JP2011181839A - Wire bonding method - Google Patents

Wire bonding method Download PDF

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JP2011181839A
JP2011181839A JP2010046935A JP2010046935A JP2011181839A JP 2011181839 A JP2011181839 A JP 2011181839A JP 2010046935 A JP2010046935 A JP 2010046935A JP 2010046935 A JP2010046935 A JP 2010046935A JP 2011181839 A JP2011181839 A JP 2011181839A
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wire
electrode
unevenness
ball
bonding method
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JP5381816B2 (en
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Junji Fujino
純司 藤野
Hiroaki Ichinohe
洋暁 一戸
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Mitsubishi Electric Corp
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Mitsubishi Electric Corp
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    • H01L24/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L24/85—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a wire connector
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    • H01L2224/02—Bonding areas; Manufacturing methods related thereto
    • H01L2224/04—Structure, shape, material or disposition of the bonding areas prior to the connecting process
    • H01L2224/05—Structure, shape, material or disposition of the bonding areas prior to the connecting process of an individual bonding area
    • H01L2224/0554—External layer
    • H01L2224/0555—Shape
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    • H01L2224/48465—Connecting portions the connecting portion on the bonding area of the semiconductor or solid-state body being a ball bond the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
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  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Laser Beam Processing (AREA)
  • Wire Bonding (AREA)
  • Pressure Welding/Diffusion-Bonding (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To improve bondability of wire bonding used for a mounting substrate for a semiconductor package and electronic components. <P>SOLUTION: Striped first unevenness 16 is formed by irradiating a top surface of a ball 14 formed atop of a wire 12 with femtosecond laser. Then the ball 14 is brought into contact with a first electrode 20 and then crushed while ultrasonic vibration is applied, thereby bonding the wire 12 to the first electrode 20. Here, a direction wherein the first unevenness 16 extends is orthogonal to an amplitude direction of ultrasonic vibration. Consequently, crystal of a bonding interface is made fine, so that plastic deformation is easily caused even with a low load and the metal diffusion bonding is facilitated to improve bondability. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

本発明は、半導体パッケージや電子部品の基板実装で用いられるワイヤボンディング方法に関し、特に接合性を向上することができるワイヤボンディング方法に関する。   The present invention relates to a wire bonding method used for mounting a semiconductor package or an electronic component on a substrate, and more particularly to a wire bonding method capable of improving bondability.

従来のワイヤボンディングでは、まず、キャピラリから導出されたワイヤの先端をアーク放電や火炎によって溶融させてボールを形成する。次に、ボールを第１の電極に接触させてキャピラリにより超音波振動を印加しながら押し潰して、ワイヤを第１の電極にボンディングする。次に、キャピラリにより加重及び超音波振動を印加することにより、ワイヤを第２の電極にボンディングする。この際に、第１の電極と第２の電極との間においてワイヤが屈曲部を有するループ状になる。   In conventional wire bonding, first, the tip of the wire led out from the capillary is melted by arc discharge or flame to form a ball. Next, the ball is brought into contact with the first electrode and squeezed while applying ultrasonic vibration with a capillary to bond the wire to the first electrode. Next, the wire is bonded to the second electrode by applying a load and ultrasonic vibration with a capillary. At this time, the wire has a loop shape having a bent portion between the first electrode and the second electrode.

なお、機械部品等の密着面の密着性を向上させるために、フェムト秒レーザを用いて密着面に微細周期構造を形成する方法が開示されている（例えば、特許文献１参照）。しかし、ワイヤと電極との接合性を向上させることについては何ら開示されていない。   In addition, a method of forming a fine periodic structure on a close contact surface using a femtosecond laser is disclosed in order to improve the close contact property of a mechanical part or the like (see, for example, Patent Document 1). However, nothing is disclosed about improving the bondability between the wire and the electrode.

特許４０９２２５６号公報Japanese Patent No. 40922256

ワイヤボンドのボールは、溶融した後に大気中への自然放熱によって融点以下まで冷却されて凝固する。これは緩やかな凝固のため、結晶の寸法は数十μｍにおよぶ場合が多い。結晶寸法が大きいと、荷重によるズレが生じやすい結晶粒界が少ないため、塑性変形しにくい。さらに、金属拡散速度の大きい粒界が少ないため、金属接合しにくい。   After being melted, the wire bond ball is cooled to below the melting point by natural heat dissipation to the atmosphere and solidifies. This is a slow solidification, and the crystal size often reaches several tens of μm. When the crystal size is large, there are few crystal grain boundaries that are likely to be displaced due to load, and therefore, plastic deformation is difficult. Furthermore, since there are few grain boundaries with a high metal diffusion rate, metal bonding is difficult.

