JP2018064050A - Copper alloy wire for ball bonding - Google Patents

Copper alloy wire for ball bonding Download PDF

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JP2018064050A
JP2018064050A JP2016202254A JP2016202254A JP2018064050A JP 2018064050 A JP2018064050 A JP 2018064050A JP 2016202254 A JP2016202254 A JP 2016202254A JP 2016202254 A JP2016202254 A JP 2016202254A JP 2018064050 A JP2018064050 A JP 2018064050A
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mass
wire
ball
bonding
copper
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JP6710141B2 (en
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満生 高田
Mitsuo Takada
満生 高田
裕之 天野
Hiroyuki Amano
裕之 天野
菜那子 前田
Nanako Maeda
菜那子 前田
祐佳 永江
Yuka Nagae
祐佳 永江
拓也 濱本
takuya Hamamoto
拓也 濱本
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Tanaka Denshi Kogyo KK
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Tanaka Denshi Kogyo KK
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Priority to TW105141377A priority patent/TWI738695B/en
Priority to CN201710200765.3A priority patent/CN107958890A/en
Priority to KR1020170044133A priority patent/KR102176359B1/en
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Abstract

PROBLEM TO BE SOLVED: To provide a copper alloy wire for ball bonding, which never causes a weld-bonding area of a compression-bonding ball to expand like a flower even if a bonding wire is thinned and molten balls are made smaller, and which allows a uniform compression form to be ensured with stability.SOLUTION: A copper alloy wire for ball bonding according to the present invention comprises 0.1-1.5 mass% of nickel (Ni), 0.01-1.5 mass% of platinum (Pt) or palladium (Pd), 0.1-20 mass ppm of sulfur (S), 10-80 mass ppm of oxygen (O) and the balance consisting of copper (Cu). Particularly, the copper alloy wire for ball bonding comprises 0.1-1.5 mass% of nickel (Ni), 0.01-1.5 mass% of platinum (Pt) or palladium (Pd), 0.1-20 mass ppm of sulfur (S), 10-100 mass ppm of phosphorus (P), 10-80 mass ppm of oxygen (O) and the balance consisting of copper (Cu).SELECTED DRAWING: None

Description

本発明は、ボールボンディング用銅合金線に関し、特にフリーエアボール（ＦＡＢ）ボンディングにより半導体素子上のパッド電極に第一ボンドをした後、ステッチボンディングにより、リードフレーム上の外部電極に第二ボンドをするボールボンディング用銅合金線の第一ボンドの改良に関するものである。 The present invention relates to a copper alloy wire for ball bonding, and in particular, after a first bond is made to a pad electrode on a semiconductor element by free air ball (FAB) bonding, a second bond is made to an external electrode on a lead frame by stitch bonding. This invention relates to the improvement of the first bond of the copper alloy wire for ball bonding.

これまで銅ニッケル等合金は、ボンディングワイヤとしてほとんど考慮されていなかった。ニッケル（Ｎｉ）、あるいは、白金（Ｐｔ）またはパラジウム（Ｐｄ）を添加すると銅（Ｃｕ）の抵抗が上昇する。このため、銅ニッケル等合金をボンディングワイヤにすると、金ボンディングワイヤの代替品として低抵抗を特徴とした銅ボンディングワイヤの優位性が失われてしまうという欠点がある。銅ニッケル等合金に関するボンディングワイヤを例示すると以下のものがある。 Until now, alloys such as copper nickel have hardly been considered as bonding wires. When nickel (Ni), platinum (Pt) or palladium (Pd) is added, the resistance of copper (Cu) increases. For this reason, when an alloy such as copper nickel is used as the bonding wire, there is a disadvantage that the superiority of the copper bonding wire characterized by low resistance is lost as an alternative to the gold bonding wire. Examples of bonding wires related to alloys such as copper nickel include the following.

特開平０１−２９１４３５号公報（後述する特許文献１）の特許請求の範囲（１）に「Ｓ、ＳｅおよびＴｅの総含有量を１．０ｐｐｍ以下とした高純度無酸素銅に、Ａｌ、Ｃｒ、Ｆｅ、Ｍｎ、Ｎｉ、Ｐ、Ｓｎ、Ｚｎの１種または２種以上を総計で１．０〜５００ｐｐｍ添加したことを特徴とする半導体装置用銅合金極細線」からなる発明が開示され、第１表の実施例６に、高純度無酸素銅にＮｉ：３７６ｐｐｍを添加した素材からなる半導体装置用銅合金極細線が開示されている。 In claim (1) of Japanese Patent Laid-Open No. 01-291435 (Patent Document 1 described later), “High purity oxygen-free copper having a total content of S, Se, and Te of 1.0 ppm or less, Al, Cr , Fe, Mn, Ni, P, Sn, Zn, or a total of 1.0 to 500 ppm of one or more of Zn added to the semiconductor device, the invention comprising " Example 6 in Table 1 discloses a copper alloy ultrafine wire for a semiconductor device made of a material obtained by adding Ni: 376 ppm to high-purity oxygen-free copper.

また、特開平０１−２９０２３１号公報（後述する特許文献２）の特許請求の範囲（２）項には、「Ｓ、ＳｅおよびＴｅの総含有量を１．０ｐｐｍ以下とした高純度無酸素銅に、少なくともＳｉを１．０ｐｐｍ添加し、さらにＡｌ、Ｃｒ、Ｆｅ、Ｍｎ、Ｎｉ、Ｐ、Ｓｎ、Ｚｎの１種または２種以上をＳｉと総計で１．０〜５００ｐｐｍ添加したことを特徴とする半導体装置用銅合金極細線」からなる発明が開示され、第２表の実施例９に、純度無酸素銅にＳｉ：５４ｐｐｍおよびＮｉ：４６ｐｐｍを添加したことを特徴とする半導体装置用銅合金極細線」が開示されている。 Further, in claim (2) of Japanese Patent Laid-Open No. 01-290231 (Patent Document 2 described later), “high purity oxygen-free copper having a total content of S, Se and Te of 1.0 ppm or less” Further, at least 1.0 ppm of Si is added, and one or more of Al, Cr, Fe, Mn, Ni, P, Sn, and Zn are added in a total amount of 1.0 to 500 ppm with Si. A copper alloy for a semiconductor device, characterized in that Si: 54 ppm and Ni: 46 ppm were added to pure oxygen-free copper in Example 9 of Table 2. "Extra fine wire" is disclosed.

しかしながら、同公報の第２表の比較例２では、高純度無酸素銅にＳｉ：８９ｐｐｍおよびＮｉ：６６０ｐｐｍを添加した素材は、ボール硬度が高くなり、被膜の損傷やマイクロクラックを回避できなかったことが記載されている。これは、ニッケル（Ｎｉ）の濃度が高くなると、表層における銅（Ｃｕ）マトリックス中で固溶したニッケル（Ｎｉ）が大気中の酸素と結びついて酸化ニッケル粒子を形成したためと考えられる。よって、この比較例２の素材を半導体装置用ボンディングワイヤに適用した場合、銅合金極細線として高温下で使用することができないことを示している。 However, in Comparative Example 2 in Table 2 of the same publication, a material obtained by adding Si: 89 ppm and Ni: 660 ppm to high-purity oxygen-free copper has high ball hardness, and damage to the coating and microcracks cannot be avoided. It is described. This is presumably because when the concentration of nickel (Ni) increases, nickel (Ni) dissolved in the copper (Cu) matrix in the surface layer is combined with oxygen in the atmosphere to form nickel oxide particles. Therefore, when the raw material of this comparative example 2 is applied to the bonding wire for semiconductor devices, it shows that it cannot be used at a high temperature as a copper alloy fine wire.

