【０００１】
【発明が属する技術分野】
本発明は積層帯材の製造方法に関する。
【０００２】
【従来の技術】
二つの帯材を圧着接合して積層帯材を製造する方法には、例えば本発明者等の提案による特開２００１−１６２３８２号や特開２００２−０３６４２４号に示されるように、真空槽内で二つの帯材の被接合面に乾式成膜法により金属層を付着形成し該帯材同士を圧着接合する積層帯材の製造方法がある。
この方法は真空槽内で行う圧着接合のため比較的強固に接合可能な製造方法であり、また金属層の成膜と帯材の圧着接合を連続的に行うことができるため生産性が良く、更に同時に三層以上の積層帯材を得ることができ、この方法で得られた積層帯材の金属層をエッチングバリア層として機能させて、例えば印刷配線用の素材として最適なものとなる。
【０００３】
【発明が解決しようとする課題】
しかしながら、上述の方法で得られる積層帯材で高い接合強度を得ようとすると、積層帯材に拡散処理を施したり、予めイオンエッチング処理や酸洗処理を施したり、加熱処理するのが好適としているが、予めイオンエッチング処理や酸洗処理する方法では吸着した酸素や帯材表面に残留する汚染物質により付着形成する金属層と帯材との接合強度が部分的に弱くなり密着力が低下したり微細な空隙ができたりするという欠点があることを確認した。
また、加熱処理による方法では、電磁誘導による加熱、ランプによる加熱、通電抵抗加熱などが一般的であるが、広範囲において加熱するために材料を均一に加熱するのが難しく、特に材料の厚さが薄い場合には、材料の膨張が不均一となり、帯材にシワが発生するといった問題を生じる。
このことから、被接合面の表面を均一に加熱する方法が求められるようになった。
本発明の目的は、被接合面の表面を均一に加熱処理し、強固に接合した積層帯材を提供することにある。
【０００４】
【課題を解決するための手段】
本発明は上述の問題に鑑みてなされたものである。
即ち本発明は、真空槽内で二つの帯材を圧着接合する製造方法において、圧着接合前或いは更に圧着接合と同時に電子線により帯材の被接合面を加熱処理する積層帯材の製造方法である。
望ましくは、帯材の被接合面に金属を付着形成させるか、或いは清浄化処理と同時に、帯材の被接合面に金属を付着形成させる積層帯材の製造方法である。
【０００５】
【発明の実施の形態】
上述のように、本発明の主要な特徴は真空槽内で二つの帯材を例えば連続的に接合するのに際し、電子線の照射を行い、被接合表面を加熱処理することで、接合をより強固にすることにあり、電子線の照射による効果は帯材全体の加熱ではなく、表面に限定して加熱させることができるという効果を有する。
以下に本発明を詳しく説明する。
先ず、本発明では真空槽内に二つの帯材を設置する。このときの真空槽内の気圧は電子線を用いるためになるべく低い方が良く、好ましくは１Ｐａ以下であれば良い。帯材の材質は金属や樹脂フィルム等、帯状のものであれば用途に応じて材質を適宜選択できる。金属帯の場合であれば、金属帯の全部を加熱することなく被接合表面に付着する有機物や酸化物を除去する清浄化の効果も得られるし、例えば熱可塑性樹脂を帯材として用いれば、ハンドリング性を損なうことなく表面のみを軟化させることも可能である。
帯材の幅は生産性の観点からはなるべく広い方が良いが、圧着接合する観点からは幅が広すぎると接合が不均一になる等の問題が生じ易いので、３０００ｍｍ以下が望ましい。帯材の厚さは０．００５ｍｍ以上、３ｍｍ以下が望ましい。薄すぎるとしわが入り易く、また厚すぎると圧着が十分に行われない恐れがあるからである。
【０００６】
次に二つの帯材を連続的に巻出しながら、帯材の被接合表面に電子線を照射する。電子線の照射装置としては、ヒータを加熱し加速電圧を印加して熱電子を取出す、いわゆる電子銃を用いるのが良い。この時の加速電圧は５〜２００ｋＶ、ビーム電流は５〜１０００ｍＡが適当であるが、素材の材質や厚さに応じて適当に設定すればよい。
電子線は電気的若しくは磁気的に収束させてビーム状にした後、これに加わる電界若しくは磁界を周期的に変動させ、ビームの進行方向を周期的に変更し、この照射の範囲を接合幅と同程度とするのが良い。なお、接合の範囲が広い場合や処理に大容量が必要な場合は、電子線発生源を複数配置しても良いことはいうまでもない。
【０００７】
本発明では、この電子線の照射による加熱処理により、酸化物や有機物等を除去する清浄化の効果を得ることができる。また、電子線の照射によって、表面のみが加熱されることから、表面のみの加熱による接合力向上の効果も同時に得られる。
例えば予め酸洗等により、帯材の被接合面が清浄化処理されたものを素材として用いたり、材質が比較的活性な状態なものである場合では、本発明の電子線による照射で、被接合面の表面の汚染物質の除去や酸化物の除去が行えるため、その後の圧着接合で強固に接合することも可能である。
なお、素材が厚さ１ｍｍ以下の薄板である場合、電子線の照射により照射表面のみしか昇温しないように、照射面の反対面は冷却しても良いことはいうまでもない。
【０００８】
このような電子線の照射による加熱処理は接合の前若しくは接合時、若しくは接合前と接合時との両方で行う。
