JPH05331679A - Plating device - Google Patents
Plating deviceInfo
- Publication number
- JPH05331679A JPH05331679A JP16703192A JP16703192A JPH05331679A JP H05331679 A JPH05331679 A JP H05331679A JP 16703192 A JP16703192 A JP 16703192A JP 16703192 A JP16703192 A JP 16703192A JP H05331679 A JPH05331679 A JP H05331679A
- Authority
- JP
- Japan
- Prior art keywords
- plating
- plated
- film
- nozzle
- plating solution
- 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
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- Electroplating Methods And Accessories (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明はめっき装置に関し、より
詳細には電子部品等の微細なパターンに電気めっきを行
うめっき装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plating apparatus, and more particularly to a plating apparatus for electroplating a fine pattern of an electronic component or the like.
【０００２】[0002]
【従来の技術】近年めっき被膜は、装飾，防蝕用に限ら
ず機能性被膜として電子部品等に幅広く使用されてい
る。例えば電子部品を装着する各種プリント基板の配線
には銅めっき，金めっきが用いられている。また高い記
録密度を有するコンピュータ用ハードディスクに使用さ
れる薄膜磁気ヘッドの磁極（ポール）には、磁性体めっ
き法によるパーマロイ薄膜が用いられ、薄膜磁気ヘッド
のコイルや配線には銅めっきによる薄膜も用いられてい
る。2. Description of the Related Art In recent years, a plating film has been widely used as a functional film not only for decoration and anticorrosion, but also for electronic parts. For example, copper plating and gold plating are used for wiring of various printed circuit boards on which electronic components are mounted. Permalloy thin films formed by magnetic plating are used for the magnetic poles of thin film magnetic heads used in hard disks for computers with high recording density, and thin films formed by copper plating are also used for coils and wiring of thin film magnetic heads. Has been.
【０００３】薄膜磁気ヘッドの磁極はめっき膜のもつ電
気的，磁性的特性を利用するため組成，膜厚，膜質など
の均一なめっき膜が要求される。しかし、薄膜磁気ヘッ
ドは薄膜を積み重ねて作製されるため狭い面積にこのパ
ターニングによる数ミクロンから数十ミクロン程度の段
差があり、めっきした場合のめっき膜の組成，膜厚，膜
質などが均一にならない。Since the magnetic poles of the thin film magnetic head utilize the electrical and magnetic characteristics of the plated film, a uniform plated film of composition, film thickness and film quality is required. However, the thin-film magnetic head is manufactured by stacking thin films, so there is a step of several microns to several tens of microns due to this patterning in a small area, and the plating film composition, film thickness, and film quality are not uniform when plated. ..
【０００４】特に薄膜磁気ヘッドの磁極等に用いるNi−
Fe合金のめっきは、異常共析型に属し、Niに比べてFeが
析出し易く、めっき条件の変動に対して敏感に組成が変
動する。めっき条件の中でも特に重要とされることは、
再現性よくウエハ表面上に均一な流れを作ることであ
る。米国特許4102756 号はパドル式往復運動撹拌めっき
装置を開示しており、この装置は、パドルの往復運動に
より陰極面の上に均一な流れを生じさせようとするもの
であるが、全めっきサイクルにおける流路全体にわたる
層状の流れを発生し得ない。Ni-, which is particularly used for magnetic poles of thin-film magnetic heads, etc.
The plating of Fe alloy belongs to the abnormal eutectoid type, in which Fe is more likely to precipitate than Ni, and the composition fluctuates sensitively to changes in plating conditions. Among the plating conditions, what is particularly important is
The goal is to create a uniform flow over the wafer surface with good reproducibility. U.S. Pat.No. 4,102,756 discloses a paddle reciprocating stir plating apparatus which attempts to create a uniform flow over the cathode surface by the reciprocating movement of the paddle, but in all plating cycles. Laminar flow over the entire flow path cannot occur.
【０００５】特開昭62-207895 号はめっき液に層状の流
れを与えるために、固定された２つの壁材によって流路
を限定し、その流路に下方から上方に向けてめっき液が
オーバーフローするようにしためっき装置を開示してい
る。また特開平2-225693号ではカップ式噴流めっき装置
においてウエハの中心部と外周部でのめっき厚のバラツ
キをなくすためにめっき液入口上部に整流器を配置して
めっき液の流れを制御するめっき装置が開示されてい
る。JP-A-62-207895 discloses that a flow path is limited by two fixed wall members in order to give a laminar flow to the plating solution, and the plating solution overflows from the bottom to the top of the flow path. There is disclosed a plating apparatus configured to do so. Further, in Japanese Patent Laid-Open No. 2-225693, in a cup-type jet plating device, a rectifier is disposed above the plating solution inlet to control the flow of the plating solution in order to eliminate variations in the plating thickness between the central portion and the outer peripheral portion of the wafer. Is disclosed.
