SO4 2- → CuSO4 CuSO4 + 2H2 O → Cu(OH)2 + 2
+ + SO4 2- Cu(OH)2 → CuO + H2 O よって、本発明の目的は、半田付け不良を防止すること
ができるプリント基板の洗浄方法を提供することにあ
る。
Cu 2+ + SO 4 2- → CuSO 4 CuSO 4 + 2H 2 O → Cu (OH) 2 + 2
H + + SO 4 2- Cu (OH) 2 → CuO + H 2 O Therefore, an object of the present invention is to provide a method for cleaning a printed circuit board, which can prevent defective soldering.

【0012】[0012]

【課題を解決するための手段】本発明のプリント基板の
洗浄方法は、プリント基板の銅パターンの酸化膜除去処
理を行った後、プリント基板をアルカリ性水溶液で洗浄
するようにしたものである。
The method of cleaning a printed circuit board according to the present invention comprises cleaning the printed circuit board with an alkaline aqueous solution after removing the oxide film of the copper pattern of the printed circuit board.

【0013】[0013]

【作用】本発明方法においては、ソフトエッチング後に
銅パターン上に残留した硫酸イオンは、アルカリ洗浄時
にアルカリと中和反応して塩となり、析出し或いは水に
溶解するので、硫酸イオンが銅パターン上から消滅して
良好な表面処理が可能となる。
In the method of the present invention, the sulfate ions remaining on the copper pattern after the soft etching are neutralized with the alkali during the alkali cleaning to form a salt, which is precipitated or dissolved in water. Therefore, it becomes possible to perform a good surface treatment.

【0014】[0014]

【実施例】以下、本発明の実施例を説明する。図1は本
発明の第1実施例におけるプリント基板の製造工程の一
部を示す図である。この実施例では、ソフトエッチング
後の水洗工程の後にアルカリ洗浄工程を設け、更にその
後に水洗工程を設けている。
Embodiments of the present invention will be described below. FIG. 1 is a diagram showing a part of a manufacturing process of a printed circuit board according to a first embodiment of the present invention. In this embodiment, an alkali washing step is provided after the water washing step after soft etching, and a water washing step is further provided after that.

【0015】アルカリ洗浄で用いられるアルカリ性水溶
液は、この実施例では、水酸化ナトリウム0.005 モル濃
度のものである。このアルカリ性水溶液は例えば洗浄槽
内に満たされ、この場合プリント基板を洗浄槽内のアル
カリ水溶液に浸漬することでアルカリ洗浄が行われる。
The alkaline aqueous solution used in the alkaline washing is, in this example, 0.005 molar sodium hydroxide. This alkaline aqueous solution is filled in, for example, a cleaning tank, and in this case, the alkaline cleaning is performed by immersing the printed circuit board in the alkaline aqueous solution in the cleaning tank.

【0016】アルカリ水溶液によるシャワーによってプ
リント基板のアルカリ洗浄を行ってもよい。この実施例
によると、ソフトエッチング後に銅パターン上に残留し
た硫酸イオンは、アルカリ洗浄時にアルカリと中和反応
して塩となる。このときの反応式を下記する。
The printed circuit board may be washed with an alkali by a shower with an alkaline aqueous solution. According to this embodiment, the sulfate ions remaining on the copper pattern after the soft etching are neutralized with alkali during the alkali cleaning to form a salt. The reaction formula at this time is shown below.

【0017】 2Na+ + SO4 2- → Na2 SO4 このようにして塩が生成されると、この塩は水溶液中で
析出し或いは水溶液に溶解するので、硫酸イオンが銅パ
ターンから消滅して良好な最終表面処理が可能となる。
2Na + + SO 4 2- → Na 2 SO 4 When a salt is thus formed, the salt precipitates in or dissolves in the aqueous solution, so that the sulfate ion disappears from the copper pattern. A good final surface treatment is possible.

【0018】図1の第1実施例では、水洗工程とは別に
アルカリ洗浄工程を設けているが、ソフトエッチング後
の水洗工程で使用される水洗水を水酸化ナトリウム0.00
1 モル濃度水溶液に代えて水洗を行うことによっても、
硫酸イオンを銅パターンから離脱させることができる。
In the first embodiment shown in FIG. 1, an alkali washing step is provided in addition to the water washing step. However, the washing water used in the water washing step after soft etching is 0.003% sodium hydroxide.
By washing with water instead of a 1 molar aqueous solution,
Sulfate ions can be released from the copper pattern.