このような状況下で本出願人は、特開２０１４−１６５２７２号公報（ｄ３）に係る発明「断面減少率９９％以上で連続伸線され、表層と内部酸化層及び銅稀薄ニッケル合金層とから構成される半導体装置接合用銅ニッケル希薄合金ワイヤにおいて、上記表層は酸化物の成長層からなり、上記内部酸化層は金属不足型酸化銅マトリックスに酸化ニッケル粒子が微細に分散した層からなり、上記銅稀薄ニッケル合金層は純度９９．９９５質量％以上の銅（Ｃｕ）マトリックスに０．１〜１．５質量％のニッケル（Ｎｉ）が均一固溶した合金層であって、上記表面層の厚さに対する上記内部酸化層の厚さが６０倍以上である、ことを特徴とする半導体装置接合用銅稀薄ニッケル合金ワイヤの構造」を開示した。これは、銅（Ｃｕ）マトリックス中の酸素を固溶したニッケル（Ｎｉ）が固定することおよび銅稀薄ニッケル合金の表面層に純銅層が形成されやすくなることを利用しようとしたものである。 Under such circumstances, the applicant of the invention according to Japanese Patent Application Laid-Open No. 2014-165272 (d3) “from the surface layer, the internal oxide layer, and the copper dilute nickel alloy layer continuously drawn with a cross-section reduction rate of 99% or more. In the copper-nickel diluted alloy wire for joining a semiconductor device, the surface layer is composed of an oxide growth layer, and the internal oxide layer is composed of a layer in which nickel oxide particles are finely dispersed in a metal-deficient copper oxide matrix, The copper dilute nickel alloy layer is an alloy layer in which 0.1 to 1.5% by mass of nickel (Ni) is homogeneously dissolved in a copper (Cu) matrix having a purity of 99.995% by mass or more, and the thickness of the surface layer is The structure of the copper dilute nickel alloy wire for joining a semiconductor device, wherein the thickness of the internal oxide layer with respect to the thickness is 60 times or more is disclosed. This is to utilize the fact that nickel (Ni) in which oxygen in a copper (Cu) matrix is dissolved is fixed, and that a pure copper layer is easily formed on the surface layer of a copper dilute nickel alloy.

その結果、このボンディングワイヤは、表層のＣｕ２Ｏ膜が周囲温度で成長するよりもはるかに速く、金属不足型銅酸化物（Ｃｕ２−ｘＯ）マトリックス中のフリーの酸素がＣｕ２−ｘＯマトリックス中をすばやく移動できる。よって、金属不足型銅酸化物（Ｃｕ２−ｘＯ）マトリックスがクッション層として働き、表層の半球状の酸化膜模様の形成が無くなり、表層のＣｕ２Ｏ膜が安定する。このため、このボンディングワイヤは、均一な再結晶組織が得られ、ワイヤが蛇行したり、リーニングしたりすることはない。すなわち、これまで溶融ボールが不規則に拡がるのは、リーニングと称されるボンディングワイヤの屈曲や折れ曲がりなどが解消された。また、第二ボンドにおけるボンディングワイヤのステッチ接合性も向上するなどの効果が得られる。 As a result, the bonding wire is much faster than the surface Cu 2 O film grows at ambient temperature, and the free oxygen in the metal-deficient copper oxide (Cu 2-x O) matrix becomes Cu 2 -x. Move quickly through the O matrix. Therefore, the metal-deficient copper oxide (Cu 2−x O) matrix functions as a cushion layer, the formation of a hemispherical oxide film pattern on the surface layer is eliminated, and the surface Cu 2 O film is stabilized. For this reason, this bonding wire has a uniform recrystallized structure, and the wire does not meander or lean. In other words, the irregular expansion of the molten ball so far has eliminated the bending or bending of the bonding wire, which is called leaning. Moreover, the effect of improving the stitch bondability of the bonding wire in the second bond can be obtained.

しかしながら、例示した銅ニッケル希薄合金のボンディングワイヤには、いずれもワイヤ表面上に不安定な酸化膜が形成されやすいという致命的な欠陥がある。このためこれまでの銅ニッケル希薄合金ワイヤを長期間放置すると、ワイヤ表面の酸素濃度が増加してワイヤに不安定な酸化物が増殖される。このようなボンディングワイヤにフリーエアボール（ＦＡＢ）方式で溶融ボールを形成し、アルミパッドに鉛直方向から溶融ボールを押圧しても圧着ボールが円盤状に広がらず、圧着ボールの外延部がいびつな花びら状の形状で凝固する傾向があった。 However, each of the exemplified copper nickel diluted alloy bonding wires has a fatal defect that an unstable oxide film is easily formed on the wire surface. For this reason, when the copper-nickel diluted alloy wire so far is left for a long period of time, the oxygen concentration on the surface of the wire increases and an unstable oxide grows on the wire. Even if a molten ball is formed on such a bonding wire by a free air ball (FAB) method, and the molten ball is pressed against the aluminum pad from the vertical direction, the bonded ball does not spread in a disk shape, and the extended portion of the pressed ball is irregular. There was a tendency to coagulate in a petal-like shape.

ここで、アルミパッドとは、純アルミニウム（Ａｌ）またはアルミニウム（Ａｌ）が主成分の合金からなるパッド電極のことである。また、花びら状という表現は、図５に示すように、圧着ボールの中心とワイヤの軸中心とが一致しているものの、圧着ボールの外延部の形状が円形でない状態をいう。すなわち、圧着ボールが花びら状になる現象は、溶融ボールが作製された段階では発生せずに、溶融ボールをアルミパッドに対して鉛直方向から押圧する段階で圧着ボールに現れる異常な形状である。花びら状の計測手段は後述する。 Here, the aluminum pad is a pad electrode made of pure aluminum (Al) or an alloy containing aluminum (Al) as a main component. In addition, the expression petal-like refers to a state where the center of the press-bonded ball and the axis center of the wire coincide with each other but the shape of the outer extension of the press-bonded ball is not circular as shown in FIG. In other words, the phenomenon that the pressure-bonded ball becomes a petal shape is an abnormal shape that does not occur at the stage where the molten ball is produced but appears on the pressure-bonded ball when the molten ball is pressed against the aluminum pad from the vertical direction. The petal-shaped measuring means will be described later.

この花びら状という現象は、これまでのリーニング等による凹部の花弁状欠陥（特開２００７−２８４７８７号公報の図１参照）、あるいは、歪んだ円形の圧着ボール（特開２００７−２６６３３９号公報の図２参照）のような状態をいうのではない。花弁状欠陥は、被覆層と芯材との界面構造に起因してボール接合部の最外周近傍が花弁状に凹凸変形を起こし、真円性からずれるものである。この花弁状欠陥は被覆層を有するボンディングワイヤにみられる現象であり、アルミパッド上の溶融ボールの濡れ性に起因する現象である。また、歪んだ円形の圧着ボールは、ワイヤ先端に形成したボール部がワイヤ軸に対し非対称に形成される現象であり、溶融ボールが形成された段階ですでに偏心している。さらに、リーニングは、ボンディングされたワイヤの第一ボンド付近において、鉛直方向から観察して再結晶領域（ＨＡＺ）と呼ばれる箇所で横方向に倒れるように曲がる現象である。このような偏心ボールが形成されたボンディングワイヤをアルミパッドに対して鉛直方向から押圧すると、後述するように、歪んだ円形の圧着ボールを一般的な顕微鏡下で観察することができる。これらの偏心ボールの一例を図７に示す。 This petal-like phenomenon is caused by the petal-like defect of the concave portion due to the conventional leaning or the like (see FIG. 1 of Japanese Patent Laid-Open No. 2007-284787), or a distorted circular pressure-bonded ball (see Japanese Patent Laid-Open No. 2007-266339). It does not mean a state like (see 2). The petal-like defect is caused by irregular deformation in the vicinity of the outermost periphery of the ball joint portion due to the interface structure between the coating layer and the core material, and deviates from roundness. This petal-like defect is a phenomenon observed in the bonding wire having the coating layer, and is a phenomenon caused by the wettability of the molten ball on the aluminum pad. Further, the distorted circular pressure-bonded ball is a phenomenon in which the ball portion formed at the tip of the wire is formed asymmetrically with respect to the wire axis, and is already eccentric when the molten ball is formed. Further, the leaning is a phenomenon in which, in the vicinity of the first bond of the bonded wire, the wire is bent so as to fall laterally at a place called a recrystallization region (HAZ) when observed from the vertical direction. When the bonding wire on which such an eccentric ball is formed is pressed against the aluminum pad from the vertical direction, the distorted circular pressure-bonded ball can be observed under a general microscope as will be described later. An example of these eccentric balls is shown in FIG.

