JPH05175272A - Pd superfine wire for semiconductor element use and method of forming ball consisting of that - Google Patents
Pd superfine wire for semiconductor element use and method of forming ball consisting of thatInfo
- Publication number
- JPH05175272A JPH05175272A JP3341321A JP34132191A JPH05175272A JP H05175272 A JPH05175272 A JP H05175272A JP 3341321 A JP3341321 A JP 3341321A JP 34132191 A JP34132191 A JP 34132191A JP H05175272 A JPH05175272 A JP H05175272A
- Authority
- JP
- Japan
- Prior art keywords
- wire
- ball
- hydrogen
- superfine wire
- extra fine
- 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
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
- H01L24/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
- H01L24/42—Wire connectors; Manufacturing methods related thereto
- H01L24/44—Structure, shape, material or disposition of the wire connectors prior to the connecting process
- H01L24/45—Structure, shape, material or disposition of the wire connectors prior to the connecting process of an individual wire connector
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
- H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
- H01L2224/42—Wire connectors; Manufacturing methods related thereto
- H01L2224/44—Structure, shape, material or disposition of the wire connectors prior to the connecting process
- H01L2224/45—Structure, shape, material or disposition of the wire connectors prior to the connecting process of an individual wire connector
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
- H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
- H01L2224/42—Wire connectors; Manufacturing methods related thereto
- H01L2224/44—Structure, shape, material or disposition of the wire connectors prior to the connecting process
- H01L2224/45—Structure, shape, material or disposition of the wire connectors prior to the connecting process of an individual wire connector
- H01L2224/45001—Core members of the connector
- H01L2224/45099—Material
- H01L2224/451—Material with a principal constituent of the material being a metal or a metalloid, e.g. boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te) and polonium (Po), and alloys thereof
- H01L2224/45163—Material with a principal constituent of the material being a metal or a metalloid, e.g. boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te) and polonium (Po), and alloys thereof the principal constituent melting at a temperature of greater than 1550°C
- H01L2224/45164—Palladium (Pd) as principal constituent
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
- H01L2224/80—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
- H01L2224/85—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
- H01L2224/85009—Pre-treatment of the connector or the bonding area
- H01L2224/8503—Reshaping, e.g. forming the ball or the wedge of the wire connector
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
- H01L2924/0001—Technical content checked by a classifier
- H01L2924/00014—Technical content checked by a classifier the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
- H01L2924/01—Chemical elements
- H01L2924/01046—Palladium [Pd]
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
- H01L2924/10—Details of semiconductor or other solid state devices to be connected
- H01L2924/11—Device type
- H01L2924/14—Integrated circuits
Landscapes
- Engineering & Computer Science (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Wire Bonding (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は半導体素子用のＰｄ極細
線、詳しくは半導体チップ上の電極と外部リードとを接
続するワイヤボンディング用又はバンプ電極用の 0.1mm
φ以下のＰｄ極細線および該Ｐｄ極細線のボール形成方
法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Pd ultrafine wire for a semiconductor element, more specifically 0.1 mm for wire bonding or bump electrode for connecting an electrode on a semiconductor chip and an external lead.
The present invention relates to a Pd extra fine wire having a diameter of φ or less and a ball forming method for the Pd extra fine wire.
【０００２】[0002]
【従来の技術】従来、ワイヤボンディング用のＰｄ極細
線として、高純度Ｐｄに希土類元素，Ｈｇ，Ｓｉ，Ｃ
ａ，Ａｌ等の卑金属を添加した組成のＰｄ極細線とし、
それにより該極細線の機械的強度を改善することが知ら
れている（特公昭62-43541号公報あるいは特公昭61-120
11号公報）。2. Description of the Related Art Conventionally, as a Pd extra fine wire for wire bonding, rare earth elements, Hg, Si and C are added to high purity Pd.
a Pd extra fine wire having a composition to which a base metal such as a or Al is added,
It is known that this improves the mechanical strength of the ultrafine wire (Japanese Patent Publication No. 62-43541 or Japanese Patent Publication No. 61-120).
No. 11 bulletin).
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、上記従
来のＰｄ極細線は前記卑金属の添加量が多くなると破断
強度など機械的強度は増強されるが、ワイヤボンディン
グ時あるいはバンプ形成時において、スパーク等の放電
加熱によりボールを形成する際にボール表面に酸化膜が
生成されるために、ボールに歪が生じるなど真球度が低
くなり所定の接合強度が得られないという不具合があっ
た。すなわち、ボール形成時のボール真球度が得られな
いために機械的強度の改善に限度があった。However, the above-mentioned conventional Pd ultrafine wire has an increased mechanical strength such as breaking strength when the amount of the base metal added is increased. However, during the wire bonding or the bump formation, sparks or the like are not formed. Since an oxide film is formed on the surface of the ball when the ball is formed by electric discharge heating, there is a problem that the sphericity is lowered due to distortion of the ball and a predetermined bonding strength cannot be obtained. That is, since the ball sphericity at the time of ball formation cannot be obtained, there is a limit to the improvement of mechanical strength.
