JP3702278B2

JP3702278B2 - Rotating plating apparatus and electronic component manufacturing method

Info

Publication number: JP3702278B2
Application number: JP2003092059A
Authority: JP
Inventors: 武文吉川; 一郎時澤; 利之山本
Original assignee: Taiyo Chemical Industry Co Ltd
Current assignee: Taiyo Chemical Industry Co Ltd
Priority date: 2003-03-28
Filing date: 2003-03-28
Publication date: 2005-10-05
Anticipated expiration: 2023-03-28
Also published as: JP2004300469A

Description

【０００１】
【発明の属する技術分野】
本発明は、回転メッキ装置とこの回転メッキ装置を利用した電子部品の製造方法に関する。
【０００２】
【従来の技術】
微小な被メッキ物、例えば図２に示すような電子部品用チップＣＣに設けられた下地金属膜ＣＣａ上にニッケル膜や錫膜や銅膜や半田膜等の金属膜を形成する装置として、図１に示すような回転メッキ装置が知られている。
【０００３】
この回転メッキ装置は、メッキ槽１と、メッキ槽１を支持する回転テーブル１１と、回転テーブル１１に連結された回転軸１２と、回転軸１２に接触状態で配置された給電ブラシ１３と、下ケース１４と、下ケース１４上に着脱自在に取り付けられた上ケース１５と、メッキ槽１内に挿入配置された籠状の陽極１６と、メッキ液ＰＬを供給するための給液パイプ１７と、陽極１６内に収容された可溶性金属体１８と、上ケース１５の開口１５ａを塞ぐ蓋板１９とを備える。
【０００４】
メッキ槽１は、円形の支持盤２と、支持盤２上に配置されたリング状の排液部材３と、排液部材３上に配置されたリング状の陰極４と、陰極５上に配置されたリング状のカバー部材５とから構成されている。このメッキ槽１は、支持盤２と排液部材３と陰極４とカバー部材５に形成されたボルト挿通孔（図示省略）に上側からボルト（図示省略）を挿入し、このボルトを回転テーブル１１のボルト穴（図示省略）にねじ込むことによって回転テーブル１１上に着脱自在に取り付けられており、陰極４はこのボルト，支持盤２，回転テーブル１１及び回転軸１２を通じて給電ブラシ１３と導通している。また、カバー部材５の中央には、陽極１６を出し入れするための開口５ａが設けられている。
【０００５】
下ケース１４は回転テーブル１１の周囲及び下側に配置され、上ケース１５の下端部は下ケース１４の上端部に着脱自在に嵌め込まれており、メッキ槽１及び回転テーブル１１は、下ケース１４及び上ケース１５により構成されたケース（符号無し）内に位置している。また、下ケース１４の中央には回転軸１２が遊挿された回転軸挿入孔１４ａが形成され、この回転軸挿入孔１４ａの周囲には環状の貯液部１４ａが形成され、この貯液部１４ａの底面には排液口１４ｃが設けられている。さらに、上ケース１５の中央には陽極１６を出し入れするための開口１５ａが形成され、その側面には窒素ガス等の不活性ガスＩＧをケース内に吹き込むためのガス吹込口１５ｂが形成されている。
【０００６】
この回転メッキ装置を用いて図２に示したチップＣＣの下地膜ＣＣａ上に所定の金属膜、例えばニッケル膜を形成するときには、メッキ槽１内に多数のチップＣＣを投入し、可溶性金属体（ニッケル塊）１８を収納した陽極１６を開口１５ａ，５ａを通じてメッキ槽１内に挿入して開口１５ａを蓋板１９で塞いだ後、給液パイプ１７からメッキ槽１内にメッキ液（ニッケルメッキ用のもの）を供給する。続いて、図示省略のモータからの回転力を変速機等を介して回転軸１２に伝え、回転テーブル１１とその上のメッキ槽１を所定方向に回転させ、チップＣＣを遠心力によって陰極４の内周面に移動させると共に、陽極１６と陰極４の間に所定の電流を流してチップＣＣの下地金属膜ＣＣａ上にニッケル膜を形成する。
【０００７】
メッキ処理時には、所期のメッキ処理が効果的に行えるように、メッキ槽１内のメッキ液ＰＬを排液部材３を通じて外部（上・下ケース１４，１５の内側）に排出し、且つ、排出量に相当するメッキ液ＰＬを給液パイプ１７からメッキ槽１内へ供給してメッキ槽１内の液面高さが一定となるように制御する。また、メッキ処理時には、陰極４の内周面に移動したチップＣＣがメッキ膜によって相互固着することを防止するため、通電を数秒毎に停止すると共にメッキ槽１を逆回転させてチップＣＣの撹拌を行う。
【０００８】
さらに、メッキ処理時には、排液部材３を通じてメッキ槽１から排出されたメッキ液ＰＬを貯液部１４ｂ及び排液口１４ｃを通じてメッキ液槽（図示省略）に戻して再利用するために、上ケース１５のガス吹込口１５ｂからケース内に不活性ガスＩＧを吹き込んでメッキ槽１から排出されたメッキ液ＰＬの酸化を防止する。
【０００９】
【特許文献１】
特開平８−２３９７９９号公報
【特許文献２】
特開平８−２９６０９４号公報
【特許文献３】
特開平１１−１１７０８７号公報
【００１０】
【発明が解決しようとする課題】
メッキ槽１から排出されたメッキ液ＰＬを再利用するためには、排出後のメッキ液ＰＬの酸化を防止してメッキ液ＰＬに含まれる金属イオンの価数の変動（増加）を抑制する必要がある。例えば、メッキ処理により錫膜を形成するときにメッキ槽１から排出されるメッキ液ＰＬに含まれる錫イオンの価数は基本的には２（Ｓｎ²⁺）であるが、このメッキ液ＰＬが酸素を含む空気に触れると価数が４の錫イオン（Ｓｎ⁴⁺）が生成されてしまう。このような４価の錫イオンが含まれるメッキ液ＰＬがメッキ液槽に戻されて再利用されると、次にメッキ処理を行う際の析出効率が低下し、形成される錫膜が空隙の多い低品位のものになって信頼性が格段低下する。
【００１１】
先に述べた従来の回転メッキ装置でも、メッキ処理時には排出メッキ液ＰＬの酸化を防止するためにケース内に不活性ガスＩＧを吹き込むようにしているが、ガス吹込口１５ｂがメッキ槽１の排液部材３の外部露出面よりも高い位置にあるため、メッキ槽１から排出されたメッキ液ＰＬに不活性ガスを効率良く接触させることができない。
【００１２】