偏心ボールでも歪んだ圧着ボールが発生すると、それを考慮してアルミパッドの圧着面積が大きくならざるを得ない。このため、これまではアルミパッドの単位面積当たりのボンディングワイヤの密集度を高くできないという欠点があった。また、偏心により圧着ボールがアルミパッドからはみ出すかどうかにかかわらず、近年の実装工程ではボンディングワイヤの集積密度がますます高まってきた。そのためボンディングワイヤの密集度を高めようとすると、第一ボンド工程において圧着ボールが、図５に示すように花びら状に変形するという現象そのものが許容されなくなってきた。 If a distorted press-bonded ball is generated even with an eccentric ball, the press-bonded area of the aluminum pad must be increased in consideration of this. For this reason, there has been a drawback that the density of bonding wires per unit area of the aluminum pad cannot be increased so far. In addition, the integration density of bonding wires has increased more and more in recent mounting processes, regardless of whether or not the crimp ball protrudes from the aluminum pad due to eccentricity. Therefore, in order to increase the density of the bonding wires, the phenomenon itself that the pressure-bonded ball is deformed into a petal shape as shown in FIG. 5 in the first bonding process has become unacceptable.

この花びら状という現象は、無垢のボンディングワイヤにあってこれまでまったく考慮されてこなかった課題である。「花びら状」という現象は銅合金の結晶構造に起因する。すなわち、花びら状現象は、溶融ボールが凝固する際、凝固組織の不均一さに起因して圧着ボールが等方的に凝固しない問題である。そのため、「花びら状」現象には、後述する実施例および比較例に示すように様々なものがあり、溶融ボールがキャピラリによって圧着され、凝固する際にこの「花びら状」現象がみられる。この原因は定かではないが、凝固組織の不均一さが関与しており、その結果、アルミパッドと圧着ボールの界面状態が不均質になるのである。「花びら状」現象がみられると、実装工程が安定しないので、実装工程で許容されなくなる。 This phenomenon of petals is a problem that has not been considered at all in the case of solid bonding wires. The phenomenon of “petal” is due to the crystal structure of the copper alloy. That is, the petal-like phenomenon is a problem that when the molten ball is solidified, the press-bonded ball is not solidified isotropically due to non-uniformity of the solidified structure. Therefore, there are various “petal-like” phenomena as shown in Examples and Comparative Examples described later, and this “petal-like” phenomenon is observed when a molten ball is pressed and solidified by a capillary. Although this cause is not certain, non-uniformity of the solidified structure is involved, and as a result, the interface state between the aluminum pad and the press-bonded ball becomes non-uniform. If the “petal” phenomenon is observed, the mounting process is not stable, and is not allowed in the mounting process.

他方、本発明の銅合金線のボンディングワイヤを製造するにはこれまでのいくつかの製造方法を適宜利用することができる。
たとえば、特開昭５９−１５５１６１号公報の実施例には、「まず無酸素銅を用いて直径０．１３ｍｍの素材ワイヤを製造する。…（中略）…このようにして得られた金メッキワイヤを、引抜加工によって直径０．０２５ｍｍに仕上げる。必要に応じて約３５０度Ｃで焼鈍を行う」ことが示されている。 On the other hand, in order to manufacture the copper alloy wire bonding wire of the present invention, several conventional manufacturing methods can be appropriately used.
For example, in the example of Japanese Patent Application Laid-Open No. 59-155161, “First, a material wire having a diameter of 0.13 mm is manufactured using oxygen-free copper. It is finished by drawing to a diameter of 0.025 mm. Annealing is performed at about 350 ° C. as necessary. ”

同様に、特開平０３−１３５０４１号公報の特許請求の範囲第１項には、「導体の表面に、合金元素あるいは高濃度合金を蒸着、メッキにより被覆した後、拡散熱処理を施すことにより合金化を行ない、その後伸線することを特徴とする半導体用ボンディング細線の製造方法」の発明が示されている。 Similarly, in claim 1 of Japanese Patent Laid-Open No. 03-135041, “alloying is performed by depositing an alloy element or high-concentration alloy on the surface of the conductor by vapor deposition and plating, and then performing diffusion heat treatment. The invention of “a manufacturing method of a bonding fine wire for a semiconductor characterized in that the wire is drawn and then drawn” is shown.

また、特開昭６４−００３９０３号公報の特許請求の範囲第（３）項には、所定のＣｕ合金の鋳塊に、「熱間圧延を施し、その後伸線加工と少なくとも１回以上中間焼鈍を繰返して所定の線径に仕上げ、しかる後非酸化性又は還元性雰囲気下で焼鈍することにより、所望の機械的特性とすることを特徴とする電子機器用銅細線の製造法」の発明が示されている。 Further, in claim (3) of Japanese Patent Application Laid-Open No. 64-003903, a predetermined Cu alloy ingot is subjected to “hot rolling and then wire drawing and intermediate annealing at least once. The invention of `` a method for producing a copper fine wire for electronic equipment, characterized in that the desired mechanical properties are obtained by repeating the above to finish to a predetermined wire diameter and then annealing in a non-oxidizing or reducing atmosphere '' It is shown.

同様に、特開平１１−２９３４３１号公報の請求項１には、「晶出物などの異相を含む銅合金軟質素材を冷間加工し、必要に応じて中間焼鈍を施す、線径５０μｍ以下の銅合金極細線の製造方法であって、前記銅合金軟質素材からの冷間加工率を９９．９９９％以下とし、中間焼鈍を施す場合は、中間焼鈍と中間焼鈍の間の冷間加工率は９９．９９９％以下とし、最終中間焼鈍後の冷間加工率は８０〜９９％にすることを特徴とする銅合金銅細線の製造方法」の発明が示されている。 Similarly, in claim 1 of Japanese Patent Laid-Open No. 11-293431, “a copper alloy soft material containing a heterogeneous phase such as a crystallized material is cold-worked and subjected to an intermediate annealing as necessary. The wire diameter is 50 μm or less. A method of manufacturing a copper alloy ultrafine wire, wherein the cold working rate from the copper alloy soft material is 99.999% or less, and when performing the intermediate annealing, the cold working rate between the intermediate annealing and the intermediate annealing is The invention of "a method for producing a copper alloy copper fine wire characterized in that 99.999% or less and the cold working rate after the final intermediate annealing is 80 to 99%" is shown.