接合前に行えば、帯材の被接合表面を十分に清浄化することができ、例えばこの後に薄膜を形成して接合する場合に薄膜と帯材との接合強さを向上できる。
接合時に行う場合は、表面の清浄化と同時に接合させることができるため、被接合表面に不純物が再付着するなどの心配がない。また、加熱による軟化のため、接合強さが向上するなどの効果がある。さらに、被接合表面の凹凸や欠陥が除去されるなどの効果も期待できる。
接合前と接合時との両方に行うと、上記の両方の効果を得ることができるため、最も好ましい。
この電子線の照射は、接合する二つの帯材の両方に行うと、上述の効果を両方の帯材に付与できるため、最も好適である。
【０００９】
また、本発明の例としては、二つの帯材をロールにて圧着接合する前に一つもしくは複数の帯材の被接合面に金属を付着形成する。この付着方法としては、真空蒸着法、スパッタリング法、イオンプレーティング法、アークイオンプレーティング法、ＣＶＤ法等の乾式成膜方法が考えられるが、中でも真空蒸着法は真空槽内が低圧に保てるため好適である。
材質は要求される特性に応じて選択すればよく、例えば、Ｔｉ、Ａｇ、Ｓｎ、Ｎｉ、Ｃｕ、Ｃｒ、Ｚｒ、Ｉｎ、Ａｕ、Ｐｔ、Ｓｉ、Ａｌ、Ｃ、Ｗ等の純金属の他、これらの合金、化合物、酸化物、窒化物などでも良い。
なお、二つの帯材のそれぞれの被接合表面にそれぞれ別の方法で別の材質を付着形成しても良いことはいうまでもない。
【００１０】
また、本発明の例としては、この金属の付着形成と同時に帯材の被接合表面に電子線を照射して加熱処理を行う。これにより帯材の表面が清浄化されるのと同時に、気化している金属がプラズマ化して帯材に付着するため、より接合強さを向上させることができる。
そして、二つの帯材を例えば圧着ロールにて圧着接合し積層帯として巻取る。圧着ロールにて圧着接合する際のプレス荷重は高いほうが良いが、荷重が高すぎると圧着ロールにたわみを生じ、接合が不均一になったり、圧着ロール表面の損耗が激しくなったりするので、１０００ＭＰａ以下が好ましい。この際、同時に超音波振動を加えたり、圧着ロールの表面粗さを調整するなどして接合強さの向上を試みても良い。
なお、上述したように本発明の圧着接合は、ロール圧着を用いるのが好適である。
【００１１】
【実施例】
図１は本発明積層帯を製造するための一例を示す製造装置の概略図である。
１×１０−３Ｐａ程度に保たれた真空槽内において、帯材巻出し軸（１，１’）から帯材（２，２’）が順次巻出した。帯材は幅５００ｍｍ×長さ５００ｍ×厚さ９μｍのＣｕ箔を第一の帯材として、幅５００ｍｍ×長さ５００ｍ×厚さ７０μｍのＣｕ箔を第二の帯材を用いた。
そして、表面加熱処理用電子銃（３，３’），（４）により電子線を照射して加熱処理を行った。処理のタイミングは、▲１▼圧接接合前、▲２▼圧接接合と同時、▲３▼圧接接合前及び圧接接合と同時である。
金属の付着形成は、接合力向上のために図１に示すように、圧着ロール上で真空蒸着法により金属を付着させた。真空蒸着用電子銃（５，５’）により、真空蒸着材（６，６’）を気化させ、帯材（２，２’）の被接合面に付着形成した。
この後、圧着ロール（７，７’）にて圧着接合し、積層帯巻取り軸（８）により巻取った。
また、比較材として、予め酸洗による清浄化処理を行い、その後有機溶剤洗浄を施した材料を図１に示す装置を用いて加熱処理することなく、積層箔を製造した。材質及び帯材の寸法は同一なものとした。
【００１２】
こうして得られた積層帯材の接合強度及び、接合部の断面欠陥の有無を調べた。
接合強度はＪＩＳ Ｃ ５０１２（８．１項 導体の引きはがし強さ）に示される試験法に準拠して調査し、接合部の断面欠陥の有無は断面を電子顕微鏡で観察し、空隙等の内部欠陥の有無を調査した。その結果を表１にまとめて示す。
【００１３】
【表１】
【００１４】
表１に示すように、本発明の製造方法を適用したものでは接合強度が１．５ｋＮ／ｍ以上といった優れた特性と、内部欠陥の存在も確認されなかった。一方で、比較例は、接合部に空隙が確認された。
この結果から、本発明の製造方法を適用した積層帯材は、高い接合強度と内部欠陥のないものとなり、このような積層帯材は、付着形成した金属層を例えばエッチングバリア層、熱拡散バリア層として用いるような用途に好適となることが分かる。
【００１５】
【発明の効果】
本発明により、高い接合強度と内部欠陥のない積層帯材を製造することができ、エッチングバリア性、熱拡散バリア性の要求される積層材として利用されるに至った。
【図面の簡単な説明】
【図１】積層帯材の製造装置の一例を示す模式図である。
【符号の説明】
１，１´：帯材巻出し軸、２，２´：帯材、３，３´，４：表面清浄化用電子銃、５，５´：真空蒸着用電子銃、６，６´：真空蒸着材、７，７´：圧着ロール、８：積層帯巻取り軸[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a laminated strip.
[0002]
[Prior art]