要するに、窒素ガス等から成る不活性ガスＩＧは空気よりも比重が軽いため、ガス吹込口１５ｂを通じてケース内に吹き込まれた不活性ガスＩＧはその大半が排出メッキ液ＰＬに接触することなくその上端の開口１５ａと蓋板１９との隙間等から外部に放出されてしまう。また、排液部材３として連通多孔質のものが使用され、しかも、メッキ槽１が高速で回転する関係から、排液部材３から排出されるメッキ液ＰＬは気体と接触し易い霧状或いはこれに近い状態にあるため、排出メッキ液ＰＬは微量の空気と接触するだけで簡単に酸化してしまう。
【００１３】
本発明は前記事情に鑑みて創作されたもので、その目的とするところは、排出メッキ液の酸化を防止できる回転メッキ装置と、この装置を利用した電子部品の製造方法を提供することにある。
【００１４】
【課題を解決するための手段】
前記目的を達成するため、本発明に係る回転メッキ装置は、支持盤とリング状陰極の間にメッキ液排出用の排液部材を備える回転可能なメッキ槽と、メッキ槽内に配置された陽極と、メッキ槽を覆うケースとを具備し、被メッキ物が投入されたメッキ槽を回転させ、且つ、メッキ槽内に供給されたメッキ液を排液部材を通じてメッキ槽外に排出しながら被メッキ物へのメッキ処理を行う回転メッキ装置において、前記ケースには、メッキ槽の排液部材の外部露出面と向き合う位置もしくはそれよりも低い位置に、不活性ガスをケース内に吹き込むためのガス吹込口が設けられている、ことをその特徴とする。
【００１５】
この回転メッキ装置によれば、ガス吹込口がメッキ槽の排液部材の外部露出面と向き合う位置もしくはそれよりも低い位置に設けられているので、メッキ槽から排出されるメッキ液全体に不活性ガスを効果的に接触させてその酸化を防止することができ、酸化による金属イオンの価数変動（増加）を抑制して排出メッキ液の再利用を的確に行うことができる。
【００１６】
また、本発明に係る電子部品の製造方法は、前記の回転メッキ装置を用いて、電子部品用チップに設けられた下地金属膜上に少なくとも１層の金属膜を形成する、ことをその特徴とする。この製造方法によれば、所望の金属膜が適切に形成された電子部品を得ることができる。
【００１７】
本発明の前記目的とそれ以外の目的と、構成特徴と、作用効果は、以下の説明と添付図面によって明らかとなる。
【００１８】
【発明の実施の形態】
［第１実施形態］
図３は本発明に係る回転メッキ装置の第１実施形態を示す。
【００１９】
この回転メッキ装置が、図１に示した従来装置と異なるところは、上ケース１５のガス吹込口１５ｂをメッキ槽１の排液部材２１の外部露出面と向き合う位置よりも低い位置に設けた点と、回転テーブル１１の下面にケース内から回転軸挿入孔１４ａへのメッキ液ＰＬの侵入を抑制する壁部材２２を設けた点と、リング状排液部材３の代わりに円形のシート状排液部材２１を用いた点にある。他の構成は図１に示した従来装置と同じであるので、同一符号を用いその説明を省略する。
【００２０】
ガス吹込口１５ｂはその上端高さ位置が排液部材２１の外部露出面の上端高さ位置よりも低くなるように形成されている。このガス吹込口１５ｂは図示省略のチューブを介してガスボンベ等の不活性ガス供給源に接続されており、窒素ガス等の不活性ガスＩＧが所定の流量で供給される。
【００２１】
壁部材２２は円筒形状を成す部品から成り、下ケース１４の回転軸挿入孔１４ａの近傍位置においてその下端が貯液部１４ｂ内に入り込むように、回転テーブル１１の下面に取り付けられている。この壁部材２２はケース内から回転軸挿入孔１４ａへのメッキ液ＰＬの侵入を抑制するためのもので、壁部材２２の下端は、貯液部１４ｂに一時的に貯留されるメッキ液ＰＬに触れないよう、その下端高さを最大貯液面高さよりも僅かに高く設定されている。
【００２２】
シート状排液部材２１は数μｍ〜数百μｍの空孔を連通状態で有する多孔質のプラスチックやセラミクスや金属焼結体等から成り、円形の支持盤２の表面形状にほぼ合致した形状を有している。また、排液部材２１は、リング状陰極４の下面が接触する外周縁を除く部分の表面によってメッキ槽１の内側底面を構成している。つまり、メッキ槽１内のメッキ液ＰＬは、排液部材２１のリング状陰極接触箇所を除く部分の表面から内部に浸透してその外周面（外部露出面）からメッキ槽１外に排出される。
【００２３】
この回転メッキ装置を用いて微小な被メッキ物、例えば図２に示すような電子部品用チップＣＣの下地金属膜ＣＣａ上に所定の金属膜、例えばニッケル膜を形成するときには、メッキ槽１内に多数のチップＣＣを投入し、可溶性金属体（ニッケル塊）１８を収納した陽極１６を開口１５ａ，５ａを通じてメッキ槽１内に挿入して開口１５ａを蓋板１９で塞いだ後、給液パイプ１７からメッキ槽１内にメッキ液（ニッケルメッキ用のもの）を供給する。続いて、図示省略のモータからの回転力を変速機等を介して回転軸１２に伝え、回転テーブル１１とその上のメッキ槽１を所定方向に回転させ、チップＣＣを遠心力によって陰極４の内周面に移動させると共に、陽極１６と陰極４の間に所定の電流を流してチップＣＣの下地金属膜ＣＣａ上にニッケル膜を形成する。
【００２４】
このメッキ処理時には、所期のメッキ処理が効果的に行えるように、メッキ槽１内のメッキ液ＰＬを排液部材２１を通じて外部（上・下ケース１４，１５の内側）に排出し、且つ、排出量に相当するメッキ液ＰＬを給液パイプ１７からメッキ槽１内へ供給してメッキ槽１内の液面高さが一定となるように制御する。また、メッキ処理時には、陰極４の内周面に移動したチップＣＣがメッキ膜によって相互固着することを防止するため、通電を数秒毎に停止すると共にメッキ槽１を逆回転させてチップＣＣの撹拌を行う。
【００２５】
さらに、メッキ処理時には、排液部材２１を通じてメッキ槽１から排出されたメッキ液ＰＬを貯液部１４ｂ及び排液口１４ｃを通じてメッキ液槽（図示省略）に戻して再利用するために、上ケース１５のガス吹込口１５ｂからケース内に不活性ガスＩＧを吹き込んで、この不活性ガスＩＧによってメッキ槽１から排出されるメッキ液ＰＬの酸化を防止する。
【００２６】
本実施形態では、ガス吹込口１５ｂがその上端高さ位置が排液部材２１の外部露出面の上端高さ位置よりも低くなるように上ケース１５に設けられているので、ガス吹込口１５ｂに送り込まれた不活性ガスＩＧは、図３中に白抜き矢印で示すように、ケース内の排液部材２１の外部露出面のやや下側に向けて吹き込まれると共にここから上方に向かって移動する。
【００２７】