特開平０１−２９１４３５号公報Japanese Patent Laid-Open No. 01-291435 特開平０１−２９０２３１号公報JP-A-01-290231 特開２０１４−１６５２７２号公報JP 2014-165272 A

本発明者等は、銅合金線ボンディングワイヤの花びら状現象を注意深く観察し、このような花びら状に拡がる現象は、製造直後のボンディングワイヤで観察されず、数か月放置したボンディングワイヤでみられたことに気が付いた。他方、無垢の純銅線の場合には、製造直後でも同様にボンディングワイヤの圧着ボールが花びら状に拡がることがあった。そこで、本発明者等は、圧着ボールが花びら状に拡がらない合金組成を種々探索し、さらに研究を進めて本発明を完成させるに至った。 The present inventors carefully observed the petal-like phenomenon of copper alloy wire bonding wire, and such a phenomenon spreading to a petal shape was not observed with the bonding wire immediately after manufacture, but was observed with the bonding wire left for several months. I realized that. On the other hand, in the case of pure pure copper wire, the bonding ball of the bonding wire may spread like a petal in the same manner immediately after manufacture. Accordingly, the present inventors have searched for various alloy compositions in which the press-bonded balls do not spread in the shape of petals, and have further advanced research to complete the present invention.

本発明の目的は、ボンディングワイヤを細くして溶融ボールを小さくしても、圧着ボールが花びら状に拡がらず、安定して均一な圧着形状を確保することができるボールボンディング用銅合金線を提供することにある。 An object of the present invention is to provide a copper alloy wire for ball bonding that can secure a stable and uniform crimped shape, even if the bonding wire is thinned and the molten ball is made smaller, and the crimped ball does not expand into a petal shape. It is to provide.

本発明のボールボンディング用銅合金線の一つは、ボールボンディング用銅希薄合金において、０．１〜１．５質量％のニッケル（Ｎｉ）、０．０１〜１．５質量％の白金（Ｐｔ）またはパラジウム（Ｐｄ）のうちのいずれか１種以上を合計で０．０１〜１．５質量％、更に０．１〜２０質量ｐｐｍのイオウ（Ｓ）、１０〜８０質量ｐｐｍの酸素（Ｏ）および残部銅（Ｃｕ）からなることを特徴とする。 One of the copper alloy wires for ball bonding of the present invention is a dilute copper alloy for ball bonding in which 0.1 to 1.5 mass% nickel (Ni), 0.01 to 1.5 mass% platinum (Pt ) Or palladium (Pd) in a total of 0.01 to 1.5 mass%, further 0.1 to 20 mass ppm of sulfur (S), 10 to 80 mass ppm of oxygen (O ) And the balance copper (Cu).

また、本発明のボールボンディング用銅合金線の他の一つは、０．１〜１．５質量％のニッケル（Ｎｉ）、０．０１〜１．５質量％の白金（Ｐｔ）またはパラジウム（Ｐｄ）のうちのいずれか１種以上を合計で０．０１〜１．５質量％、更に１０〜１００質量ｐｐｍのリン（Ｐ）、１０〜８０質量ｐｐｍの酸素（Ｏ）および残部銅（Ｃｕ）からなることを特徴とする。 Further, another one of the copper alloy wires for ball bonding of the present invention is 0.1 to 1.5% by mass of nickel (Ni), 0.01 to 1.5% by mass of platinum (Pt) or palladium ( Any one or more of Pd) are 0.01 to 1.5 mass% in total, further 10 to 100 mass ppm of phosphorus (P), 10 to 80 mass ppm of oxygen (O), and the balance copper (Cu). ).

また、本発明のボールボンディング用銅合金線の他の一つは、０．１〜１．５質量％のニッケル（Ｎｉ）、０．０１〜１．５質量％の白金（Ｐｔ）またはパラジウム（Ｐｄ）のうちのいずれか１種以上を合計で０．０１〜１．５質量％、更に０．１〜２０質量ｐｐｍのイオウ（Ｓ）、１０〜１００質量ｐｐｍのリン（Ｐ）、１０〜８０質量ｐｐｍの酸素（Ｏ）および残部銅（Ｃｕ）からなることを特徴とする。 Further, another one of the copper alloy wires for ball bonding of the present invention is 0.1 to 1.5% by mass of nickel (Ni), 0.01 to 1.5% by mass of platinum (Pt) or palladium ( Any one or more of Pd) in a total of 0.01 to 1.5 mass%, further 0.1 to 20 mass ppm of sulfur (S), 10 to 100 mass ppm of phosphorus (P), 10 to 10 mass ppm. It consists of 80 mass ppm of oxygen (O) and the balance copper (Cu).

本発明の実施態様は以下のとおりである。すなわち、上記ニッケル（Ｎｉ）の含有量が０．２〜１．２質量％であることが好ましい。より好ましくは、０．５〜１．０質量％の範囲である。また、上記白金（Ｐｔ）またはパラジウム（Ｐｄ）の含有量が０．０５〜０．８質量％であることが好ましい。そして、白金（Ｐｔ）またはパラジウム（Ｐｄ）よりもニッケル（Ｎｉ）からなる銅希薄合金が好ましい。特にニッケル（Ｎｉ）および白金（Ｐｔ）またはパラジウム（Ｐｄ）からなる銅希薄合金がより好ましい。また、上記イオウ（Ｓ）の含有量が２〜１０質量ｐｐｍであることが好ましい。 Embodiments of the present invention are as follows. That is, the nickel (Ni) content is preferably 0.2 to 1.2% by mass. More preferably, it is the range of 0.5-1.0 mass%. Moreover, it is preferable that content of the said platinum (Pt) or palladium (Pd) is 0.05-0.8 mass%. A copper dilute alloy made of nickel (Ni) is more preferable than platinum (Pt) or palladium (Pd). In particular, a copper dilute alloy made of nickel (Ni) and platinum (Pt) or palladium (Pd) is more preferable. Moreover, it is preferable that content of the said sulfur (S) is 2-10 mass ppm.

本発明において、銅マトリックスに０．１〜１．５質量％のニッケル（Ｎｉ）、０．０１〜１．５質量％の白金（Ｐｔ）またはパラジウム（Ｐｄ）のうちのいずれか１種以上を合計で０．０１〜１．５質量％含有させるのは、これらの含有合金成分が銅マトリックスに完全に均一固溶するからである。また、ニッケル（Ｎｉ）等の含有合金成分は銅マトリックス中に存在する酸素を固定する作用を示すからである。また、この範囲内であれば、銅合金線ワイヤの表面に銅（Ｃｕ）の含有量が高い表面偏析層が生じることはない。 In this invention, 0.1-1.5 mass% nickel (Ni), 0.01-1.5 mass% platinum (Pt), or any one of palladium (Pd) is added to a copper matrix. The reason why the total content is 0.01 to 1.5% by mass is that these alloy components are completely and uniformly dissolved in the copper matrix. Moreover, it is because containing alloy components, such as nickel (Ni), show the effect | action which fixes the oxygen which exists in a copper matrix. Moreover, if it exists in this range, the surface segregation layer with high content of copper (Cu) will not arise on the surface of a copper alloy wire.