A method for producing a laminated strip by press-bonding two strips is disclosed in, for example, JP-A-2001-162382 and JP-A-2002-036424 proposed by the present inventors, in a vacuum chamber. There is a manufacturing method of a laminated strip material in which a metal layer is adhered and formed on a surface to be joined of two strip materials by a dry film forming method, and the strip materials are pressure-bonded to each other.
This method is a manufacturing method capable of relatively strong bonding for pressure bonding performed in a vacuum chamber, and has high productivity because the metal layer can be continuously formed and the pressure bonding of the band material can be performed continuously. Further, three or more laminated strips can be obtained at the same time, and the metal layer of the laminated strip obtained by this method can function as an etching barrier layer, and becomes optimal as a material for printed wiring, for example.
[0003]
[Problems to be solved by the invention]
However, in order to obtain a high bonding strength with the laminated strip obtained by the above-described method, it is preferable to apply a diffusion treatment to the laminated strip, perform an ion etching treatment or a pickling treatment in advance, or perform a heat treatment. However, in the case of ion etching or pickling in advance, the bonding strength between the metal layer and the band formed by the adsorbed oxygen and the contaminants remaining on the surface of the band partially decreases, and the adhesion decreases. It has been confirmed that there is a drawback in that fine voids are formed.
In addition, in the method using a heat treatment, heating by electromagnetic induction, heating by a lamp, resistance heating, and the like are common, but it is difficult to uniformly heat the material because it is heated in a wide range, and particularly, the thickness of the material is small. If it is thin, the expansion of the material becomes non-uniform, causing a problem that wrinkles occur in the strip.
For this reason, a method for uniformly heating the surface to be joined has been required.
An object of the present invention is to provide a laminated band material in which a surface of a surface to be joined is uniformly heat-treated and strongly joined.
[0004]
[Means for Solving the Problems]
The present invention has been made in view of the above problems.