【０００４】本発明は斯る従来事情に鑑み、機械的強度
を十分に確保すると同時にボール形成時のボール真球度
を高めて接合強度を高め得、信頼性の高い半導体装置の
作製に有用なＰｄ極細線及びそのボール形成方法を提供
することを目的とする。In view of such conventional circumstances, the present invention is useful for manufacturing a highly reliable semiconductor device, which can secure sufficient mechanical strength and at the same time increase the ball sphericity at the time of ball formation to increase the bonding strength. An object is to provide a Pd ultrafine wire and a ball forming method thereof.
【０００５】[0005]
【課題を解決するための手段】斯る本発明のＰｄ極細線
は、卑金属を含有せるＰｄ極細線に水素を吸収させてな
ることを特徴とする。The Pd extra fine wire of the present invention is characterized in that the Pd extra fine wire containing a base metal absorbs hydrogen.
【０００６】又、本発明のＰｄ極細線のボール形成方
法、卑金属を含有せるＰｄ極細線に水素を吸収させた状
態にし、該Ｐｄ極細線を放電加熱してボールを形成する
ことを特徴とするFurther, the Pd extra fine wire ball forming method of the present invention is characterized in that a Pd extra fine wire containing a base metal is made to absorb hydrogen, and the Pd extra fine wire is heated by discharge to form a ball.
【０００７】[0007]
【作用】本発明によれば、Ｐｄ極細線が水素を吸収して
いるので、該Ｐｄ極細線を放電加熱したボール形成時
に、Ｐｄ極細線が溶融してそれに吸収されている水素を
放出することにより、ボール周囲に水素ガスの雰囲気が
形成されてＰｄ極細線に含有している卑金属の酸化が防
止される。従って、ボールがいびつにならずボール真球
度が向上する。According to the present invention, since the Pd extra fine wire absorbs hydrogen, the Pd extra fine wire is melted and the hydrogen absorbed therein is released when a ball is formed by heating the Pd extra fine wire by discharge heating. As a result, an atmosphere of hydrogen gas is formed around the ball to prevent the base metal contained in the Pd ultrafine wire from being oxidized. Therefore, the ball is not distorted and the sphericity of the ball is improved.
【０００８】[0008]
【実施例】Ｐｄ極細線は、高純度Ｐｄに希土類元素（Ｌ
ａ，Ｃｅ等、原子番号５７〜７１の元素），Ｇｅ，Ｂ
ｅ，Ｈｇ，Ｓｉ，Ｃａ，Ａｌ等の卑金属を添加させたも
の、詳しくは、高純度Ｐｄ（不可避不純物を含む）と添
加元素とからなる組成のＰｄ合金を溶解鋳造し、次いで
溝ロール加工を施し、その途中で焼鈍処理を施した後に
線引加工で線径２５μｍの母線に作製し、さらに十分な
応力除去を行った後にスプールに巻き取られ保管され
る。このスプールはワイヤボンディング機に装着されて
該ボンディング機の使用時に、前記Ｐｄ極細線を繰出し
ながらキャピラリーに供給し、Ｐｄ極細線の先端をスパ
ークにより放電加熱して該先端をボール状に形成し、こ
のボールをキャピラリーの下降により半導体素子のチッ
プ電極上に熱圧着して接合させ、その後にＰｄ極細線を
外部リードへループを形成しながら導いて該リードに圧
着させ（ワイヤボンディング法）、或いは前記チップ上
に熱圧着したボールのネック部を切断してバンプ電極を
形成する如く使用される。EXAMPLE Pd extra fine wires are made of high-purity Pd containing rare earth elements (L
a, Ce, etc., elements with atomic numbers 57 to 71), Ge, B
Those to which base metals such as e, Hg, Si, Ca, and Al are added, more specifically, a Pd alloy having a composition of high-purity Pd (including inevitable impurities) and additional elements is melt cast, and then groove roll processing is performed. After performing the annealing process and annealing in the middle of the process, a bus bar having a wire diameter of 25 μm is formed by a wire drawing process, and after sufficient stress relief, it is wound on a spool and stored. This spool is mounted on a wire bonding machine, and when the bonding machine is used, the Pd ultrafine wire is fed to a capillary while being fed out, and the tip of the Pd ultrafine wire is discharge-heated by a spark to form the tip into a ball shape, This ball is thermocompression-bonded to the chip electrode of the semiconductor element by descending the capillary, and then the Pd ultrafine wire is guided to the external lead while forming a loop and pressure-bonded to the lead (wire bonding method). It is used to cut a neck portion of a ball thermocompression bonded onto a chip to form a bump electrode.