ニッケル（Ｎｉ）の含有量の下限値を０．１質量％とし、白金（Ｐｔ）またはパラジウム（Ｐｄ）の下限値を０．０１質量％としたのは、この下限値未満では結晶粒が粗大化し圧着時に局所的に変形してしまうからである。他方、ニッケル（Ｎｉ）等のうちのいずれか１種以上の上限値を合計で１．５質量％としたのは、この上限値を超えると、圧着ボールが硬くなりすぎてチップダメージを起こすからである。ニッケル（Ｎｉ）の含有量が０．２〜１．２質量％であり、白金（Ｐｔ）またはパラジウム（Ｐｄ）の含有量が０．０５〜０．８質量％であれば、圧着ボールの結晶粒径がある程度均一な大きさになり、安定した円盤状の圧着ボールが得られる。銅合金の圧着ボール形状に関しては白金（Ｐｔ）またはパラジウム（Ｐｄ）よりもニッケル（Ｎｉ）のほうが、作用効果が大きい。ニッケル（Ｎｉ）の含有量が０．５〜１．０質量％の範囲が特に好ましい。 The lower limit value of the nickel (Ni) content is 0.1% by mass, and the lower limit value of platinum (Pt) or palladium (Pd) is 0.01% by mass. This is because it is locally deformed during compression bonding. On the other hand, the reason why the upper limit value of any one or more of nickel (Ni) or the like is set to 1.5% by mass is that if this upper limit value is exceeded, the press-bonded ball becomes too hard and causes chip damage. It is. If the content of nickel (Ni) is 0.2 to 1.2% by mass and the content of platinum (Pt) or palladium (Pd) is 0.05 to 0.8% by mass, the crystals of the press-bonded ball The particle size becomes uniform to some extent, and a stable disk-shaped press-bonded ball can be obtained. With regard to the shape of the copper alloy press-bonded ball, nickel (Ni) has a larger effect than platinum (Pt) or palladium (Pd). The content of nickel (Ni) is particularly preferably in the range of 0.5 to 1.0% by mass.

本発明の銅合金線ワイヤに０．１〜２０質量ｐｐｍのイオウ（Ｓ）を含有させると、意外にも酸素の侵入を止める効果のあることが分かった。これまでイオウ（Ｓ）は溶融した銅ボールを硬くするので、添加元素から排除されていた元素である。０．１〜２０質量ｐｐｍのイオウ（Ｓ）は銅合金線ワイヤの表面層を支配して表面希薄層をつくることもない。 It has been found that when 0.1 to 20 ppm by mass of sulfur (S) is contained in the copper alloy wire of the present invention, it is surprisingly effective to stop oxygen from entering. So far, sulfur (S) is an element that has been excluded from the additive elements because it hardens the molten copper ball. 0.1 to 20 ppm by mass of sulfur (S) does not dominate the surface layer of the copper alloy wire and does not form a surface dilute layer.

イオウ（Ｓ）が０．１質量ｐｐｍ以上あると銅合金線の表面層を支配し、酸素の侵入を止めることができる。他方、イオウ（Ｓ）が２０質量ｐｐｍを超えると、圧着ボールが硬くなりすぎ、ボールボンディングするとアルミスプラッシュを起こす。よって、イオウ（Ｓ）の含有量を０．１〜２０質量ｐｐｍとした。イオウ（Ｓ）は銅合金線ワイヤに及ぼす影響力が強いので、イオウ（Ｓ）の含有量は２〜１０質量ｐｐｍであることが好ましい。 When sulfur (S) is 0.1 mass ppm or more, the surface layer of the copper alloy wire is controlled, and the intrusion of oxygen can be stopped. On the other hand, when sulfur (S) exceeds 20 ppm by mass, the press-bonded ball becomes too hard, and aluminum splash occurs when the ball is bonded. Therefore, the content of sulfur (S) was set to 0.1 to 20 mass ppm. Since sulfur (S) has a strong influence on the copper alloy wire, the content of sulfur (S) is preferably 2 to 10 ppm by mass.

本発明の銅合金線ワイヤが大気中で長期保存に耐えるには、ワイヤ中にある程度の酸素量が必要である。本発明の銅合金線ワイヤに１０〜８０質量ｐｐｍの酸素（Ｏ）を含有させておくと、圧着ボール形状が安定する効果のあることが分かった。ニッケル酸化物等が銅マトリックス中に固定され、この酸化物粒子のピン止め効果によって圧着ボールの結晶粒径がある程度の均一な大きさに保たれるからである。酸素（Ｏ）が下限値未満であればこのような抑制効果はなくなる。また、酸素（Ｏ）が上限値を超えると、第２接合点（ボンディングワイヤとリードフレームや基板などとの接合点）において接合性が低下するため、接合不良や実装工程での歩留まり低下が発生する。よって、ボンディングワイヤとして使用する際の酸素（Ｏ）の含有量を１０〜８０質量ｐｐｍとした。 In order for the copper alloy wire of the present invention to withstand long-term storage in the atmosphere, a certain amount of oxygen is required in the wire. It has been found that when 10 to 80 ppm by mass of oxygen (O) is contained in the copper alloy wire of the present invention, the shape of the press-bonded ball is stable. This is because nickel oxide or the like is fixed in the copper matrix, and the crystal grain size of the press-bonded ball is kept to a certain level by the pinning effect of the oxide particles. If oxygen (O) is less than the lower limit, such a suppression effect is lost. Also, if oxygen (O) exceeds the upper limit value, the bondability at the second bonding point (the bonding point between the bonding wire and the lead frame, the substrate, etc.) decreases, resulting in poor bonding and a decrease in yield in the mounting process. To do. Therefore, the content of oxygen (O) when used as a bonding wire is 10 to 80 ppm by mass.

特にニッケル（Ｎｉ）は酸素（Ｏ）と酸化物を形成して銅（Ｃｕ）マトリックス中に固定されるので、ピン止め効果が大きくなる。ただし、酸素（Ｏ）は銅マトリックスを透過するので、通常の銅合金線においては、ニッケル（Ｎｉ）などが酸化ニッケル等になる分だけ酸素を含有することができる。しかしながら、酸化ニッケル等の酸化物になると、この体積膨張が呼び水となって大気中から銅マトリックスへ酸素が侵入しやすくなる。そこで、所定量のイオウ（Ｓ）またはリン（Ｐ）を添加することによって酸素（Ｏ）の侵入を抑制することにした。すなわち、所定量のイオウ（Ｓ）またはリン（Ｐ）を添加することによって数か月放置しても本発明の銅合金線ワイヤに含まれる酸素（Ｏ）の含有量があまり増加しない効果がある。 Particularly, since nickel (Ni) forms an oxide with oxygen (O) and is fixed in the copper (Cu) matrix, the pinning effect is increased. However, since oxygen (O) permeates through the copper matrix, an ordinary copper alloy wire can contain oxygen as much as nickel (Ni) or the like becomes nickel oxide or the like. However, when it becomes an oxide such as nickel oxide, this volume expansion becomes priming water, and oxygen easily enters the copper matrix from the atmosphere. Therefore, the invasion of oxygen (O) was suppressed by adding a predetermined amount of sulfur (S) or phosphorus (P). That is, there is an effect that the content of oxygen (O) contained in the copper alloy wire of the present invention does not increase so much even if left for several months by adding a predetermined amount of sulfur (S) or phosphorus (P). .

本発明において１０〜１００質量ｐｐｍのリン（Ｐ）は、銅合金線ワイヤを酸化させない効果のほかに、溶融ボールを形成したときにフラックス作用を示してワイヤ表面の酸化膜を除去する効果がある。リン（Ｐ）が下限値の１０質量ｐｐｍ未満では上記効果がない。また、リン（Ｐ）が上限値の１００質量ｐｐｍを超えると、アルミパッド上でアルミスプラッシュを起こす。よって、リン（Ｐ）の範囲を１０〜１００質量ｐｐｍとした。 In the present invention, 10 to 100 ppm by mass of phosphorus (P) has the effect of removing the oxide film on the surface of the wire by exhibiting the flux action when the molten ball is formed in addition to the effect of not oxidizing the copper alloy wire. . If phosphorus (P) is less than the lower limit of 10 ppm by mass, the above effect is not obtained. Moreover, when phosphorus (P) exceeds the upper limit of 100 mass ppm, aluminum splash is caused on the aluminum pad. Therefore, the range of phosphorus (P) was set to 10 to 100 ppm by mass.