【0019】この場合、水洗工程で使用される水洗槽の
数が3以上である場合には、最終槽の手前の槽のみをア
ルカリ水洗とし、2槽以下の場合には、アルカリ濃度を
上述の1/2以下として最終槽でアルカリ水洗する。
In this case, when the number of washing tanks used in the washing step is 3 or more, only the tank before the final tank is washed with alkaline water, and in the case of 2 or less tanks, the alkali concentration is the above-mentioned. Rinse with alkaline water in the final tank with a ratio of 1/2 or less.

【0020】図2は本発明の第2実施例におけるプリン
ト基板の製造工程の一部を示す図である。この実施例で
は、水酸化ナトリウム水溶液を用いたアルカリ洗浄に代
えて、アルカリ界面活性剤を用いた洗浄を行っている。
FIG. 2 is a diagram showing a part of the manufacturing process of the printed circuit board in the second embodiment of the present invention. In this example, instead of the alkali cleaning using an aqueous sodium hydroxide solution, cleaning using an alkaline surfactant is performed.

【0021】アルカリ界面活性剤としては例えば家庭用
台所洗剤を用いることができる。その濃度は例えば0.01
重量%に設定される。この場合にも、シャワー或いは浸
漬によってプリント基板が洗浄される。
As the alkaline surfactant, for example, household kitchen detergent can be used. Its concentration is 0.01
Set to weight percent. Also in this case, the printed circuit board is washed by showering or dipping.

【0022】この実施例では、銅パターン上に残留した
硫酸イオンは、アルカリ性界面活性剤溶液での洗浄時に
アルカリと中和反応して塩となり、これを界面活性剤が
ミセル化することで硫酸イオンを銅パターン上から完全
に消滅させることができる。その結果、良好な最終表面
処理を行うことができるようになる。
In this embodiment, the sulfate ion remaining on the copper pattern is neutralized with an alkali during washing with an alkaline surfactant solution to form a salt, and the surfactant is micelle-converted to form a sulfate ion. Can be completely eliminated from the copper pattern. As a result, a good final surface treatment can be performed.

【0023】図3の(A)にアルカリ性界面活性剤の分
子構造を模式的に示す。同図の(B)はその省略記号で
ある。省略記号において右側に位置する黒丸は親水性を
有していることを示している。
FIG. 3A schematically shows the molecular structure of the alkaline surfactant. The symbol (B) in FIG. The black circle on the right side of the ellipsis indicates that it has hydrophilicity.

【0024】図4に界面活性剤によりミセル化された塩
(硫酸ナトリウム)の様子を模式的に示す。Na2 SO
4 分子は、アルカリ性界面活性剤の浸水性を有する部分
が外側になるようにアルカリ性界面活性剤により取り囲
まれ、これが水溶液中に分散されるのである。
FIG. 4 schematically shows a state of a salt (sodium sulfate) which is micellized by a surfactant. Na 2 SO
The four molecules are surrounded by the alkaline surfactant so that the water-immersed portion of the alkaline surfactant is on the outside, and this is dispersed in the aqueous solution.

【0025】従来プロセスに従って表面処理(キレート
系プリフラックス処理)を行い、MIL−STD−20
2E−106Eに規定される温湿度サイクルを3サイク
ル印加した銅パターンと、ソフトエッチング、水洗の
後、家庭用台所洗剤0.01重量%水溶液で浸漬揺動洗浄を
行い、水洗後表面処理(キレート系プリフラックス処
理)して温湿度サイクルを3サイクル印加した銅パター
ンとを比較すると、その表面状態において、従来プロセ
スでは硫酸痕が原因する酸化が認められるが、アルカリ
洗浄を施した銅パターンには酸化の発生が認められなか
った。
Surface treatment (chelate-based pre-flux treatment) was carried out according to the conventional process to obtain MIL-STD-20.
2E-106E copper pattern to which 3 cycles of temperature / humidity cycle are applied, soft etching, washing with water, dipping and rocking washing with 0.01% by weight aqueous solution of household kitchen detergent, and surface treatment after washing with water (chelate pre-treatment). When a copper pattern subjected to a flux treatment) and subjected to a temperature / humidity cycle for 3 cycles is compared, in the surface state, oxidation caused by sulfuric acid traces is recognized in the conventional process, but the copper pattern subjected to alkali cleaning is not No outbreak was observed.

【0026】[0026]

【発明の効果】以上説明したように、本発明によると、
半田付け不良を防止することができるプリント基板の洗
浄方法の提供が可能になるという効果が生じる。
As described above, according to the present invention,
There is an effect that it becomes possible to provide a method of cleaning a printed circuit board that can prevent defective soldering.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明の第1実施例におけるプリント基板の製
造工程の一部を示す図である。
FIG. 1 is a diagram showing part of a process of manufacturing a printed circuit board according to a first embodiment of the present invention.