【０００６】[0006]
【発明が解決しようとする課題】めっき条件に敏感に反
応する異常共析系のめっきを精密に行う場合、上記のい
ずれの装置においても微小で且つ凹凸のある場所に完全
に一様な流れを分布させることは困難である。図５(a)
は薄膜磁気ヘッドの模式的平面図、図５(b) はその一部
のＩ−Ｉ線における模式的縦断面図である。図中21,22
は磁気コアの上磁極（上ポール），下磁極（下ポール）
を示し、一般に磁気コアはフレームめっきと呼ばれる方
法によって作製される (米国特許3853715 号) 。図中2
4,25,26は磁気コアの先端部、中心部、後端部を示して
おり、上磁極（上ポール）21の場合は先端部24や後端部
26に段差を有する表面にめっきを行わなければならな
い。米国特許4102756 号に開示されているパドルを備え
ためっき行った場合、図６の○で示す如く先端部24及び
後端部26において鉄組成が変化している。これは段差の
上，下でめっき液の流れが異なり、めっき条件が均一に
保てないことが原因である。When carrying out precise plating of an abnormal eutectoid system which reacts sensitively to plating conditions, in any of the above-mentioned devices, a perfectly uniform flow is applied to a minute and uneven place. It is difficult to distribute. Figure 5 (a)
Is a schematic plan view of the thin film magnetic head, and FIG. 5 (b) is a schematic longitudinal sectional view of a part thereof taken along line I-I. 21,22 in the figure
Is the magnetic pole upper pole (upper pole), lower pole (lower pole)
The magnetic core is generally manufactured by a method called frame plating (US Patent No. 3853715). 2 in the figure
4,25,26 indicate the front end, the center, and the rear end of the magnetic core. In the case of the upper magnetic pole (upper pole) 21, the front end 24 and the rear end.
The stepped surface of 26 must be plated. When the plating with the paddle disclosed in U.S. Pat. No. 4,102,756 is performed, the iron composition changes at the leading end portion 24 and the trailing end portion 26 as indicated by the circles in FIG. This is because the flow of the plating solution is different above and below the step, and the plating conditions cannot be kept uniform.
【０００７】そこでめっき液の流れを均一にするためパ
ドル速度を上げて更にめっき液を撹拌してめっきを行っ
た。その場合の鉄組成を図６の×で示す。図６から明ら
かな如く先端部24における鉄組成のバラツキは改善され
るが、後端部26のくぼみ23においては依然として改善さ
れていない。このように従来のめっき装置を用いて撹拌
効果を上げるだけでは均一なめっき膜を得ることは困難
である。Therefore, in order to make the flow of the plating solution uniform, the paddle speed was increased to further stir the plating solution for plating. The iron composition in that case is shown by x in FIG. As is clear from FIG. 6, the variation in the iron composition at the front end portion 24 is improved, but it is not yet improved at the recess 23 at the rear end portion 26. As described above, it is difficult to obtain a uniform plating film only by improving the stirring effect using the conventional plating apparatus.
【０００８】本発明は斯かる事情に鑑みてなされたもの
であり、薄膜磁気ヘッドのような微小な領域で数十ミク
ロン程度の段差をもつ被めっき物に対してもめっき膜の
組成を均一にすることが可能なめっき装置を提供するこ
とを目的とする。The present invention has been made in view of such circumstances, and makes the composition of a plating film uniform even for an object to be plated having a step of about several tens of microns in a minute region such as a thin film magnetic head. It is an object of the present invention to provide a plating apparatus that can be used.
【０００９】[0009]
【課題を解決するための手段】本発明に係るめっき装置
は、めっき層内のめっき液を撹拌して、被めっき物の被
めっき面上にめっき液の流れを形成すべくなしためっき
装置において、被めっき物の被めっき面に対してめっき
液の撹拌と同時的にめっき液を吹きつける手段を備えた
ことを特徴とする。A plating apparatus according to the present invention is a plating apparatus for stirring a plating solution in a plating layer to form a flow of the plating solution on a surface to be plated of an object to be plated. A means for spraying the plating solution simultaneously with stirring the plating solution onto the surface to be plated of the object to be plated is provided.