特に、高密度実装を実現しようとするとワイヤボンドの狭ピッチ化が必要となり、ボールサイズが小さくなると、ボールに含まれる結晶の数が少なくなり、この傾向が顕在化する恐れがある。また、高密度実装の目的で半導体チップを積層する場合、チップが薄くなるため、チップ破壊を防止するために低荷重での接合が重要となり、塑性変形のしやすさが必須となる。   In particular, to achieve high-density mounting, it is necessary to reduce the pitch of wire bonds. When the ball size is reduced, the number of crystals contained in the ball is reduced, and this tendency may become apparent. Further, when stacking semiconductor chips for the purpose of high-density mounting, since the chips are thinned, bonding with a low load is important to prevent chip breakage, and ease of plastic deformation is essential.

また、半導体素子やプリント基板の電極は、めっきや蒸着により数μｍ以下の薄さで形成される。このため、電極の結晶寸法は１μｍ程度となることが多い。Ａｕ線をワイヤとして用いる場合、電極がＡｕであれば比較的良好な接合性が期待できる。しかし、ボールと電極で結晶寸法が大きく違う場合には、相互拡散が遅くなり、接合性が低下する可能性がある。   Further, the electrodes of the semiconductor element and the printed circuit board are formed with a thickness of several μm or less by plating or vapor deposition. For this reason, the crystal size of the electrode is often about 1 μm. When using an Au wire as a wire, relatively good bonding properties can be expected if the electrode is Au. However, when the crystal dimensions of the ball and the electrode are greatly different, the interdiffusion is slowed and the bonding property may be lowered.

本発明は、上述のような課題を解決するためになされたもので、その目的は、接合性を向上することができるワイヤボンディング方法を得るものである。   The present invention has been made to solve the above-described problems, and an object of the present invention is to obtain a wire bonding method capable of improving bondability.

本発明は、ワイヤの先端に形成されたボールの表面にフェムト秒レーザを照射して縞状の第１の凹凸を形成する工程と、前記ボールを第１の電極に接触させて超音波振動を印加しながら押し潰すことにより、前記ワイヤを前記第１の電極にボンディングする工程とを備え、前記第１の凹凸が延びる方向は、前記超音波振動の振幅方向に直交することを特徴とするワイヤボンディング方法である。   The present invention includes a step of irradiating a surface of a ball formed at the tip of a wire with a femtosecond laser to form first striped irregularities, and contacting the ball with a first electrode to cause ultrasonic vibration. A step of bonding the wire to the first electrode by crushing while applying, and a direction in which the first unevenness extends is perpendicular to an amplitude direction of the ultrasonic vibration. It is a bonding method.

本発明により、接合性を向上することができる。   According to the present invention, the bondability can be improved.

本発明の実施の形態に係るワイヤボンディング方法を説明するための断面図である。It is sectional drawing for demonstrating the wire bonding method which concerns on embodiment of this invention. 本発明の実施の形態に係るワイヤボンディング方法を説明するための断面図である。It is sectional drawing for demonstrating the wire bonding method which concerns on embodiment of this invention. 本発明の実施の形態に係るワイヤボンディング方法を説明するための断面図である。It is sectional drawing for demonstrating the wire bonding method which concerns on embodiment of this invention. 本発明の実施の形態に係るワイヤボンディング方法を説明するための断面図である。It is sectional drawing for demonstrating the wire bonding method which concerns on embodiment of this invention. 本発明の実施の形態に係るワイヤボンディング方法を説明するための断面図である。It is sectional drawing for demonstrating the wire bonding method which concerns on embodiment of this invention. 本発明の実施の形態に係るワイヤボンディング方法を説明するための断面図である。It is sectional drawing for demonstrating the wire bonding method which concerns on embodiment of this invention.

本発明の実施の形態に係るワイヤボンディング方法について図面を参照しながら説明する。図１〜６は、本発明の実施の形態に係るワイヤボンディング方法を説明するための断面図である。   A wire bonding method according to an embodiment of the present invention will be described with reference to the drawings. 1 to 6 are cross-sectional views for explaining a wire bonding method according to an embodiment of the present invention.

まず、図１に示すように、キャピラリ１０から導出されたワイヤ１２の先端に、照射出力を大きくしたフェムト秒レーザを照射して溶融させて、ボール１４を形成する。   First, as shown in FIG. 1, the tip of the wire 12 led out from the capillary 10 is irradiated with a femtosecond laser with an increased irradiation output to be melted to form a ball 14.