That is, the present invention relates to a manufacturing method for press-bonding two strips in a vacuum chamber, wherein the bonding surface of the strip is heat-treated with an electron beam before or simultaneously with the pressure bonding. is there.
Desirably, there is provided a method of manufacturing a laminated strip in which a metal is adhered and formed on a surface to be joined of a band or a metal is adhered and formed on a surface to be joined of a band simultaneously with a cleaning treatment.
[0005]
BEST MODE FOR CARRYING OUT THE INVENTION
As described above, a major feature of the present invention is that, for example, when two strips are continuously joined in a vacuum chamber, irradiation is performed with an electron beam, and the surface to be joined is subjected to a heat treatment, so that the joining is improved. The effect of the irradiation of the electron beam is that the strip is not heated but the surface of the strip can be heated only on the surface.
Hereinafter, the present invention will be described in detail.
First, in the present invention, two strips are installed in a vacuum chamber. At this time, the pressure in the vacuum chamber is preferably as low as possible because an electron beam is used, and preferably 1 Pa or less. The material of the band material can be appropriately selected according to the use as long as the material is a band such as a metal or a resin film. In the case of a metal strip, a cleaning effect of removing organic substances and oxides attached to the surface to be joined without heating the entire metal strip can be obtained.For example, if a thermoplastic resin is used as the strip, It is also possible to soften only the surface without impairing the handling.
The width of the strip is preferably as wide as possible from the viewpoint of productivity. However, from the viewpoint of pressure bonding, if the width is too wide, problems such as uneven bonding are likely to occur. The thickness of the strip is desirably from 0.005 mm to 3 mm. If the thickness is too small, wrinkles are likely to occur, and if the thickness is too large, there is a possibility that the pressure bonding may not be performed sufficiently.
[0006]
Next, while unwinding the two strips continuously, the surface to be joined of the strips is irradiated with an electron beam. As an electron beam irradiation device, it is preferable to use a so-called electron gun which heats a heater and applies an acceleration voltage to take out thermoelectrons. At this time, the acceleration voltage is suitably 5 to 200 kV and the beam current is suitably 5 to 1000 mA, but may be set appropriately according to the material and thickness of the material.
After converging the electron beam electrically or magnetically to form a beam, the electric field or magnetic field applied to it is periodically fluctuated, the beam traveling direction is changed periodically, and the range of this irradiation is determined by the junction width and It is better to be about the same. It is needless to say that a plurality of electron beam generating sources may be arranged when the range of bonding is large or when a large capacity is required for processing.
[0007]
In the present invention, the heat treatment by the irradiation of the electron beam can provide a cleaning effect of removing oxides, organic substances, and the like. Further, since only the surface is heated by the irradiation of the electron beam, the effect of improving the bonding strength by heating only the surface can be obtained at the same time.
For example, a material whose surface to be bonded is cleaned by pickling or the like in advance is used as a material, or when the material is in a relatively active state, the material is irradiated with the electron beam of the present invention. Since it is possible to remove contaminants and oxides on the surface of the bonding surface, it is possible to perform strong bonding by subsequent pressure bonding.
When the material is a thin plate having a thickness of 1 mm or less, it is needless to say that the surface opposite to the irradiation surface may be cooled so that only the irradiation surface is heated by electron beam irradiation.
[0008]
Such heat treatment by irradiation with an electron beam is performed before or at the time of bonding, or both before and during bonding.
By performing the bonding before the bonding, the surface to be bonded of the band can be sufficiently cleaned. For example, when a thin film is formed and bonded after that, the bonding strength between the thin film and the band can be improved.
When the bonding is performed, the bonding can be performed simultaneously with the cleaning of the surface, so that there is no fear that impurities are reattached to the surface to be bonded. In addition, since the material is softened by heating, there is an effect that the bonding strength is improved. Further, an effect of removing irregularities and defects on the surface to be joined can be expected.
It is most preferable to perform both before and at the time of joining since both effects described above can be obtained.
It is most preferable that the irradiation of the electron beam is performed on both of the two strips to be joined because the above-described effect can be imparted to both the strips.
[0009]
Further, as an example of the present invention, a metal is attached to one or a plurality of strips to be joined before the two strips are pressure-bonded by a roll. As a method for this deposition, a dry film formation method such as a vacuum evaporation method, a sputtering method, an ion plating method, an arc ion plating method, and a CVD method can be considered. Among them, the vacuum evaporation method is used because the pressure in the vacuum chamber can be kept low. It is suitable.