【００１０】[0010]
【作用】本発明に係るめっき装置は被めっき物の被めっ
き面に対してめっき液の撹拌と同時的に別途めっき液を
吹きつけて強制的にめっき液を供給することにより段差
を有する表面、例えば井戸状のくぼみを有する微細な表
面上にも均一な流れを与えることができる。The plating apparatus according to the present invention has a stepped surface by spraying a separate plating solution onto the surface of the object to be plated at the same time as stirring the plating solution and forcibly supplying the plating solution. For example, a uniform flow can be provided even on a fine surface having well-shaped depressions.
【００１１】[0011]
【実施例】以下本発明をその実施例を示す図面に基づき
具体的に説明する。図１(a) は本発明に係る実施例のめ
っき装置の模式的縦断面図であり、図中１はアクリル樹
脂でつくられた角型のめっき槽である。このめっき槽１
には電気めっきを行うためのカソード３が下部に、アノ
ード４が上部に配置されており、被めっき物であるウエ
ハ10はカソード３に装着される。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the drawings showing the embodiments. FIG. 1 (a) is a schematic vertical cross-sectional view of a plating apparatus of an embodiment according to the present invention, in which 1 is a rectangular plating tank made of acrylic resin. This plating tank 1
The cathode 3 for electroplating is arranged in the lower part and the anode 4 is arranged in the upper part, and the wafer 10, which is the object to be plated, is mounted on the cathode 3.
【００１２】めっき液14は調整槽13においてpH濃度を調
整され、ペルティエ素子を用いた電子恒温装置８で温度
を制御され、ポンプ12a をへて流量調整バルブ11a で流
量を調整されてめっき槽１に送られ、オーバーフローし
ためっき液14は回収されて調整槽13に戻る。めっき液14
を撹拌する手段及び吹きつける手段としてめっき槽１内
の上方よりめっき槽１内へ向けてノズル２が垂設されて
おり、アノード４とカソード３の間に相当するノズル２
内の位置に上，下パドル６，７が配設されており、下パ
ドル７には後述するノズル穴27があいている。めっき液
14は調整槽13より電子恒温装置８とポンプ12b をへて、
調整バルブ11b によって流量調整されてノズル２に送ら
れる。図１(b) は図１(a) に示すめっき装置の平面図で
ある。ノズル２は連結棒15及びクランク16を介してモー
タ５に連結されており、いわゆるピストン・クランク機
構を呈し往復運動するようになっている。The pH of the plating solution 14 is adjusted in the adjusting tank 13, the temperature is controlled by the electronic thermostat 8 using the Peltier element, and the flow rate is adjusted by the flow rate adjusting valve 11a through the pump 12a. And the overflowed plating solution 14 is recovered and returned to the adjusting tank 13. Plating solution 14
A nozzle 2 is vertically provided from above in the plating tank 1 toward the inside of the plating tank 1 as a means for agitating and spraying the same, and a nozzle 2 corresponding to between the anode 4 and the cathode 3 is provided.
Upper and lower paddles 6 and 7 are provided at the inner positions, and a nozzle hole 27 described later is formed in the lower paddle 7. Plating solution
14 is a thermostat 8 and a pump 12b from the adjusting tank 13,
The flow rate is adjusted by the adjusting valve 11b and sent to the nozzle 2. FIG. 1 (b) is a plan view of the plating apparatus shown in FIG. 1 (a). The nozzle 2 is connected to the motor 5 via a connecting rod 15 and a crank 16, and has a so-called piston-crank mechanism to reciprocate.
【００１３】図２はノズル２の模式的縦断面図である。
ノズル２の支柱29は上，下パドル６，７を両側から支持
しており、めっき液14は管30を通って下パドル７に送ら
れる。下パドル７は中空になっており、その空洞にはめ
っき液14の圧力調整用に直径５mmのガラス玉28が入れて
ある。ウエハ10に対向する下パドル７の底面にはめっき
液14を噴出するためのノズル穴27があけてある。図３は
ノズル穴27の配置を示す下パドル７の底面図である。ノ
ズル２から供給されるめっき液14がウエハ10全面に均一
に供給されるように、ノズル穴27をなるべく小さく、且
つ密にし、また互い違いに配列されている。具体的には
直径１mmのノズル穴22が2.5mm 間隔で10列互い違いに配
置してある。FIG. 2 is a schematic vertical sectional view of the nozzle 2.