次に、図２に示すように、ワイヤ１２の先端に形成されたボール１４の下半分の表面にフェムト秒レーザを照射する。ここで、例えばフェムト秒レーザの波長を８００ｎｍ、パルスエネルギーを１ｍＪ、繰り返しを１ｋＨｚ、パルス幅を２００ｆｓとする。これにより、ボール１４の表面に、１μｍ以下の縞状の第１の凹凸１６が形成される。この凹凸は、ボール１４の表面に形成されたリップル又はナノ周期構造である。   Next, as shown in FIG. 2, a femtosecond laser is irradiated on the surface of the lower half of the ball 14 formed at the tip of the wire 12. Here, for example, the wavelength of the femtosecond laser is 800 nm, the pulse energy is 1 mJ, the repetition is 1 kHz, and the pulse width is 200 fs. As a result, striped first irregularities 16 of 1 μm or less are formed on the surface of the ball 14. This unevenness is a ripple or nano-periodic structure formed on the surface of the ball 14.

この際に、レーザ光の出力を制御することで、ボール１４の溶融状態から一旦冷却されて固体化する前に表面に第１の凹凸１６を形成する。これにより、凝固に伴う残留応力を低減させ、信頼性の高いワイヤボンド部を形成することができる。   At this time, by controlling the output of the laser beam, the first unevenness 16 is formed on the surface before the ball 14 is once cooled from the molten state and solidified. Thereby, the residual stress accompanying solidification can be reduced, and a highly reliable wire bond portion can be formed.

次に、図３に示すように、半導体チップ１８上に形成された第１の電極２０の表面に、フェムト秒レーザを照射して縞状の第２の凹凸２２を形成する。この際に、第１の凹凸１６の形成時とレーザの波長を同じにし、更に好ましくは第１の電極２０の構造、材質、厚み、及びメタライズの製法などに応じてレーザの波長及び出力を調整して、第１の凹凸１６と第２の凹凸２２をほぼ等しい寸法（周期）にする。   Next, as shown in FIG. 3, the surface of the first electrode 20 formed on the semiconductor chip 18 is irradiated with a femtosecond laser to form second striped irregularities 22. At this time, the wavelength of the laser is made the same as that at the time of forming the first unevenness 16, and more preferably, the wavelength and output of the laser are adjusted according to the structure, material, thickness, metallization manufacturing method, etc. of the first electrode 20. Then, the first unevenness 16 and the second unevenness 22 are made to have substantially the same size (period).

次に、図４に示すように、ボール１４を第１の電極２０に接触させてキャピラリ１０により超音波振動を印加しながら押し潰す。これにより、ワイヤ１２を第１の電極２０にボンディングする。ここで、第１の凹凸１６及び第２の凹凸２２が延びる方向は、超音波振動の振幅方向に直交する。これにより、低荷重でも良好な接合性を得ることができる。なお、半導体チップ１８はプリント基板２４上に搭載されている。プリント基板２４上には第２の電極２６が形成されている。   Next, as shown in FIG. 4, the ball 14 is brought into contact with the first electrode 20 and crushed while applying ultrasonic vibration by the capillary 10. Thereby, the wire 12 is bonded to the first electrode 20. Here, the direction in which the first unevenness 16 and the second unevenness 22 extend is orthogonal to the amplitude direction of the ultrasonic vibration. Thereby, good bondability can be obtained even with a low load. The semiconductor chip 18 is mounted on the printed board 24. A second electrode 26 is formed on the printed circuit board 24.

次に、図５に示すように、ワイヤ１２の屈曲部（後述）となる部分にフェムト秒レーザを照射して屈曲方向に直交する縞状の第３の凹凸２８を形成する。また、１回目のワイヤボンディングと同様に、ワイヤ１２のボンディング部分及び第２の電極２６の表面にフェムト秒レーザを照射して、超音波振動の振幅方向に直交する縞状の凹凸を形成する。   Next, as shown in FIG. 5, a portion that becomes a bent portion (described later) of the wire 12 is irradiated with a femtosecond laser to form a striped third unevenness 28 orthogonal to the bending direction. Similarly to the first wire bonding, the bonding portion of the wire 12 and the surface of the second electrode 26 are irradiated with a femtosecond laser to form striped irregularities orthogonal to the amplitude direction of the ultrasonic vibration.