つまり、ケース内に吹き込まれた不活性ガスＩＧは、排液部材２１から排出されるメッキ液ＰＬ全体と効果的に接触することになるので、窒素ガス等から成る不活性ガスＩＧが空気よりも比重が軽くても、不活性ガスＩＧによる排出メッキ液ＰＬの酸化防止を効率良く行って、酸化による金属イオンの価数変動（増加）を抑制することができる。
【００２８】
前記のメッキ処理の前または後にニッケル膜以外の金属膜、例えば銅膜や錫膜や半田膜等を、前記のメッキ処理に先立って或いは前記のメッキ処理後に続けてチップＣＣに形成するときには、メッキ槽１を回転させてメッキ槽１内のメッキ液ＰＬを排液部材２１を通じて排出し、続けて洗浄水を供給しながらメッキ槽１を回転させてメッキ後のチップＣＣの洗浄を行う。洗浄後は、ニッケル塊とは異なる可溶性金属体１８を収納した陽極１６を開口１５ａ，５ａを通じてメッキ槽１内に挿入し、この可溶性金属体１８に対応したメッキ液をメッキ槽１内に供給しながら前記と同様のメッキ処理を行う。
【００２９】
前述の回転メッキ装置によれば、ケース内に吹き込まれた不活性ガスＩＧを排出メッキ液ＰＬ全体と効果的に接触させることができるので、不活性ガスＩＧによる排出メッキ液ＰＬの酸化防止を効率良く行って酸化による金属イオンの価数変動（増加）を抑制し、排出メッキ液ＰＬの再利用を的確に行うことができる。
【００３０】
また、前述の回転メッキ装置によれば、回転テーブル１１の下面にケース内から回転軸挿入孔１４ａへのメッキ液ＰＬの侵入を抑制するための壁部材２２が設けられているので、回転軸１２の軸受部や駆動系にメッキ液ＰＬが回り込むことによる腐食の問題を防止して、これら機器の長寿命化を図ることができる。
【００３１】
さらに、前述の回転メッキ装置によれば、メッキ槽１の排液部材２１が支持盤２の表面形状にほぼ合致した形状のシートから成りメッキ槽１の内側底面を構成しているので、リング状のものに比べ排液有効面積を大きく確保することができ、リング状陰極４の近傍位置でチップＣＣが排液部材２１に付着したとしても排液部材２１を通じてメッキ槽１外に排出されるメッキ液ＰＬの量を十分に確保して所期のメッキ処理を効果的に行うことができる。しかも、排液有効面積が大きく確保されていてメッキ液ＰＬの排出量を十分に確保できることから、メッキ槽１内において下から上に向かう環流の度合が弱く、この環流の影響によってリング状陰極４の内周面に移動したチップＣＣが盛り上がった形態となることを防止して、チップＣＣとリング状陰極４の内周面との最大距離を大きく減少させることができ、これにより、チップＣＣとリング状陰極４の内周面との最大距離の増加を原因とした通電不良の発生を抑制し、メッキ膜厚のバラツキを抑えて品質向上を図ることができる。
【００３２】
尚、前述の実施形態では、ガス吹込口１５ｂとしてその上端が排液部材２１の外部露出面の上端よりも低くなる位置に形成したものを示したが、ガス吹込口１５ｂは、その上端が排液部材２１の外部露出面の下端よりも低くなる位置に形成されていても、排液部材２１の外部露出面と向き合う位置（正対する位置）に形成されていても、前記同様の作用効果を得ることができる。
【００３３】
また、前述の実施形態では、排液部材２１として支持盤２の表面を覆うシート状のものを示したが、図１に示した従来装置と同様のリング状排液部材３を排液部材２１の代わりに用いても構わない。
【００３４】
［第２実施形態］
図４は本発明に係る回転メッキ装置の第２実施形態を示す。
【００３５】
この回転メッキ装置が、図１に示した従来装置と異なるところは、上ケース１５のガス吹込口１５ｂを排除しその代わりに下ケース１４の回転軸挿入孔１４ａの下側にガス吹込口２３ａを有する筒状部品２３を設けた点（回転軸挿入孔１４ａと回転軸１２との隙間をガス吹込口として利用した点）と、回転テーブル１１の下面にケース内から回転軸挿入孔１４ａへのメッキ液ＰＬの侵入を抑制する壁部材２２を設けた点と、リング状排液部材３の代わりに円形のシート状排液部材２１を用いた点にある。他の構成は図１に示した従来装置と同じであるので、同一符号を用いその説明を省略する。
【００３６】
筒状部品２３は回転軸１２の直径よりも僅かに大きな円形孔２３ｂを中央に有し、回転軸挿入孔１４ａと回転軸１２との隙間に通じるガス吹込口２３ａをその側面に有している。このガス吹込口２３ａは図示省略のチューブを介してガスボンベ等の不活性ガス供給源に接続されており、窒素ガス等の不活性ガスＩＧが所定の流量で供給される。
【００３７】
壁部材２２は円筒形状を成す部品から成り、下ケース１４の回転軸挿入孔１４ａの近傍位置においてその下端が貯液部１４ｂ内に入り込むように、回転テーブル１１の下面に取り付けられている。この壁部材２２はケース内から回転軸挿入孔１４ａへのメッキ液ＰＬの侵入を抑制するためのもので、壁部材２２の下端は、貯液部１４ｂに一時的に貯留されるメッキ液ＰＬに触れないよう、その下端高さを最大貯液面高さよりも僅かに高く設定されている。
【００３８】
シート状排液部材２１は数μｍ〜数百μｍの空孔を連通状態で有する多孔質のプラスチックやセラミクスや金属焼結体等から成り、円形の支持盤２の表面形状にほぼ合致した形状を有している。また、排液部材２１は、リング状陰極４の下面が接触する外周縁を除く部分の表面によってメッキ槽１の内側底面を構成している。つまり、メッキ槽１内のメッキ液ＰＬは、排液部材２１のリング状陰極接触箇所を除く部分の表面から内部に浸透してその外周面（外部露出面）からメッキ槽１外に排出される。
【００３９】
この回転メッキ装置を用いて微小な被メッキ物、例えば図２に示すような電子部品用チップＣＣの下地金属膜ＣＣａ上に所定の金属膜、例えばニッケル膜を形成するときには、メッキ槽１内に多数のチップＣＣを投入し、可溶性金属体（ニッケル塊）１８を収納した陽極１６を開口１５ａ，５ａを通じてメッキ槽１内に挿入し開口１５ａを蓋板１９で塞いだ後、給液パイプ１７からメッキ槽１内にメッキ液（ニッケルメッキ用のもの）を供給する。続いて、図示省略のモータからの回転力を変速機等を介して回転軸１２に伝え、回転テーブル１１とその上のメッキ槽１を所定方向に回転させ、チップＣＣを遠心力によって陰極４の内周面に移動させると共に、陽極１６と陰極４の間に所定の電流を流してチップＣＣの下地金属膜ＣＣａ上にニッケル膜を形成する。
【００４０】