The column 29 of the nozzle 2 supports the upper and lower paddles 6 and 7 from both sides, and the plating solution 14 is sent to the lower paddle 7 through the pipe 30. The lower paddle 7 is hollow, and a glass ball 28 having a diameter of 5 mm is placed in the hollow for adjusting the pressure of the plating solution 14. A nozzle hole 27 for ejecting the plating solution 14 is formed on the bottom surface of the lower paddle 7 facing the wafer 10. FIG. 3 is a bottom view of the lower paddle 7 showing the arrangement of the nozzle holes 27. The nozzle holes 27 are made as small and dense as possible so that the plating solution 14 supplied from the nozzles 2 is uniformly supplied to the entire surface of the wafer 10, and the nozzle holes 27 are staggered. Specifically, nozzle holes 22 having a diameter of 1 mm are arranged alternately in 10 rows at 2.5 mm intervals.
【００１４】以上の如く構成された装置を使用してパー
マロイ合金のめっきを行う実施例を具体的に数値と共に
説明する。カソード3 にセットされたウエハ10には予め
パーマロイ合金膜が下地としてスパッタ法により成膜さ
れている。アノード４は２mm厚の含硫黄Ni金属板を用い
る。めっき液14には金属イオンとしてNiCl2 ・６Ｈ2Ｏ
を60g/l 、FeSO4 ・７Ｈ2 Ｏを1.5g/l添加し、またpH緩
衝剤としてほう酸を添加してpH3.00〜3.02に調整する。
めっき膜中の応力を緩和するためにサッカリンナトリウ
ムを添加し、その他に電解支持剤として塩化ナトリウ
ム、表面の濡れ特性のためにラウリル硫酸ナトリウムを
添加する。めっき液14の温度は電子恒温装置８を使用し
て23.0±0.1 ℃に調整する。めっき槽１への流量は調整
バルブ11aでは平均毎分５リットルとし、調整バルブ11b
によるノズル２への供給量は毎分600 ミリリットルと
する。An embodiment in which the permalloy alloy is plated using the apparatus configured as described above will be specifically described with numerical values. A permalloy alloy film is previously formed as a base on the wafer 10 set on the cathode 3 by a sputtering method. As the anode 4, a 2 mm thick sulfur-containing Ni metal plate is used. The plating solution 14 contains NiCl 2 · 6H 2 O as metal ions.
60 g / l, FeSO 4 .7H 2 O at 1.5 g / l and boric acid as a pH buffer are added to adjust the pH to 3.00 to 3.02.
Sodium saccharin is added to relieve the stress in the plated film, sodium chloride is added as an electrolytic support, and sodium lauryl sulfate is added for the wetting property of the surface. The temperature of the plating solution 14 is adjusted to 23.0 ± 0.1 ° C. by using the electronic thermostat 8. The flow rate to the plating tank 1 is 5 liters per minute on average for the adjusting valve 11a, and the adjusting valve 11b
The supply rate to the nozzle 2 is 600 ml / min.
【００１５】図４は本発明装置及び従来装置による薄膜
磁気ヘッドの上ポール部分へ施しためっき膜の鉄組成を
示すグラフである。×は米国特許4102756 号に開示され
ているものと同様の装置によるめっき膜の鉄組成を示
し、○は本発明装置によるめっき膜の鉄組成を示す。図
４から明らかな如く、本発明装置によるめっき膜の鉄組
成変動はほとんどなくなり、従来撹拌されにくかった後
端部26のくぼみ23においても改善されている。またウエ
ハ面上のめっき膜の分布は膜厚で２％、組成で0.3 ％以
内のばらつきであり、本発明装置によるめっき膜が均一
であることが判る。FIG. 4 is a graph showing the iron composition of the plating film applied to the upper pole portion of the thin film magnetic head by the device of the present invention and the conventional device. X indicates the iron composition of the plated film by the same device as disclosed in US Pat. No. 4,102,756, and ○ indicates the iron composition of the plated film by the device of the present invention. As is clear from FIG. 4, fluctuations in the iron composition of the plating film by the apparatus of the present invention are almost eliminated, and the depression 23 at the rear end portion 26, which has been difficult to stir conventionally, is also improved. Further, the distribution of the plating film on the wafer surface is within 2% in the film thickness and within 0.3% in the composition, which shows that the plating film by the apparatus of the present invention is uniform.