【０００９】本発明は、上記Ｐｄ極細線をその使用前に
水素を吸収させた状態にするものであり、水素を吸収さ
せる手段は次の通りである。 . 上記Ｐｄ極細線の製造工程中、Ｐｄ極細線を前記ス
プールに巻き取る工程の途中に常温の水素気流を収容し
たチャンバを配設し、このチャンバ内にＰｄ極細線を通
過させた後に前記スプールに巻き取らせる。 . 上記Ｐｄ極細線の製造工程が完了してスプールに巻
き取られたＰｄ極細線を、新たなスプールに移し換える
作業をし、その両スプール間に前記と同一のチャンバを
配設して、このチャンバ内にＰｄ極細線を通過させる。 . ワイヤボンディング機のスプール装着部とキャピラ
リーとの間のワイヤ繰出し経路に、常温の水素気流を収
容したチャンバを配設し、該チャンバ内にＰｄ極細線を
通過させてキャピラリーヘ導く。According to the present invention, the above Pd ultrafine wire is made to absorb hydrogen before its use. The means for absorbing hydrogen is as follows. In the process of manufacturing the Pd ultrafine wire, a chamber containing a hydrogen gas at room temperature is provided in the process of winding the Pd ultrafine wire on the spool, and the Pd ultrafine wire is passed through the chamber. Let it wind up. The Pd extra fine wire which has been wound on the spool after the manufacturing process of the Pd extra fine wire is completed is transferred to a new spool, and the same chamber as that described above is arranged between both spools. A Pd ultrafine wire is passed through the chamber. A chamber containing a hydrogen flow at room temperature is provided in the wire feeding path between the spool mounting portion of the wire bonding machine and the capillary, and the Pd ultrafine wire is passed through the chamber to guide it to the capillary.
【００１０】上記チャンバ内を通過するＰｄ極細線は、
チャンバ内で水素気流に接触して該極細線内に水素が含
浸吸収され水素吸収のＰｄ極細線が得られる。上記水素
の吸収手段において、その処理条件を例示すれば次の通
りである。上記吸収手段またはにおいて、 処理温度：２５℃ チャンバ内の水素濃度：
１atm チャンバ長さ：３０cm Ｐｄ極細線の通過速度：
１０cm／SEC また上記吸収手段においては、 処理温度：２５℃ チャンバ内の水素濃度：
１atm チャンバ長さ：５cm Ｐｄ極細線の通過速度：１
cm／SEC 尚、上記吸収手段またはにより作製したＰｄ極細線
は、吸収した水素濃度を低下させないために、Ｐｄ極細
線を巻き取ったスプールを水素収容のスプールケース内
に入れて保管することが好ましい。The Pd ultrafine wire passing through the chamber is
Upon contact with a hydrogen stream in the chamber, hydrogen is impregnated and absorbed in the ultrafine wire, and a Pd ultrafine wire for hydrogen absorption is obtained. The processing conditions of the hydrogen absorbing means are as follows. In the above-mentioned absorption means or, processing temperature: 25 ° C. Hydrogen concentration in chamber:
1atm Chamber length: 30cm Pd extra fine wire passage speed:
10 cm / SEC In the above absorption means, processing temperature: 25 ° C. Hydrogen concentration in chamber:
1 atm Chamber length: 5 cm Pd Extra fine wire passage speed: 1
cm / SEC It is preferable that the Pd extra fine wire produced by the above-mentioned absorption means or the above is stored by putting the spool wound with the Pd extra fine wire in a hydrogen containing spool case so as not to lower the absorbed hydrogen concentration. ..
【００１１】上記の如く水素が吸収された状態のＰｄ極
細線は、ワイヤボンディング機においてキャピラリーか
ら導出された先端部をスパーク等の放電により加熱して
ボールが形成され、前述の通りワイヤボンディング又は
バンプ形成のためにチップ電極上に熱圧着される。As described above, the Pd ultrafine wire in which hydrogen has been absorbed forms a ball by heating the tip of the capillary drawn out from the capillary by a discharge such as a spark in a wire bonding machine. It is thermocompression bonded onto the chip electrode for formation.
【００１２】本発明のテスト結果を比較品と共に表１に
示す。The test results of the present invention are shown in Table 1 together with the comparative product.