本発明の銅合金線細線において、素材となる高純度銅（Ｃｕ）の純度は９９．９９質量％以上あればよい。リン脱酸銅や無酸素銅を用いることができる。残りの０．０１質量％未満には、銀（Ａｇ）や鉄（Ｆｅ）が代表的に含まれる。その他、鉛（Ｐｂ）、スズ（Ｓｎ）、アンチモン（Ｓｂ）、ヒ素（Ａｓ）、ビスマス（Ｂｉ）、クロム（Ｃｒ）、テルル（Ｔｅ）、セレン（Ｓｅ）、シリコン（Ｓｉ）などが含まれる。 In the copper alloy thin wire of the present invention, the purity of the high-purity copper (Cu) used as a material may be 99.99% by mass or more. Phosphorous deoxidized copper or oxygen-free copper can be used. The remaining less than 0.01% by mass typically includes silver (Ag) and iron (Fe). In addition, lead (Pb), tin (Sn), antimony (Sb), arsenic (As), bismuth (Bi), chromium (Cr), tellurium (Te), selenium (Se), silicon (Si), etc. are included. .

素材となる高純度銅（Ｃｕ）の純度は高いほど不純物が少なくなるので好ましい。高純度銅（Ｃｕ）の純度は、９９．９９５質量％以上、より好ましくは９９．９９８質量％以上、最も好ましくは９９．９９９８質量％以上である。しかし、本発明の銅合金線においては、ニッケル（Ｎｉ）、白金（Ｐｔ）またはパラジウム（Ｐｄ）の含有量が％オーダーなので、これらのｐｐｍオーダーの不純物の影響は無視することができる。 The higher the purity of the high-purity copper (Cu) that is the material, the less the impurities, the more preferable. The purity of the high purity copper (Cu) is 99.995% by mass or more, more preferably 99.998% by mass or more, and most preferably 99.9998% by mass or more. However, in the copper alloy wire of the present invention, the content of nickel (Ni), platinum (Pt) or palladium (Pd) is on the order of%, so the influence of these ppm-order impurities can be ignored.

本発明の銅合金線は、所定量のイオウ（Ｓ）、あるいは、リン（Ｐ）の存在によって大気中の酸素による酸化の影響を少なくすることができる。よって、不活性雰囲気中であれば最終線径前の線径５０〜２５０μｍで熱処理を施しても、極端に酸素量が増えることがないことがわかった。このような熱処理を施す場合は、非酸化性雰囲気で温度は４００℃〜７００℃で行い、熱処理した線径にて常温での伸び率が５〜２５％となる条件であれば、本発明の酸素量を所定の範囲にとどめることができる。 The copper alloy wire of the present invention can reduce the influence of oxidation by oxygen in the atmosphere due to the presence of a predetermined amount of sulfur (S) or phosphorus (P). Therefore, it was found that the oxygen amount does not increase extremely even if heat treatment is performed at a wire diameter of 50 to 250 μm before the final wire diameter in an inert atmosphere. In the case of performing such heat treatment, the temperature is 400 ° C. to 700 ° C. in a non-oxidizing atmosphere, and the elongation of the wire at the normal temperature is 5 to 25% as long as the elongation rate is 5 to 25%. The amount of oxygen can be kept within a predetermined range.

また、本発明のボールボンディング用銅合金線においては、貴金属めっきされたアルミニウムパッドを用いることができる。ボンディングワイヤからアルミニウムパッド中に酸素が侵入するのを防ぐためである。貴金属めっきは、金（Ａｕ）めっき、銀（Ａｇ）めっき、パラジウム（Ｐｄ）めっきの軟質めっきがよい。また、めっき硬さはボールボンディング用銅合金線の静的硬さと同程度にしておくと、溶融ボールの組成流動をコントロールすることができ、チップ割れを防ぐことができる。具体的にはめっき硬さをヌープ硬さで測定し、ボンディングワイヤのビッカース硬さに近似させることができる。 In the copper alloy wire for ball bonding of the present invention, an aluminum pad plated with noble metal can be used. This is to prevent oxygen from entering the aluminum pad from the bonding wire. The noble metal plating is preferably a soft plating such as gold (Au) plating, silver (Ag) plating, or palladium (Pd) plating. Further, when the plating hardness is set to the same level as the static hardness of the copper alloy wire for ball bonding, the composition flow of the molten ball can be controlled and chip cracking can be prevented. Specifically, the plating hardness can be measured by Knoop hardness and approximated to the Vickers hardness of the bonding wire.

また、本発明においては、リードフレームが銅（Ｃｕ）合金または鉄（Ｆｅ）素材に銅（Ｃｕ）または銅（Ｃｕ）合金が電気めっき等により被覆されたものであるものを用いることもできる。リードフレーム以外にも、ＢＧＡ（Ｂａｌｌ Ｇｒｉｄ Ａｒｒａｙ）のような樹脂基板や、ＱＦＮ（Ｑｕａｄ Ｆｌａｔ Ｎｏｎ−ｌｅａｄｅｄ ｐａｃｋａｇｅ）のようなリードのないフレームなど、ボンディングワイヤが一般的な電気接合線用途として使用される様々なパッケージにも適用されることが可能である。 In the present invention, the lead frame may be a copper (Cu) alloy or an iron (Fe) material coated with copper (Cu) or a copper (Cu) alloy by electroplating or the like. In addition to lead frames, bonding wires such as resin boards such as BGA (Ball Grid Array) and frames without leads such as QFN (Quad Flat Non-Leaded Package) are used for general electrical connection lines. It can also be applied to various packages.

本発明のボールボンディング用銅合金線においては、１週間程度放置しても銅合金線中に含まれる酸素の含有量はほとんど変化しない。しかも、アルミパッドに対して鉛直方向から溶融ボールを押圧してできた圧着ボールの溶着面積が広がらず、花びら状に拡がる現象は生じない。よって、第一ボンディングにおいて安定して均一な溶着面積を確保することができ、高密度実装用ボンディングワイヤとして最適となる。特に直径を１８μｍ以下にしても、溶融ボールが硬くならず、溶着面積がほとんど変化しない。また、生産性、あるいは、セカンド接合性やルーピング特性など他のボンディング特性は、従前のボンディングワイヤと同様に優れている。 In the copper alloy wire for ball bonding of the present invention, the oxygen content contained in the copper alloy wire hardly changes even if it is left for about one week. Moreover, the welded area of the press-bonded ball formed by pressing the molten ball against the aluminum pad from the vertical direction does not widen, and the phenomenon of spreading into a petal shape does not occur. Therefore, a stable and uniform welding area can be secured in the first bonding, which is optimal as a high-density mounting bonding wire. In particular, even when the diameter is 18 μm or less, the molten ball does not become hard and the welding area hardly changes. In addition, productivity and other bonding characteristics such as second bondability and looping characteristics are as excellent as conventional bonding wires.