【００１６】なお本実施例ではめっき槽１にアクリル樹
脂を用いたが、非導電性、非磁性で酸性めっき浴と反応
しない材料であれば塩化ビニル樹脂、ポリプロピレン、
テフロン樹脂等を用いてもよい。またアノード４の材質
は白金のような不溶性のものも用いられるが通常はめっ
きされる単体金属もしくは合金と同じものが最も望まし
い。合金めっきの場合、同じ組成の合金板が手に入いら
なければ本実施例のように合金元素の一つと同じ元素の
単体金属でもよい。In this embodiment, an acrylic resin is used for the plating tank 1. However, if the material is non-conductive, non-magnetic and does not react with the acidic plating bath, vinyl chloride resin, polypropylene,
Teflon resin or the like may be used. An insoluble material such as platinum is also used as the material of the anode 4, but usually the same material as the single metal or alloy to be plated is most desirable. In the case of alloy plating, a single metal having the same element as one of the alloy elements may be used as in the present embodiment unless an alloy plate having the same composition is available.
【００１７】[0017]
【発明の効果】以上の如く本発明においてはめっき液の
均一な流れを発生し得る手段、すなわち被めっき物の被
めっき面に対してめっき液の撹拌と同時的にめっき液を
吹きつける手段を備えているのでミクロにパターニング
された凹凸のある微小な被めっき表面においても膜質、
組成、膜厚が精密に均一なめっき膜が得られる等本発明
は優れた効果を奏するものである。As described above, in the present invention, means for generating a uniform flow of the plating solution, that is, means for spraying the plating solution onto the surface to be plated of the object to be plated simultaneously with stirring the plating solution is provided. Since it is equipped with a film quality, even on a micro-patterned surface with microscopic unevenness
The present invention has excellent effects such as obtaining a plating film having a precise and uniform composition and film thickness.
【図１】本発明に係るめっき装置の模式的縦断面図及び
平面図である。FIG. 1 is a schematic vertical cross-sectional view and a plan view of a plating apparatus according to the present invention.
【図２】本発明に係るめっき装置に用いられるノズルの
模式的縦断面図である。FIG. 2 is a schematic vertical sectional view of a nozzle used in the plating apparatus according to the present invention.
【図３】本発明に係るめっき装置に用いられるノズル穴
の配置を示す下パドルの底面図である。FIG. 3 is a bottom view of the lower paddle showing the arrangement of nozzle holes used in the plating apparatus according to the present invention.
【図４】本発明装置及び従来装置によるめっき膜の鉄組
成を示すグラフである。FIG. 4 is a graph showing the iron composition of a plating film formed by the apparatus of the present invention and the conventional apparatus.
【図５】薄膜磁気ヘッドの模式的平面図及び模式的縦断
面図である。FIG. 5 is a schematic plan view and a schematic vertical sectional view of a thin film magnetic head.
【図６】従来装置によるめっき膜の鉄組成を示すグラフ
である。FIG. 6 is a graph showing an iron composition of a plating film formed by a conventional apparatus.
１ めっき槽 ２ ノズル ３ カソード ４ アノード ５ モータ ６ 上パドル ７ 下パドル 10 ウエハ 11a,11b 調整バルブ 12a,12b ポンプ 13 調整槽 14 めっき液 15 連結棒 16 クランク 23 くぼみ 27 ノズル穴 28 ガラス玉 30 管 1 plating tank 2 nozzle 3 cathode 4 anode 5 motor 6 upper paddle 7 lower paddle 10 wafer 11a, 11b adjusting valve 12a, 12b pump 13 adjusting tank 14 plating solution 15 connecting rod 16 crank 23 recess 27 nozzle hole 28 glass ball 30 tube
Claims (1)
っき物の被めっき面上にめっき液の流れを形成すべくな
しためっき装置において、被めっき物の被めっき面に対
してめっき液の撹拌と同時的にめっき液を吹きつける手
段を備えたことを特徴とするめっき装置。1. A plating apparatus configured to stir a plating solution in a plating tank to form a flow of the plating solution on the surface to be plated of the object to be plated. A plating apparatus comprising means for spraying a plating solution simultaneously with stirring the solution.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16703192A JPH05331679A (en) | 1992-06-01 | 1992-06-01 | Plating device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16703192A JPH05331679A (en) | 1992-06-01 | 1992-06-01 | Plating device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05331679A true JPH05331679A (en) | 1993-12-14 |
Family
ID=15842110
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16703192A Pending JPH05331679A (en) | 1992-06-01 | 1992-06-01 | Plating device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05331679A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010106369A (en) * | 2003-03-11 | 2010-05-13 | Ebara Corp | Plating apparatus |
-
1992
- 1992-06-01 JP JP16703192A patent/JPH05331679A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010106369A (en) * | 2003-03-11 | 2010-05-13 | Ebara Corp | Plating apparatus |
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