【００１３】[0013]
【表１】 [Table 1]
【００１４】各試料は、表１の組成からなる線径２５μ
ｍのＰｄ極細線であり、試料Ｎｏ．１〜８は水素を吸収
させた本発明実施品、試料Ｎｏ．９〜１６はＮｏ．１〜
８と同一組成で水素を吸収させない比較品である。上記
各試料をそれぞれ所定のサンプル数づつ放電加熱により
ボールを形成させ、それらのボール形状の真球度を測定
したものである。ボール形状の真球度は、放電時間を４
ｍｓとし、ボールの直径が線径の２．５倍となるように
放電々流を調整してボールを形成し、該ボールに歪が有
るか否かで測定した。測定の結果、歪が無い場合を○印
で、歪が有った場合を×印でそれぞれ表記した。Each sample has a wire diameter of 25 μ having the composition shown in Table 1.
m is a Pd extra fine wire, and the sample No. Samples Nos. 1 to 8 of the present invention in which hydrogen is absorbed are sample Nos. Nos. 9 to 16 are Nos. 1 to
It is a comparative product having the same composition as that of No. 8 and not absorbing hydrogen. Balls were formed by discharging a predetermined number of samples from each of the above samples, and the sphericity of the balls was measured. The ball-shaped sphericity requires a discharge time of 4
ms, and the discharge current was adjusted so that the diameter of the ball was 2.5 times the wire diameter to form a ball, and the ball was measured for distortion. As a result of the measurement, when there is no distortion, it is indicated by ◯, and when there is distortion, it is indicated by ×.
【００１５】従って、表１の測定結果により明らかな如
く、本発明実施品によればボール形成時のボール真球度
を高めることができ、ワイヤボンディング用またはバン
プ電極用として有用であることが確認できた。Therefore, as is clear from the measurement results in Table 1, it was confirmed that the balls of the present invention can enhance the sphericity of the balls during ball formation and are useful for wire bonding or bump electrodes. did it.
【００１６】[0016]
【効果】本発明によれば、ボール形成時におけるボール
形状の真球度を確保しながら卑金属の添加量を従来に較
べて増量させることができ、従って破断強度など機械的
強度および接合強度が共に改善され、信頼性の高い半導
体装置の作製に有用なＰｄ極細線を提供することができ
る。According to the present invention, it is possible to increase the addition amount of the base metal as compared with the conventional one while ensuring the sphericity of the ball shape at the time of ball formation, and therefore, the mechanical strength such as the breaking strength and the bonding strength are both improved. It is possible to provide a Pd extra fine wire which is improved and is useful for manufacturing a highly reliable semiconductor device.
【００１７】又、水素気流の雰囲気中でＰｄ極細線を放
電加熱してボール形成する方法に較べて、ボール形成時
に水素流れがないので酸化膜の生成を確実に防止し、ボ
ンディングの信頼性を向上させ得る。Further, compared with the method of forming balls by discharging and heating Pd ultrafine wires in an atmosphere of hydrogen flow, since there is no hydrogen flow during ball formation, the formation of an oxide film is reliably prevented and the reliability of bonding is improved. Can improve.
Claims (2)
させてなることを特徴とする半導体素子用のＰｄ極細
線。1. A Pd ultrafine wire for a semiconductor device, which is obtained by absorbing hydrogen in a Pd ultrafine wire containing a base metal.
させた状態にし、該Ｐｄ極細線を放電加熱してボールを
形成することを特徴とする半導体素子用のＰｄ極細線の
ボール形成方法。2. A method of forming a Pd ultrafine wire ball for a semiconductor device, comprising: forming a ball by causing Pd extrafine wire containing a base metal to absorb hydrogen and heating the Pd extrafine wire by discharge heating. ..
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3341321A JPH05175272A (en) | 1991-12-24 | 1991-12-24 | Pd superfine wire for semiconductor element use and method of forming ball consisting of that |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3341321A JPH05175272A (en) | 1991-12-24 | 1991-12-24 | Pd superfine wire for semiconductor element use and method of forming ball consisting of that |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05175272A true JPH05175272A (en) | 1993-07-13 |
Family
ID=18345159
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3341321A Pending JPH05175272A (en) | 1991-12-24 | 1991-12-24 | Pd superfine wire for semiconductor element use and method of forming ball consisting of that |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05175272A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010106851A1 (en) * | 2009-03-17 | 2010-09-23 | 新日鉄マテリアルズ株式会社 | Bonding wire for semiconductor |
| JP2013110494A (en) * | 2011-11-18 | 2013-06-06 | Toko Inc | Composite antenna |
-
1991
- 1991-12-24 JP JP3341321A patent/JPH05175272A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010106851A1 (en) * | 2009-03-17 | 2010-09-23 | 新日鉄マテリアルズ株式会社 | Bonding wire for semiconductor |
| JP4886899B2 (en) * | 2009-03-17 | 2012-02-29 | 新日鉄マテリアルズ株式会社 | Bonding wire for semiconductor |
| US8815019B2 (en) | 2009-03-17 | 2014-08-26 | Nippon Steel & Sumikin Materials., Ltd. | Bonding wire for semiconductor |
| JP2013110494A (en) * | 2011-11-18 | 2013-06-06 | Toko Inc | Composite antenna |
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