The material may be selected according to the required characteristics. For example, in addition to pure metals such as Ti, Ag, Sn, Ni, Cu, Cr, Zr, In, Au, Pt, Si, Al, C, and W, These alloys, compounds, oxides, nitrides and the like may be used.
Needless to say, different materials may be attached and formed on the respective joined surfaces of the two strips by different methods.
[0010]
As an example of the present invention, a heat treatment is performed by irradiating an electron beam to the surface to be joined of the strip at the same time as the formation of the adhesion of the metal. Accordingly, the surface of the strip is cleaned, and at the same time, the vaporized metal is turned into plasma and adheres to the strip, so that the bonding strength can be further improved.
Then, the two strips are pressure-bonded, for example, by a pressure roll, and wound up as a laminated strip. The higher the press load at the time of pressure bonding with the pressure roller, the better. The following is preferred. At this time, it is also possible to try to improve the bonding strength by simultaneously applying ultrasonic vibration or adjusting the surface roughness of the pressure roll.
Note that, as described above, the pressure bonding of the present invention preferably uses roll pressure bonding.
[0011]
【Example】
FIG. 1 is a schematic view of a manufacturing apparatus showing an example for manufacturing the laminated band of the present invention.
In the vacuum chamber maintained at about 1 × 10 −3 Pa, the strip (2, 2 ′) was sequentially unwound from the strip unwinding shaft (1, 1 ′). As the band, a Cu foil having a width of 500 mm × length 500 m × a thickness of 9 μm was used as a first band, and a Cu foil having a width of 500 mm × length 500 m × a thickness of 70 μm was used as a second band.
Then, heat treatment was performed by irradiating an electron beam with the surface heating electron guns (3, 3 ′) and (4). The timing of the processing is (1) before press-joining, (2) simultaneously with press-joining, and (3) before press-joining and simultaneously with press-joining.
As shown in FIG. 1, the metal was deposited on a pressure roll by a vacuum evaporation method to improve the bonding strength. The vacuum deposition material (6, 6 ') was vaporized by the electron gun for vacuum deposition (5, 5'), and was adhered and formed on the joining surface of the strip (2, 2 ').
After that, they were bonded by pressure bonding with pressure bonding rolls (7, 7 ') and wound up by a lamination band winding shaft (8).
Further, as a comparative material, a laminated foil was manufactured without subjecting a material subjected to a cleaning treatment by pickling in advance and then subjected to an organic solvent cleaning to a heat treatment using the apparatus shown in FIG. The material and the dimensions of the strip were the same.
[0012]
The bonding strength of the laminated strip thus obtained and the presence or absence of a cross-sectional defect at the bonding portion were examined.
The joint strength is investigated in accordance with the test method specified in JIS C 5012 (section 8.1 Conductor peeling strength). The presence or absence of cross-sectional defects at the joints is observed by observing the cross-section with an electron microscope. The presence or absence of defects was investigated. The results are summarized in Table 1.
[0013]
[Table 1]
[0014]
As shown in Table 1, in the case where the manufacturing method of the present invention was applied, excellent characteristics such as a joining strength of 1.5 kN / m or more and the presence of internal defects were not confirmed. On the other hand, in the comparative example, a void was confirmed at the joint.
From this result, the laminated strip to which the manufacturing method of the present invention is applied has a high bonding strength and no internal defects, and such a laminated strip is formed by depositing a metal layer such as an etching barrier layer and a heat diffusion barrier. It can be seen that this is suitable for use as a layer.
[0015]
【The invention's effect】
According to the present invention, a laminated strip having high bonding strength and no internal defects can be manufactured, and has been used as a laminated material requiring an etching barrier property and a thermal diffusion barrier property.
[Brief description of the drawings]
FIG. 1 is a schematic view showing an example of an apparatus for manufacturing a laminated strip.
[Explanation of symbols]
1, 1 ': strip unwinding shaft, 2, 2': strip, 3, 3 ', 4: electron gun for surface cleaning, 5, 5': electron gun for vacuum evaporation, 6, 6 ': vacuum Evaporation material, 7, 7 ': Crimping roll, 8: Laminated band winding shaft