次に、図６に示すように、キャピラリ１０により加重及び超音波振動を印加することにより、第２の電極２６にワイヤ１２をボンディングする。この際に、第１の電極２０と第２の電極２６との間においてワイヤ１２が屈曲部３０を有するループ状になる。なお、プリント基板２４はホットプレート上に置かれ、加熱された状態である。   Next, as shown in FIG. 6, the wire 12 is bonded to the second electrode 26 by applying a load and ultrasonic vibration by the capillary 10. At this time, the wire 12 has a loop shape having a bent portion 30 between the first electrode 20 and the second electrode 26. The printed circuit board 24 is placed on a hot plate and heated.

以上説明したように、本実施の形態では、ボールの表面にフェムト秒レーザを照射して、超音波振動の振幅方向に直交する縞状の凹凸を形成する。これにより、接合界面の結晶が微細化されるため、低荷重でも塑性変形がしやすく、金属拡散接合しやすくなり、接合性が向上する。   As described above, in this embodiment, the surface of the ball is irradiated with a femtosecond laser to form striped irregularities orthogonal to the amplitude direction of the ultrasonic vibration. Thereby, since the crystal | crystallization of a joining interface is refined | miniaturized, it becomes easy to carry out plastic deformation | transformation by a low load, becomes easy to carry out metal diffusion joining, and joinability improves.

また、レーザを照射して接合部のワイヤや電極の温度を上昇させることで、塑性変形しやすくなり、接合性を高めることができる。さらに、塑性変形に伴う残留応力を低減することもできる。   Further, by raising the temperature of the wire or electrode at the joint by irradiating with a laser, plastic deformation is likely to occur, and the bondability can be improved. Furthermore, the residual stress accompanying plastic deformation can also be reduced.

また、ワイヤボンドする電極の表面にもレーザを照射することにより、ボールの表面と結晶寸法を揃えて接合性を高めることができる。さらに、第１の電極の構造及び材質などに応じてレーザの波長及び出力を調整することで、第１の凹凸と第２の凹凸をほぼ等しい寸法にすることができる。   Further, by irradiating the surface of the electrode to be wire-bonded with a laser, it is possible to align the crystal dimensions with the surface of the ball and to improve the bondability. Furthermore, by adjusting the wavelength and output of the laser according to the structure and material of the first electrode, the first unevenness and the second unevenness can be made to have substantially the same size.

また、ボールの形成と凹凸の形成を同じレーザによって行うことで、生産性を改善することができる。   Further, productivity can be improved by forming the ball and the unevenness with the same laser.

また、ループ状のワイヤの屈曲部にもレーザを照射することで、塑性変形に伴う粒界を起点としたクラックの発生を抑制することができる。   In addition, by irradiating the bent portion of the loop-shaped wire with laser, it is possible to suppress the generation of cracks starting from the grain boundary accompanying plastic deformation.

なお、フェムト秒レーザの光源として、例えばCyber Laser社製の光源を用いる。ただし、リップル形成可能なレーザであれば他の波長・出力のレーザでも同様の効果が得られる。また、ワイヤは例えばＡｕ線だが、ＡｌやＣｕなど他の金属ワイヤでも同様の効果が得られる。また、明確な縞状の凹凸（ナノ周期構造）が形成されなくても、レーザを照射された最表面の結晶寸法が微細化されれば同様の効果が得られる。   For example, a light source manufactured by Cyber Laser is used as the light source of the femtosecond laser. However, the same effect can be obtained with lasers having other wavelengths and outputs as long as the laser can generate ripples. The wire is, for example, Au wire, but the same effect can be obtained with other metal wires such as Al and Cu. Even if clear stripe-shaped irregularities (nano-periodic structure) are not formed, the same effect can be obtained if the crystal size of the outermost surface irradiated with the laser is miniaturized.

１２ ワイヤ
１４ ボール
１６ 第１の凹凸
２２ 第２の凹凸
２６ 第２の電極
２８ 第３の凹凸
３０ 屈曲部 12 Wire 14 Ball 16 First unevenness 22 Second unevenness 26 Second electrode 28 Third unevenness 30 Bending portion

Claims (5)