は、実施例１の溶融ボールの圧着状態を示す顕微鏡写真である。These are the microscope pictures which show the crimping | compression-bonding state of the fusion | melting ball | bowl of Example 1. FIG. は、実施例２の溶融ボールの圧着状態を示す顕微鏡写真である。These are the microscope pictures which show the crimping | compression-bonding state of the fusion | melting ball | bowl of Example 2. FIG. は、実施例３の溶融ボールの圧着状態を示す顕微鏡写真である。These are the microscope pictures which show the crimping | compression-bonding state of the fusion | melting ball | bowl of Example 3. FIG. は、実施例４の溶融ボールの圧着状態を示す顕微鏡写真である。These are the microscope pictures which show the crimping | compression-bonding state of the fusion | melting ball | bowl of Example 4. FIG. は、比較例１の溶融ボールの圧着状態を示す顕微鏡写真である。These are the microscope pictures which show the crimping state of the fusion | melting ball | bowl of the comparative example 1. FIG. は、花びら状の形状の計測手段を示す顕微鏡写真である。These are photomicrographs showing the petal-shaped measuring means. は、従来の偏心ボールの圧着状態を示す顕微鏡写真である。These are the microscope pictures which show the crimping state of the conventional eccentric ball | bowl.

［実施例１］
市販の純度９９．９９９９質量％以上の電解銅素材に、純度９９．９９９質量％以上のニッケル（Ｎｉ）を０．２５質量％、純度９９．９９９質量％以上の白金（Ｐｔ）を０．５質量％、イオウ（Ｓ）を１０質量ｐｐｍ、およびリン（Ｐ）を１５質量ｐｐｍ、それぞれ配合して所定の銅合金線を得た。この合金を連続鋳造後、ダイヤモンドダイスを使用して、連続伸線加工し、直径１８μｍのワイヤを得た。その後、常温での伸び率が１０％となるように、最終連続焼鈍を約５００℃にて行った。このワイヤを室温の大気中に３日間放置した後、この合金ワイヤの酸素濃度を測定したところ、２５質量ｐｐｍであった。このボンディングワイヤを実施例１とした。 [Example 1]
To a commercially available electrolytic copper material having a purity of 99.9999% by mass or more, nickel (Ni) having a purity of 99.999% by mass or more is 0.25% by mass, and platinum (Pt) having a purity of 99.999% by mass or more is 0.5. A predetermined copper alloy wire was obtained by blending 10 mass ppm of sulfur (S) and 15 mass ppm of phosphorus (P). This alloy was continuously cast and then continuously drawn using a diamond die to obtain a wire having a diameter of 18 μm. Thereafter, final continuous annealing was performed at about 500 ° C. so that the elongation at normal temperature was 10%. The wire was left in the air at room temperature for 3 days, and then the oxygen concentration of the alloy wire was measured and found to be 25 ppm by mass. This bonding wire was referred to as Example 1.

（第一ボンドの接合性試験）
この実施例１のボンディングワイヤをボンディングマシン（装置名：キューリックアンドソファー社製ＩＣｏｎｎタイプ）を用いて０．８μｍ厚のＡｌ−０．５質量％Ｃｕパッド上へボールボンディングを１００本連続して行った。このパッドは厚さ０．２０ｍｍのチップ上にある。フリーエアーボール（ＦＡＢ）の作製条件は、ＦＡＢ径が線径の１．５倍となるように設定し、第一ボンドの超音波および荷重の条件は圧着径がＦＡＢの１．３倍となるよう設定した。ループ長さは２．５ｍｍ、ループ高さは３００μｍとした。 (First bond bondability test)
Using the bonding machine of Example 1 (device name: ICon type manufactured by Curik & Sofa Co., Ltd.), 100 ball bondings were continuously made on a 0.8 μm thick Al-0.5 mass% Cu pad. went. This pad is on a 0.20 mm thick chip. The production conditions for the free air ball (FAB) are set so that the FAB diameter is 1.5 times the wire diameter, and the ultrasonic wave and load conditions for the first bond are 1.3 times the crimp diameter. It was set as follows. The loop length was 2.5 mm, and the loop height was 300 μm.

第一ボンドの全数の溶着状態を一般的な測定顕微鏡（オリンパス社製のＳＴＭ６）の対物レンズ５０倍で観察して目視で優と判断した。このボンディングワイヤの圧着ボールの代表的な５個の外観（「実施例１型」と称す）を図１に示す。５個の圧着ボール径の平均値は２７μｍ、圧着ボール厚みは１１μｍであった。 The welding state of all the first bonds was observed with an objective lens 50 times of a general measuring microscope (STM6 manufactured by Olympus) and judged to be excellent visually. FIG. 1 shows five typical appearances (referred to as “Example 1 type”) of the bonding balls of this bonding wire. The average value of the diameters of the five press-bonded balls was 27 μm, and the press-bonded ball thickness was 11 μm.

［実施例２］
市販の純度９９．９９質量％以上の無酸素銅素材に、純度９９．９９質量％以上のニッケル（Ｎｉ）を０．５質量％、純度９９．９９質量％以上のパラジウム（Ｐｄ）を０．２５質量％、イオウ（Ｓ）を１５質量ｐｐｍ、およびリン（Ｐ）を８０質量ｐｐｍ、それぞれ配合して所定の銅合金線を得た。この合金を連続鋳造後、ダイヤモンドダイスを使用して、連続伸線加工した。なお、連続伸線加工途中の直径６０μｍで５００℃の熱処理し、その線径で常温の伸び率を測定すると１５％であった。その後に再度連続伸線加工を行い最終線径１８μｍのワイヤまで加工し、常温での伸び率が１２％となるように、最終連続焼鈍を約５５０℃にて行った。このワイヤを室温の大気中に３日間放置した後、この合金ワイヤの酸素濃度を測定したところ、３１質量ｐｐｍであった。このボンディングワイヤを実施例２とした。 [Example 2]
A commercially available oxygen-free copper material having a purity of 99.99% by mass or more, nickel (Ni) having a purity of 99.99% by mass or more, and 0.5% by mass of palladium (Pd) having a purity of 99.99% by mass or more. 25% by mass, 15% by mass of sulfur (S), and 80% by mass of phosphorus (P) were blended to obtain a predetermined copper alloy wire. This alloy was continuously cast and then continuously drawn using a diamond die. In addition, it heat-processed at 500 degreeC with the diameter of 60 micrometers in the middle of a continuous wire drawing process, and it was 15% when the elongation rate at normal temperature was measured with the wire diameter. Thereafter, continuous wire drawing was performed again to obtain a wire having a final wire diameter of 18 μm, and final continuous annealing was performed at about 550 ° C. so that the elongation at normal temperature was 12%. The wire was left in the air at room temperature for 3 days, and then the oxygen concentration of the alloy wire was measured and found to be 31 ppm by mass. This bonding wire was referred to as Example 2.

（第一ボンドの接合性試験）
この実施例２のボンディングワイヤを実施例１と同様にして１００本ボンディングを行った。第一ボンドの全数の溶着状態を一般的な測定顕微鏡（オリンパス社製ＳＴＭ６）の対物レンズ５０倍で観察して目視で良と判断した。このボンディングワイヤの圧着ボールの代表的な５個の外観（「実施例２型」と称す）を図２に示す。圧着ボール径の平均値は２７μｍ、圧着ボール厚みは１１μｍであった。 (First bond bondability test)
100 bonding wires of Example 2 were bonded in the same manner as in Example 1. The welded state of all the first bonds was observed with an objective lens 50 times of a general measuring microscope (Olympus STM6) and judged to be good visually. FIG. 2 shows five typical appearances (referred to as “Example 2 type”) of the bonding balls of this bonding wire. The average value of the diameter of the press-bonded ball was 27 μm, and the thickness of the press-bonded ball was 11 μm.