【図2】本発明の第2実施例におけるプリント基板の製
造工程の一部を示す図である。
FIG. 2 is a diagram showing a part of a manufacturing process of a printed circuit board according to a second embodiment of the present invention.

【図3】アルカリ性界面活性剤の説明図である。FIG. 3 is an explanatory diagram of an alkaline surfactant.

【図4】ミセル構造を示す図である。FIG. 4 is a diagram showing a micelle structure.

【図5】従来方法を示す図である。FIG. 5 is a diagram showing a conventional method.

Claims (2)

【特許請求の範囲】[Claims] 【請求項1】 プリント基板の銅パターンの酸化膜除去
処理を行った後、該プリント基板をアルカリ性水溶液で
洗浄することを特徴とするプリント基板の洗浄方法。
1. A method of cleaning a printed circuit board, which comprises performing an oxide film removal treatment on a copper pattern of the printed circuit board and then cleaning the printed circuit board with an alkaline aqueous solution.
【請求項2】 上記アルカリ性水溶液がアルカリ性界面
活性剤水溶液であることを特徴とする請求項1に記載の
プリント基板の洗浄方法。
2. The method for cleaning a printed circuit board according to claim 1, wherein the alkaline aqueous solution is an alkaline surfactant aqueous solution.
JP17658494A 1994-07-28 1994-07-28 Cleaning of printed board Pending JPH0846333A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP17658494A JPH0846333A (en) 1994-07-28 1994-07-28 Cleaning of printed board

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP17658494A JPH0846333A (en) 1994-07-28 1994-07-28 Cleaning of printed board

Publications (1)

Publication Number Publication Date
JPH0846333A true JPH0846333A (en) 1996-02-16

Family

ID=16016126

Family Applications (1)

Application Number Title Priority Date Filing Date
JP17658494A Pending JPH0846333A (en) 1994-07-28 1994-07-28 Cleaning of printed board

Country Status (1)

Country Link
JP (1) JPH0846333A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007027572A (en) * 2005-07-20 2007-02-01 Sony Corp Semiconductor light emitting device and its manufacturing method
KR100871028B1 (en) * 2007-04-18 2008-11-27 삼성전기주식회사 Process for surface treating printed circuit board

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007027572A (en) * 2005-07-20 2007-02-01 Sony Corp Semiconductor light emitting device and its manufacturing method
KR100871028B1 (en) * 2007-04-18 2008-11-27 삼성전기주식회사 Process for surface treating printed circuit board

Similar Documents

Publication Publication Date Title
JP2675841B2 (en) Electroplating method
US5788830A (en) Electroplating process
JP4445960B2 (en) Method for producing a solution for etching a copper surface and method for depositing a metal on a copper surface
KR100196688B1 (en) Surface treating agents for copper and copper alloy
US20210047734A1 (en) Pretreating liquid for electroless plating to be used during reduction treatment, and process for producing printed wiring board
US20210289637A1 (en) Method for producing printed wiring board
TWI658135B (en) Method of selectively treating copper in the presence of further metal
WO1999031293A1 (en) Pretreating fluid and method of pretreatment for electroless nickel plating
WO2007130282A2 (en) A method and composition for selectively stripping nickel from a substrate
US20200140782A1 (en) Cleaning solution for cleaning metal surfaces
US7063800B2 (en) Methods of cleaning copper surfaces in the manufacture of printed circuit boards
JPH0846333A (en) Cleaning of printed board
JP2812539B2 (en) Reduced family of processes for the manufacture of printed circuits and compositions for performing the processes
JP3226627B2 (en) Copper sulfate plating method for printed wiring boards
JPH06310830A (en) Electroless plating on copper circuit pattern of printed-wiring board
JP2624068B2 (en) Manufacturing method of printed wiring board
JPS59500870A (en) Non-conductive substrate activated catalyst solution and electroless plating method
JPS63129692A (en) Manufacture of printed wiring board
JP2008031536A (en) Direct plating method
JP2737599B2 (en) Electroless plating method on copper circuit pattern of printed wiring board
JPH1030194A (en) Surface treating agent for copper and copper alloy
JPH11135921A (en) Plating method
JPS63206476A (en) Pretreating liquid for electroless copper plating
JPH0469233B2 (en)
CN113766760A (en) Chemical silver plating method for printed circuit board

Legal Events

Date Code Title Description
A02 Decision of refusal

Free format text: JAPANESE INTERMEDIATE CODE: A02

Effective date: 20020326