このメッキ処理時には、所期のメッキ処理が効果的に行えるように、メッキ槽１内のメッキ液ＰＬを排液部材２１を通じて外部（上・下ケース１４，１５の内側）に排出し、且つ、排出量に相当するメッキ液ＰＬを給液パイプ１７からメッキ槽１内へ供給してメッキ槽１内の液面高さが一定となるように制御する。また、メッキ処理時には、陰極４の内周面に移動したチップＣＣがメッキ膜によって相互固着することを防止するため、通電を数秒毎に停止すると共にメッキ槽１を逆回転させてチップＣＣの撹拌を行う。
【００４１】
さらに、メッキ処理時には、排液部材２１を通じてメッキ槽１から排出されたメッキ液ＰＬを貯液部１４ｂ及び排液口１４ｃを通じてメッキ液槽（図示省略）に戻して再利用するために、下ケース１４の下面に設けた筒状部品２３のガス吹込口２３ａから回転軸挿入孔１４ａと回転軸１２の隙間を通じケース内に不活性ガスＩＧを吹き込んで、この不活性ガスＩＧによってメッキ槽１から排出されるメッキ液ＰＬの酸化を防止する。
【００４２】
本実施形態では、ガス吹込口２３ａが回転軸挿入孔１４ａと回転軸１２の隙間を通じるように下ケース１４の下側に設けられているので、ガス吹込口２３ａから回転軸挿入孔１４ａと回転軸１２との隙間に送り込まれた不活性ガスＩＧは、図４中に白抜き矢印で示すように、回転テーブル１１下面の壁部材２２と貯液部１４ｂの貯留メッキ液ＰＬとの隙間を通じて、ケース内の回転テーブル１４下面側に吹き込まれると共にここから上方に向かって移動する。
【００４３】
つまり、ケース内に吹き込まれた不活性ガスＩＧは、排液部材２１から排出されるメッキ液ＰＬ全体と効果的に接触することになるので、窒素ガス等から成る不活性ガスＩＧが空気よりも比重が軽くても、不活性ガスＩＧによる排出メッキ液ＰＬの酸化防止を効率良く行って、酸化による金属イオンの価数変動（増加）を抑制することができる。
【００４４】
前記のメッキ処理の前または後にニッケル膜以外の金属膜、例えば銅膜や錫膜や半田膜等を、前記のメッキ処理に先立って或いは前記のメッキ処理後に続けてチップＣＣに形成するときには、メッキ槽１を回転させてメッキ槽１内のメッキ液ＰＬを排液部材２１を通じて排出し、続けて洗浄水を供給しながらメッキ槽１を回転させてメッキ後のチップＣＣの洗浄を行う。洗浄後は、ニッケル塊とは異なる可溶性金属体１８を収納した陽極１６を開口１５ａ，５ａを通じてメッキ槽１内に挿入し、この可溶性金属体１８に対応したメッキ液をメッキ槽１内に供給しながら前記と同様のメッキ処理を行う。
【００４５】
前述の回転メッキ装置によれば、ケース内に吹き込まれた不活性ガスＩＧを排出メッキ液ＰＬ全体と効果的に接触させることができるので、不活性ガスＩＧによる排出メッキ液ＰＬの酸化防止を効率良く行って酸化による金属イオンの価数変動（増加）を抑制し、排出メッキ液ＰＬの再利用を的確に行うことができる。
【００４６】
また、前述の回転メッキ装置によれば、回転テーブル１１の下面にケース内から回転軸挿入孔１４ａへのメッキ液ＰＬの侵入を抑制するための壁部材２２が設けられているので、回転軸１２の軸受部や駆動系に排出メッキ液ＰＬが回り込むことによる腐食の問題を防止して、これら機器の長寿命化を図ることができる。しかも、不活性ガスＩＧが、回転軸挿入孔１４ａと回転軸１２との隙間から、回転テーブル１１下面の壁部材２２と貯液部１４ｂの貯留メッキ液ＰＬとの隙間を通じて、ケース内の回転テーブル１４下面側に吹き込まれるので、排出メッキ液ＰＬが回転軸挿入孔１４ａに侵入することを不活性ガスＩＧの圧力により抑制して、回転軸１２の軸受部や駆動系に排出メッキ液ＰＬが回り込むことによる腐食の問題をより確実に防止することができる。
【００４７】
さらに、前述の回転メッキ装置によれば、メッキ槽１の排液部材２１が支持盤２の表面形状にほぼ合致した形状のシートから成りメッキ槽１の内側底面を構成しているので、リング状のものに比べ排液有効面積を大きく確保することができ、リング状陰極４の近傍位置でチップＣＣが排液部材２１に付着したとしても排液部材２１を通じてメッキ槽１外に排出されるメッキ液ＰＬの量を十分に確保して所期のメッキ処理を効果的に行うことができる。しかも、排液有効面積が大きく確保されていてメッキ液ＰＬの排出量を十分に確保できることから、メッキ槽１内において下から上に向かう環流の度合が弱く、この環流の影響によってリング状陰極４の内周面に移動したチップＣＣが盛り上がった形態となることを防止して、チップＣＣとリング状陰極４の内周面との最大距離を大きく減少させることができ、これにより、チップＣＣとリング状陰極４の内周面との最大距離の増加を原因とした通電不良の発生を抑制し、メッキ膜厚のバラツキを抑えて品質向上を図ることができる。
【００４８】
尚、前述の実施形態では、下ケース１４の回転軸挿入孔１４ａの下側にガス吹込口２３ａを有する筒状部品２３を設けたものを示したが、筒状部品２３に相当する部位を下ケース１４に一体形成しても良い。勿論、回転軸挿入孔１４ａと回転軸１２との隙間をガス吹出口として利用できるものであれば筒状部品２３の代わりに他の部品（部位）を用いても良い。
【００４９】
また、前述の実施形態では、排液部材２１として支持盤２の表面を覆うシート状のものを示したが、図１に示した従来装置と同様のリング状排液部材３を排液部材２１の代わりに用いても構わない。
【００５０】
【発明の効果】
以上詳述したように、本発明によれば、排出メッキ液の酸化を防止してその再利用を的確に行える回転メッキ装置を提供できると共に、この装置を用いて所望の金属膜が適切に形成された電子部品を得ることができる。
【図面の簡単な説明】
【図１】従来の回転メッキ装置を示す縦断面図
【図２】電子部品用チップの斜視図
【図３】本発明に係る回転メッキ装置の第１実施形態を示す縦断面図
【図４】本発明に係る回転メッキ装置の第２実施形態を示す縦断面図
【符号の説明】
１…メッキ槽、２…支持盤、４…リング状陰極、５…カバー部材、１１…回転テーブル、１２…回転軸、１３…給電ブラシ、１４…下ケース、１４ａ…回転軸挿入孔、１５…上ケース、１５ｂ…ガス吹込口、１６陽極、１７…給液パイプ、１８…可溶性金属体、１９…蓋板、ＰＬ…メッキ液、ＣＣ…チップ、ＣＣａ…下地金属膜、２１…シート状排液部材、２２…壁部材、２３…筒状部品、２３ａ…ガス吹込口。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotary plating apparatus and an electronic component manufacturing method using the rotary plating apparatus.