ワイヤの先端に形成されたボールの表面にフェムト秒レーザを照射して縞状の第１の凹凸を形成する工程と、
前記ボールを第１の電極に接触させて超音波振動を印加しながら押し潰すことにより、前記ワイヤを前記第１の電極にボンディングする工程とを備え、
前記第１の凹凸が延びる方向は、前記超音波振動の振幅方向に直交することを特徴とするワイヤボンディング方法。 Irradiating the surface of a ball formed at the tip of the wire with a femtosecond laser to form first striped irregularities;
Bonding the wire to the first electrode by bringing the ball into contact with the first electrode and crushing while applying ultrasonic vibration,
The wire bonding method characterized in that a direction in which the first unevenness extends is orthogonal to an amplitude direction of the ultrasonic vibration. 前記第１の電極の表面にフェムト秒レーザを照射して縞状の第２の凹凸を形成する工程を更に備え、
前記第２の凹凸が延びる方向は、前記超音波振動の振幅方向に直交することを特徴とする請求項１に記載のワイヤボンディング方法。 Further comprising the step of irradiating the surface of the first electrode with a femtosecond laser to form striped second irregularities;
The wire bonding method according to claim 1, wherein a direction in which the second unevenness extends is perpendicular to an amplitude direction of the ultrasonic vibration. 前記第１の電極の構造及び材質に応じて前記フェムト秒レーザの波長及び出力を調整して、前記第１の凹凸と前記第２の凹凸をほぼ等しい寸法にすることを特徴とする請求項２に記載のワイヤボンディング方法。   3. The wavelength and output of the femtosecond laser are adjusted according to the structure and material of the first electrode so that the first unevenness and the second unevenness are approximately equal in size. The wire bonding method as described in. 前記第１の凹凸を形成する前に、前記ワイヤの先端にフェムト秒レーザを照射して前記ボールを形成する工程を更に備えることを特徴とする請求項１〜３の何れか１項に記載のワイヤボンディング方法。   4. The method according to claim 1, further comprising a step of irradiating a tip of the wire with a femtosecond laser to form the ball before forming the first unevenness. 5. Wire bonding method. 前記ワイヤを前記第１の電極にボンディングした後に前記ワイヤを第２の電極にボンディングして、前記第１の電極と前記第２の電極の間において前記ワイヤが屈曲部を有するループ状になるようにする工程と、
前記ワイヤを前記第２の電極にボンディングする前に、前記ワイヤの前記屈曲部となる部分にフェムト秒レーザを照射して屈曲方向に直交する縞状の第３の凹凸を形成する工程とを更に備えることを特徴とする請求項１〜４の何れか１項に記載のワイヤボンディング方法。 After the wire is bonded to the first electrode, the wire is bonded to the second electrode so that the wire has a loop shape having a bent portion between the first electrode and the second electrode. And the process of
Before bonding the wire to the second electrode, the step of irradiating a portion that becomes the bent portion of the wire with a femtosecond laser to form striped third unevenness perpendicular to the bending direction; The wire bonding method according to claim 1, further comprising: a wire bonding method according to claim 1.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5546670B1 (en) * 2013-06-13 2014-07-09 田中電子工業株式会社 Structure of coated copper wire for ultrasonic bonding
CN109332901A (en) * 2018-09-14 2019-02-15 深圳市商德先进陶瓷股份有限公司 Ceramic chopper and preparation method thereof and application

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6248033A (en) * 1985-08-28 1987-03-02 Nec Corp Wire bonding method
JP2004360012A (en) * 2003-06-04 2004-12-24 Laser Gijutsu Sogo Kenkyusho Method and device for surface treatment of close-contact metal surface
JP2006210534A (en) * 2005-01-26 2006-08-10 Sumitomo Electric Hardmetal Corp Mounting tool
JP2010105043A (en) * 2008-10-03 2010-05-13 Nissan Motor Co Ltd Low temperature joining method for metal
JP2011119563A (en) * 2009-12-07 2011-06-16 Denso Corp Wire bonding method and semiconductor device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6248033A (en) * 1985-08-28 1987-03-02 Nec Corp Wire bonding method
JP2004360012A (en) * 2003-06-04 2004-12-24 Laser Gijutsu Sogo Kenkyusho Method and device for surface treatment of close-contact metal surface
JP2006210534A (en) * 2005-01-26 2006-08-10 Sumitomo Electric Hardmetal Corp Mounting tool
JP2010105043A (en) * 2008-10-03 2010-05-13 Nissan Motor Co Ltd Low temperature joining method for metal
JP2011119563A (en) * 2009-12-07 2011-06-16 Denso Corp Wire bonding method and semiconductor device

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5546670B1 (en) * 2013-06-13 2014-07-09 田中電子工業株式会社 Structure of coated copper wire for ultrasonic bonding
JP2015002213A (en) * 2013-06-13 2015-01-05 田中電子工業株式会社 Structure of coating copper wire for ultrasonic bonding
CN109332901A (en) * 2018-09-14 2019-02-15 深圳市商德先进陶瓷股份有限公司 Ceramic chopper and preparation method thereof and application

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