[0002]
[Prior art]
As an apparatus for forming a metal film such as a nickel film, a tin film, a copper film, or a solder film on a minute metal substrate, for example, a base metal film CCa provided on an electronic component chip CC as shown in FIG. A rotary plating apparatus as shown in FIG. 1 is known.
[0003]
This rotary plating apparatus includes a plating tank 1, a rotary table 11 that supports the plating tank 1, a rotary shaft 12 connected to the rotary table 11, a power supply brush 13 disposed in contact with the rotary shaft 12, A case 14, an upper case 15 detachably mounted on the lower case 14, a bowl-shaped anode 16 inserted and disposed in the plating tank 1, a liquid supply pipe 17 for supplying the plating liquid PL, A soluble metal body 18 accommodated in the anode 16 and a cover plate 19 that closes the opening 15 a of the upper case 15 are provided.
[0004]
The plating tank 1 is disposed on a circular support plate 2, a ring-shaped drainage member 3 disposed on the support plate 2, a ring-shaped cathode 4 disposed on the drainage member 3, and the cathode 5. It is comprised from the ring-shaped cover member 5 made. In this plating tank 1, bolts (not shown) are inserted from above into bolt insertion holes (not shown) formed in the support plate 2, the drainage member 3, the cathode 4 and the cover member 5, and the bolts are inserted into the rotary table 11. The cathode 4 is detachably mounted on the rotary table 11 by being screwed into a bolt hole (not shown), and the cathode 4 is electrically connected to the power supply brush 13 through the bolt, the support plate 2, the rotary table 11 and the rotary shaft 12. . Further, an opening 5 a for taking in and out the anode 16 is provided in the center of the cover member 5.
[0005]
The lower case 14 is disposed around and below the rotary table 11, and the lower end portion of the upper case 15 is detachably fitted into the upper end portion of the lower case 14. The plating tank 1 and the rotary table 11 include the lower case 14. And it is located in the case (no code | symbol) comprised by the upper case 15. FIG. A rotation shaft insertion hole 14a into which the rotation shaft 12 is loosely inserted is formed at the center of the lower case 14, and an annular liquid storage portion 14a is formed around the rotation shaft insertion hole 14a. A drain port 14c is provided on the bottom surface of 14a. Further, an opening 15a for taking in and out the anode 16 is formed at the center of the upper case 15, and a gas blowing port 15b for blowing an inert gas IG such as nitrogen gas into the case is formed on the side surface. .
[0006]
When a predetermined metal film, for example, a nickel film, is formed on the base film CCa of the chip CC shown in FIG. 2 using this rotary plating apparatus, a large number of chips CC are put into the plating tank 1 and soluble metal bodies ( After the anode 16 containing the nickel lump 18 is inserted into the plating tank 1 through the openings 15a and 5a and the opening 15a is closed with the cover plate 19, a plating solution (for nickel plating) is supplied from the liquid supply pipe 17 into the plating tank 1. Supply). Subsequently, the rotational force from a motor (not shown) is transmitted to the rotary shaft 12 via a transmission or the like, the rotary table 11 and the plating tank 1 thereon are rotated in a predetermined direction, and the chip CC is applied to the cathode 4 by centrifugal force. While moving to the inner peripheral surface, a predetermined current is passed between the anode 16 and the cathode 4 to form a nickel film on the base metal film CCa of the chip CC.
[0007]
During the plating process, the plating solution PL in the plating tank 1 is discharged to the outside (inside the upper and lower cases 14, 15) through the drainage member 3 so that the intended plating process can be effectively performed. The plating liquid PL corresponding to the amount is supplied from the liquid supply pipe 17 into the plating tank 1 to control the liquid level in the plating tank 1 to be constant. Further, during the plating process, in order to prevent the chips CC moved to the inner peripheral surface of the cathode 4 from being adhered to each other by the plating film, the energization is stopped every few seconds and the plating tank 1 is rotated in the reverse direction to agitate the chips CC. I do.
[0008]
Further, at the time of plating, the upper case is used in order to return the plating solution PL discharged from the plating tank 1 through the drainage member 3 to the plating solution tank (not shown) through the liquid storage part 14b and the drainage port 14c for reuse. The inert gas IG is blown into the case from the 15 gas blowing ports 15b to prevent the plating liquid PL discharged from the plating tank 1 from being oxidized.
[0009]
[Patent Document 1]
JP-A-8-239799 [Patent Document 2]
JP-A-8-296094 [Patent Document 3]
Japanese Patent Laid-Open No. 11-117087
[Problems to be solved by the invention]
In order to reuse the plating solution PL discharged from the plating tank 1, it is necessary to prevent the oxidation of the plating solution PL after discharging and suppress the fluctuation (increase) in the valence of metal ions contained in the plating solution PL. There is. For example, the valence of tin ions contained in the plating solution PL discharged from the plating tank 1 when a tin film is formed by plating is basically 2 (Sn ²⁺ ). Touching the air containing oxygen produces tin ions (Sn ⁴⁺ ) having a valence of 4. When the plating solution PL containing such tetravalent tin ions is returned to the plating solution tank and reused, the deposition efficiency during the next plating process is lowered, and the formed tin film has voids. The reliability is greatly reduced due to the low quality.
[0011]
Even in the conventional rotary plating apparatus described above, the inert gas IG is blown into the case in order to prevent oxidation of the discharged plating solution PL during the plating process. Since the liquid member 3 is at a position higher than the externally exposed surface of the liquid member 3, the inert gas cannot be efficiently contacted with the plating liquid PL discharged from the plating tank 1.
[0012]
In short, since the inert gas IG made of nitrogen gas or the like has a lower specific gravity than air, most of the inert gas IG blown into the case through the gas blowing port 15b does not come into contact with the exhaust plating solution PL. Will be discharged to the outside through a gap between the opening 15a and the cover plate 19 or the like. In addition, a communicating porous member is used as the drainage member 3, and the plating solution PL discharged from the drainage member 3 is in the form of a mist that easily comes into contact with gas or the like, because the plating tank 1 rotates at a high speed. Therefore, the exhaust plating solution PL is easily oxidized only by coming into contact with a small amount of air.
[0013]
The present invention was created in view of the above circumstances, and an object of the present invention is to provide a rotary plating apparatus capable of preventing oxidation of discharged plating solution and a method of manufacturing an electronic component using the apparatus. .
[0014]
[Means for Solving the Problems]
In order to achieve the above object, a rotary plating apparatus according to the present invention includes a rotatable plating tank provided with a draining member for discharging a plating liquid between a support plate and a ring-shaped cathode, and an anode disposed in the plating tank. And a case that covers the plating tank, rotates the plating tank in which the object to be plated is charged, and is plated while discharging the plating solution supplied into the plating tank to the outside of the plating tank through the drainage member. In a rotary plating apparatus for performing plating on an object, the case is blown with a gas for blowing an inert gas into the case at a position facing the externally exposed surface of the drainage member of the plating tank or at a position lower than that. The feature is that a mouth is provided.
[0015]
According to this rotary plating apparatus, the gas blowing port is provided at a position facing the externally exposed surface of the drainage member of the plating tank or at a position lower than that, so that the entire plating liquid discharged from the plating tank is inactive. The gas can be effectively contacted to prevent the oxidation thereof, and the valence fluctuation (increase) of metal ions due to the oxidation can be suppressed, so that the exhaust plating solution can be reused accurately.
[0016]
The electronic component manufacturing method according to the present invention is characterized in that at least one metal film is formed on a base metal film provided on an electronic component chip using the rotary plating apparatus. To do. According to this manufacturing method, an electronic component in which a desired metal film is appropriately formed can be obtained.
[0017]
The above object and other objects, structural features, and operational effects of the present invention will become apparent from the following description and the accompanying drawings.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
[First Embodiment]
FIG. 3 shows a first embodiment of a rotary plating apparatus according to the present invention.
[0019]
This rotary plating apparatus is different from the conventional apparatus shown in FIG. 1 in that the gas blowing port 15b of the upper case 15 is provided at a position lower than the position facing the externally exposed surface of the drainage member 21 of the plating tank 1. A wall member 22 that suppresses the penetration of the plating solution PL from the inside of the case into the rotary shaft insertion hole 14a, and a circular sheet-like drainage instead of the ring-like drainage member 3. The member 21 is used. Since the other configuration is the same as that of the conventional apparatus shown in FIG. 1, the same reference numerals are used and description thereof is omitted.
[0020]
The gas blowing port 15b is formed so that its upper end height position is lower than the upper end height position of the externally exposed surface of the drainage member 21. The gas inlet 15b is connected to an inert gas supply source such as a gas cylinder through a tube (not shown), and an inert gas IG such as nitrogen gas is supplied at a predetermined flow rate.
[0021]
The wall member 22 is formed of a cylindrical part, and is attached to the lower surface of the rotary table 11 so that the lower end of the lower member 14 enters the liquid storage part 14b at a position near the rotary shaft insertion hole 14a. The wall member 22 is for suppressing the penetration of the plating solution PL from the inside of the case into the rotary shaft insertion hole 14a, and the lower end of the wall member 22 is the plating solution PL temporarily stored in the liquid storage portion 14b. In order not to touch, the lower end height is set slightly higher than the maximum liquid storage surface height.
[0022]
The sheet-like drainage member 21 is made of porous plastic, ceramics, sintered metal, or the like having pores of several μm to several hundreds of μm in a communicating state, and has a shape that substantially matches the surface shape of the circular support plate 2. Have. Further, the drainage member 21 forms the inner bottom surface of the plating tank 1 by the surface of the portion excluding the outer peripheral edge with which the lower surface of the ring-shaped cathode 4 contacts. In other words, the plating solution PL in the plating tank 1 penetrates into the inside from the surface of the drainage member 21 excluding the ring-shaped cathode contact portion, and is discharged from the outer peripheral surface (externally exposed surface) to the outside of the plating tank 1. .
[0023]
When a predetermined metal film, such as a nickel film, is formed on the base metal film CCa of the electronic component chip CC as shown in FIG. A large number of chips CC are inserted, the anode 16 containing the soluble metal body (nickel lump) 18 is inserted into the plating tank 1 through the openings 15a and 5a, and the opening 15a is closed with the cover plate 19, and then the liquid supply pipe 17 is inserted. Then, a plating solution (for nickel plating) is supplied into the plating tank 1. Subsequently, the rotational force from a motor (not shown) is transmitted to the rotary shaft 12 via a transmission or the like, the rotary table 11 and the plating tank 1 thereon are rotated in a predetermined direction, and the chip CC is applied to the cathode 4 by centrifugal force. While moving to the inner peripheral surface, a predetermined current is passed between the anode 16 and the cathode 4 to form a nickel film on the base metal film CCa of the chip CC.
[0024]
During the plating process, the plating solution PL in the plating tank 1 is discharged to the outside (inside the upper and lower cases 14 and 15) through the drainage member 21 so that the intended plating process can be effectively performed, and The plating liquid PL corresponding to the discharged amount is supplied from the liquid supply pipe 17 into the plating tank 1 and controlled so that the liquid level in the plating tank 1 is constant. Further, during the plating process, in order to prevent the chips CC moved to the inner peripheral surface of the cathode 4 from being adhered to each other by the plating film, the energization is stopped every few seconds and the plating tank 1 is rotated in the reverse direction to agitate the chips CC. I do.
[0025]
Further, in the plating process, the upper case is used to reuse the plating solution PL discharged from the plating tank 1 through the drainage member 21 by returning it to the plating solution tank (not shown) through the liquid storage part 14b and the drainage port 14c. The inert gas IG is blown into the case from the 15 gas blowing ports 15b, and the oxidation of the plating solution PL discharged from the plating tank 1 is prevented by the inert gas IG.
[0026]
In the present embodiment, the gas blowing port 15b is provided in the upper case 15 so that the upper end height position thereof is lower than the upper end height position of the externally exposed surface of the drainage member 21, so that the gas blowing port 15b The inert gas IG sent in is blown toward the lower side of the externally exposed surface of the drainage member 21 in the case and moves upward from here, as indicated by the white arrow in FIG. .
[0027]
That is, since the inert gas IG blown into the case effectively comes into contact with the entire plating solution PL discharged from the drainage member 21, the inert gas IG made of nitrogen gas or the like is more than air. Even if the specific gravity is light, it is possible to efficiently prevent oxidation of the exhaust plating solution PL by the inert gas IG, and to suppress valence fluctuation (increase) of metal ions due to oxidation.
[0028]
When a metal film other than a nickel film, such as a copper film, a tin film, or a solder film, is formed on the chip CC before or after the plating process before or after the plating process, plating is performed. The tank 1 is rotated to discharge the plating solution PL in the plating tank 1 through the drainage member 21, and the plating tank 1 is rotated while supplying the cleaning water to clean the chip CC after plating. After cleaning, the anode 16 containing the soluble metal body 18 different from the nickel block is inserted into the plating tank 1 through the openings 15a and 5a, and the plating solution corresponding to the soluble metal body 18 is supplied into the plating tank 1. However, the same plating treatment as described above is performed.
[0029]
According to the rotary plating apparatus described above, the inert gas IG blown into the case can be effectively brought into contact with the entire exhaust plating solution PL, so that the exhaust plating solution PL is effectively prevented from being oxidized by the inert gas IG. It can be performed well to suppress valence fluctuation (increase) of metal ions due to oxidation, and the exhaust plating solution PL can be reused accurately.
[0030]
Further, according to the above-described rotary plating apparatus, the wall member 22 is provided on the lower surface of the rotary table 11 to suppress the penetration of the plating solution PL from the case into the rotary shaft insertion hole 14a. This prevents the problem of corrosion caused by the plating solution PL flowing around the bearing portion and the drive system of the motor, thereby extending the life of these devices.
[0031]
Further, according to the above-described rotary plating apparatus, the drainage member 21 of the plating tank 1 is made of a sheet having a shape substantially matching the surface shape of the support plate 2 and constitutes the inner bottom surface of the plating tank 1. The effective drainage area can be ensured larger than that of the above-described one, and even if the chip CC adheres to the drainage member 21 in the vicinity of the ring-shaped cathode 4, the plating discharged to the outside of the plating tank 1 through the drainage member 21. A sufficient amount of the liquid PL can be secured to effectively perform the intended plating process. Moreover, since a large effective drainage area is ensured and the discharge amount of the plating solution PL can be sufficiently secured, the degree of recirculation from the bottom to the top in the plating tank 1 is weak, and the ring-like cathode 4 is affected by this recirculation. It is possible to prevent the chip CC moved to the inner peripheral surface from becoming a raised form, and to greatly reduce the maximum distance between the chip CC and the inner peripheral surface of the ring-shaped cathode 4. It is possible to improve the quality by suppressing the occurrence of energization failure due to an increase in the maximum distance from the inner peripheral surface of the ring-shaped cathode 4 and suppressing variations in the plating film thickness.
[0032]
In the above-described embodiment, the gas blowing port 15b is formed at a position where the upper end is lower than the upper end of the externally exposed surface of the drainage member 21, but the upper end of the gas blowing port 15b is drained. Even if the liquid member 21 is formed at a position lower than the lower end of the externally exposed surface of the liquid member 21 or is formed at a position facing the externally exposed surface of the drainage member 21 (a position facing directly), the same effect as described above can be obtained. Obtainable.
[0033]
In the above-described embodiment, a sheet-like member covering the surface of the support plate 2 is shown as the drainage member 21. However, the ring-shaped drainage member 3 similar to the conventional apparatus shown in FIG. It may be used instead of.
[0034]
[Second Embodiment]
FIG. 4 shows a second embodiment of the rotary plating apparatus according to the present invention.
[0035]
This rotary plating apparatus is different from the conventional apparatus shown in FIG. 1 in that the gas blowing port 15b of the upper case 15 is excluded and a gas blowing port 23a is provided below the rotating shaft insertion hole 14a of the lower case 14 instead. The point which provided the cylindrical component 23 which has (the point which utilized the clearance gap between the rotating shaft insertion hole 14a and the rotating shaft 12 as a gas blowing port), and the plating to the rotating shaft insertion hole 14a from the inside of a case on the lower surface of the rotating table 11 The wall member 22 that suppresses the penetration of the liquid PL is provided, and the circular sheet-like drainage member 21 is used instead of the ring-like drainage member 3. Since the other configuration is the same as that of the conventional apparatus shown in FIG. 1, the same reference numerals are used and description thereof is omitted.
[0036]
The cylindrical part 23 has a circular hole 23b that is slightly larger than the diameter of the rotating shaft 12 in the center, and a gas blowing port 23a that communicates with the gap between the rotating shaft insertion hole 14a and the rotating shaft 12 on its side surface. . The gas inlet 23a is connected to an inert gas supply source such as a gas cylinder through a tube (not shown), and an inert gas IG such as nitrogen gas is supplied at a predetermined flow rate.
[0037]
The wall member 22 is formed of a cylindrical part, and is attached to the lower surface of the rotary table 11 so that the lower end of the lower member 14 enters the liquid storage part 14b at a position near the rotary shaft insertion hole 14a. The wall member 22 is for suppressing the penetration of the plating solution PL from the inside of the case into the rotary shaft insertion hole 14a, and the lower end of the wall member 22 is the plating solution PL temporarily stored in the liquid storage portion 14b. In order not to touch, the lower end height is set slightly higher than the maximum liquid storage surface height.
[0038]
The sheet-like drainage member 21 is made of porous plastic, ceramics, sintered metal, or the like having pores of several μm to several hundreds of μm in a communicating state, and has a shape that substantially matches the surface shape of the circular support plate 2. Have. Further, the drainage member 21 forms the inner bottom surface of the plating tank 1 by the surface of the portion excluding the outer peripheral edge with which the lower surface of the ring-shaped cathode 4 contacts. In other words, the plating solution PL in the plating tank 1 penetrates into the inside from the surface of the drainage member 21 excluding the ring-shaped cathode contact portion, and is discharged from the outer peripheral surface (externally exposed surface) to the outside of the plating tank 1. .
[0039]
When a predetermined metal film, such as a nickel film, is formed on the base metal film CCa of the electronic component chip CC as shown in FIG. After inserting a large number of chips CC and inserting the anode 16 containing the soluble metal body (nickel lump) 18 into the plating tank 1 through the openings 15a and 5a and closing the opening 15a with the cover plate 19, the liquid supply pipe 17 A plating solution (for nickel plating) is supplied into the plating tank 1. Subsequently, the rotational force from a motor (not shown) is transmitted to the rotary shaft 12 via a transmission or the like, the rotary table 11 and the plating tank 1 thereon are rotated in a predetermined direction, and the chip CC is applied to the cathode 4 by centrifugal force. While moving to the inner peripheral surface, a predetermined current is passed between the anode 16 and the cathode 4 to form a nickel film on the base metal film CCa of the chip CC.
[0040]
During the plating process, the plating solution PL in the plating tank 1 is discharged to the outside (inside the upper and lower cases 14 and 15) through the drainage member 21 so that the intended plating process can be effectively performed, and The plating liquid PL corresponding to the discharged amount is supplied from the liquid supply pipe 17 into the plating tank 1 and controlled so that the liquid level in the plating tank 1 is constant. Further, during the plating process, in order to prevent the chips CC moved to the inner peripheral surface of the cathode 4 from being adhered to each other by the plating film, the energization is stopped every few seconds and the plating tank 1 is rotated in the reverse direction to agitate the chips CC. I do.
[0041]
Further, at the time of plating, the lower case is used in order to return the plating solution PL discharged from the plating tank 1 through the drainage member 21 to the plating solution tank (not shown) through the liquid storage part 14b and the drainage port 14c for reuse. The inert gas IG is blown into the case through the gap between the rotary shaft insertion hole 14a and the rotary shaft 12 from the gas blowing port 23a of the cylindrical component 23 provided on the lower surface of the cylindrical part 23, and is discharged from the plating tank 1 by this inert gas IG. This prevents oxidation of the plating solution PL.
[0042]
In the present embodiment, since the gas blowing port 23a is provided on the lower side of the lower case 14 so as to pass through the gap between the rotating shaft insertion hole 14a and the rotating shaft 12, the gas blowing port 23a rotates with the rotating shaft insertion hole 14a. The inert gas IG fed into the gap with the shaft 12 passes through the gap between the wall member 22 on the lower surface of the turntable 11 and the stored plating solution PL of the liquid storage portion 14b, as indicated by the white arrow in FIG. It is blown to the lower surface side of the rotary table 14 in the case and moves upward from here.
[0043]
That is, since the inert gas IG blown into the case effectively comes into contact with the entire plating solution PL discharged from the drainage member 21, the inert gas IG made of nitrogen gas or the like is more than air. Even if the specific gravity is light, it is possible to efficiently prevent oxidation of the exhaust plating solution PL by the inert gas IG, and to suppress valence fluctuation (increase) of metal ions due to oxidation.
[0044]
When a metal film other than a nickel film, such as a copper film, a tin film, or a solder film, is formed on the chip CC before or after the plating process before or after the plating process, plating is performed. The tank 1 is rotated to discharge the plating solution PL in the plating tank 1 through the drainage member 21, and the plating tank 1 is rotated while supplying the cleaning water to clean the chip CC after plating. After cleaning, the anode 16 containing the soluble metal body 18 different from the nickel block is inserted into the plating tank 1 through the openings 15a and 5a, and the plating solution corresponding to the soluble metal body 18 is supplied into the plating tank 1. However, the same plating treatment as described above is performed.
[0045]
According to the rotary plating apparatus described above, the inert gas IG blown into the case can be effectively brought into contact with the entire exhaust plating solution PL, so that the exhaust plating solution PL is effectively prevented from being oxidized by the inert gas IG. It can be performed well to suppress valence fluctuation (increase) of metal ions due to oxidation, and the exhaust plating solution PL can be reused accurately.
[0046]
Further, according to the above-described rotary plating apparatus, the wall member 22 is provided on the lower surface of the rotary table 11 to suppress the penetration of the plating solution PL from the case into the rotary shaft insertion hole 14a. This prevents the problem of corrosion caused by the exhaust plating solution PL flowing around the bearing portion and the drive system of the motor, thereby extending the life of these devices. Moreover, the inert gas IG passes through the gap between the rotary shaft insertion hole 14a and the rotary shaft 12 through the gap between the wall member 22 on the lower surface of the rotary table 11 and the stored plating solution PL in the liquid storage portion 14b. 14 is blown into the lower surface side, so that the exhaust plating solution PL is prevented from entering the rotary shaft insertion hole 14a by the pressure of the inert gas IG, and the exhaust plating solution PL wraps around the bearing portion and the drive system of the rotary shaft 12. Corrosion problems caused by this can be prevented more reliably.
[0047]
Further, according to the above-described rotary plating apparatus, the drainage member 21 of the plating tank 1 is made of a sheet having a shape substantially matching the surface shape of the support plate 2 and constitutes the inner bottom surface of the plating tank 1. The effective drainage area can be ensured larger than that of the above-described one, and even if the chip CC adheres to the drainage member 21 in the vicinity of the ring-shaped cathode 4, the plating discharged to the outside of the plating tank 1 through the drainage member 21. A sufficient amount of the liquid PL can be secured to effectively perform the intended plating process. In addition, since the effective drainage area is large and the discharge amount of the plating solution PL can be sufficiently secured, the degree of recirculation from the bottom to the top in the plating tank 1 is weak. It is possible to prevent the chip CC moved to the inner peripheral surface from becoming a raised form, and to greatly reduce the maximum distance between the chip CC and the inner peripheral surface of the ring-shaped cathode 4. It is possible to improve the quality by suppressing the occurrence of energization failure due to an increase in the maximum distance from the inner peripheral surface of the ring-shaped cathode 4 and suppressing variations in the plating film thickness.
[0048]
In the above-described embodiment, the cylindrical part 23 having the gas blowing port 23a is provided below the rotating shaft insertion hole 14a of the lower case 14, but the portion corresponding to the cylindrical part 23 is located below. It may be formed integrally with the case 14. Of course, other parts (parts) may be used instead of the cylindrical part 23 as long as the gap between the rotary shaft insertion hole 14a and the rotary shaft 12 can be used as a gas outlet.
[0049]
In the above-described embodiment, a sheet-like member covering the surface of the support plate 2 is shown as the drainage member 21. However, the ring-shaped drainage member 3 similar to the conventional apparatus shown in FIG. It may be used instead of.
[0050]
【The invention's effect】
As described above in detail, according to the present invention, it is possible to provide a rotary plating apparatus that can prevent the exhausted plating solution from being oxidized and reuse it accurately, and to form a desired metal film appropriately using this apparatus. Can be obtained.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a conventional rotary plating apparatus. FIG. 2 is a perspective view of a chip for an electronic component. FIG. 3 is a longitudinal sectional view showing a first embodiment of a rotary plating apparatus according to the invention. FIG. 4 is a longitudinal sectional view showing a second embodiment of the rotary plating apparatus according to the present invention.
DESCRIPTION OF SYMBOLS 1 ... Plating tank, 2 ... Supporting plate, 4 ... Ring-shaped cathode, 5 ... Cover member, 11 ... Rotary table, 12 ... Rotary shaft, 13 ... Feeding brush, 14 ... Lower case, 14a ... Rotary shaft insertion hole, 15 ... Upper case, 15b ... Gas inlet, 16 anode, 17 ... Supply pipe, 18 ... Soluble metal body, 19 ... Lid plate, PL ... Plating solution, CC ... Chip, CCa ... Base metal film, 21 ... Sheet drainage Member, 22 ... Wall member, 23 ... Cylindrical part, 23a ... Gas inlet.

Claims

A rotatable plating tank provided with a drainage member for discharging a plating solution between the support plate and the ring-shaped cathode, an anode disposed in the plating tank, and a case covering the plating tank, In the rotary plating apparatus that rotates the charged plating tank and performs the plating process on the object to be plated while discharging the plating solution supplied into the plating tank to the outside of the plating tank through the drainage member,
The case is provided with a gas blowing port for blowing an inert gas into the case at a position facing the externally exposed surface of the drainage member of the plating tank or at a position lower than that.
A rotary plating apparatus characterized by that.

A rotary table that supports the plating tank; and a rotary shaft connected to the rotary table. The case has a rotary shaft insertion hole at a lower portion thereof to cover the plating tank and the rotary table. On the lower surface, a wall member is provided to suppress the penetration of the plating solution from the case into the rotary shaft insertion hole,
The rotary plating apparatus according to claim 1.

A rotary table for supporting the plating tank and a rotary shaft connected to the rotary table, the case has a rotary shaft insertion hole in the lower part thereof and has a form for covering the plating tank and the rotary table, and a gas blowing port Is constituted by a gap between the rotary shaft insertion hole and the rotary shaft,
The rotary plating apparatus according to claim 1.

A wall member is provided on the lower surface of the rotary table to suppress the penetration of the plating solution from the case into the rotary shaft insertion hole.
The rotary plating apparatus according to claim 3.

Using the rotary plating apparatus according to any one of claims 1 to 4, at least one metal film is formed on a base metal film provided on an electronic component chip.
An electronic component manufacturing method characterized by the above.