［実施例３］
市販の純度９９．９９質量％以上のリン脱酸銅素材に、純度９９．９９質量％以上のニッケル（Ｎｉ）を１．０質量％、純度９９．９９９質量％以上の白金（Ｐｔ）を０．１質量％、純度９９．９９質量％以上のパラジウム（Ｐｄ）を０．０５質量％およびイオウ（Ｓ）を１質量ｐｐｍ、それぞれ配合して所定の銅合金線を得た。この合金を連続鋳造後、ダイヤモンドダイスを使用して、連続伸線加工し、直径１８μｍのワイヤを得た。その後、常温での伸び率が１２％となるように、最終連続焼鈍を約５５０℃にて行った。このワイヤを室温の大気中に３日間放置した後、この合金ワイヤの酸素濃度を測定したところ、３６質量ｐｐｍであった。このボンディングワイヤを実施例３とした。 [Example 3]
Commercially available phosphorous-deoxidized copper material with a purity of 99.99% by mass or more is added with 1.0% by mass of nickel (Ni) with a purity of 99.99% by mass or more and 0 with platinum (Pt) with a purity of 99.999% by mass or more. A predetermined copper alloy wire was obtained by blending 0.05% by mass of palladium (Pd) having a purity of 9% by mass and purity of 99.99% by mass and 1% by mass of sulfur (S). This alloy was continuously cast and then continuously drawn using a diamond die to obtain a wire having a diameter of 18 μm. Thereafter, final continuous annealing was performed at about 550 ° C. so that the elongation at normal temperature was 12%. After this wire was left in the atmosphere at room temperature for 3 days, the oxygen concentration of this alloy wire was measured and found to be 36 mass ppm. This bonding wire was referred to as Example 3.

（第一ボンドの接合性試験）
この実施例３のボンディングワイヤを実施例１と同様にして１００本ボンディングを行った。第一ボンドの全数の溶着状態を一般的な測定顕微鏡（オリンパス社製ＳＴＭ６）の対物レンズ５０倍で観察して目視で可と判断した。このボンディングワイヤの圧着ボールの代表的な５個の外観（「実施例３型」と称す）を図３に示す。圧着ボール径の平均値は２７μｍ、圧着ボール厚みは１１μｍであった。 (First bond bondability test)
100 bonding wires of Example 3 were bonded in the same manner as in Example 1. The welding state of all the first bonds was observed with an objective lens 50 times of a general measurement microscope (Olympus STM6) and judged to be acceptable visually. FIG. 3 shows five typical appearances (referred to as “Example 3 type”) of the bonding balls of this bonding wire. The average value of the diameter of the press-bonded ball was 27 μm, and the thickness of the press-bonded ball was 11 μm.

［実施例４］
市販の純度９９．９９９９質量％以上の電解銅素材に、純度９９．９９質量％以上のニッケル（Ｎｉ）を０．１質量％、純度９９．９９質量％以上の白金（Ｐｔ）を０．１質量％、イオウ（Ｓ）を１０質量ｐｐｍおよびリン（Ｐ）を１０質量ｐｐｍ、それぞれ配合して所定の銅合金線を得た。この合金を溶解鋳造後にて直径５ｍｍの鋳造材を製造した。 [Example 4]
To a commercially available electrolytic copper material having a purity of 99.9999% by mass or more, 0.1% by mass of nickel (Ni) having a purity of 99.99% by mass or more and 0.1% of platinum (Pt) having a purity of 99.99% by mass or more. A predetermined copper alloy wire was obtained by blending 10 mass ppm of sulfur (S) and 10 mass ppm of phosphorus (P). A cast material having a diameter of 5 mm was produced after the alloy was melt cast.

得られた各々の鋳造材について溝ロール、ダイヤモンドダイスを使用して、連続伸線加工した。なお、連続伸線加工途中の直径１００μｍで５００℃の熱処理を行い、その線径で常温の伸び率を測定すると１８％であった。その後に再度連続伸線加工を行い最終線径１８μｍのワイヤまで加工し、常温での伸び率が１３％となるように、最終連続焼鈍を約５５０℃にて行った。このワイヤを室温の大気中に３日間放置した後、この合金ワイヤの酸素濃度を測定したところ、２９質量ｐｐｍであった。このボンディングワイヤを実施例４とした。 Each of the obtained cast materials was continuously drawn using a groove roll and a diamond die. In addition, when heat treatment at 500 ° C. was performed at a diameter of 100 μm in the middle of continuous wire drawing and the elongation at normal temperature was measured with the wire diameter, it was 18%. Thereafter, continuous wire drawing was performed again to obtain a wire having a final wire diameter of 18 μm, and final continuous annealing was performed at about 550 ° C. so that the elongation at normal temperature was 13%. After this wire was left in the air at room temperature for 3 days, the oxygen concentration of the alloy wire was measured and found to be 29 mass ppm. This bonding wire was referred to as Example 4.

（第一ボンドの接合性試験）
この実施例３のボンディングワイヤを実施例１と同様にして１００本ボンディングを行った。第一ボンドの全数の溶着状態を一般的な測定顕微鏡（オリンパス社製ＳＴＭ６）の対物レンズ５０倍で観察して目視で可と判断した。このボンディングワイヤの圧着ボールの代表的な５個の外観（「実施例４型」と称す）を図４に示す。圧着ボール径の平均値は２８μｍ、圧着ボール厚みは１０μｍであった。 (First bond bondability test)
100 bonding wires of Example 3 were bonded in the same manner as in Example 1. The welding state of all the first bonds was observed with an objective lens 50 times of a general measurement microscope (Olympus STM6) and judged to be acceptable visually. FIG. 4 shows typical five appearances (referred to as “Example 4 type”) of the bonding balls of this bonding wire. The average value of the pressure-bonded ball diameter was 28 μm, and the pressure-bonded ball thickness was 10 μm.

［実施例５〜２４］
次に、合金成分の組成を変えて種々のボールボンディング用銅合金線（実施例５〜２４）を作製し、第一ボンドの接合性試験を行った。これらの結果を実施例１〜実施例４の範疇に属するものに分類し、表１に示す。 [Examples 5 to 24]
Next, various alloy compositions for ball bonding (Examples 5 to 24) were produced by changing the composition of the alloy components, and the bondability test of the first bond was performed. These results are classified into those belonging to the categories of Examples 1 to 4 and shown in Table 1.

花びら形状の計測は、基本的に図６の図６−１〜図６−４のようにして行った。圧着ボールの形状は、図６−１のように外周部と内周部とからなる。この圧着ボールの中心軸を通る図６−１の内周部の中心点をMとし、Mを中心として内周部を取り囲むような円を図６−２のように実線で描いた。次に、図６−３のように、圧着ボールの外周部を実線Ｒでなぞった。そして、Ｍを中心にして外周部Ｒまでの半径Ｌを３６０度回転しながら求める。その後、図６−４に示すとおり、Ｌの最大値（Ｌ（Ｍａｘ））をほほ水平方向に表示し、Ｌの最小値（Ｌ（Ｍｉｎ））を右斜め上方に表示した。 The petal shape was basically measured as shown in FIGS. 6-1 to 6-4 in FIG. The shape of the press-bonded ball is composed of an outer peripheral portion and an inner peripheral portion as shown in FIG. The center point of the inner peripheral portion of FIG. 6A that passes through the central axis of this press-bonded ball is M, and a circle surrounding the inner peripheral portion with M as the center is drawn by a solid line as shown in FIG. Next, as shown in FIG. 6-3, the outer periphery of the press-bonded ball was traced with a solid line R. Then, the radius L from the center M to the outer periphery R is obtained while rotating 360 degrees. Thereafter, as shown in FIG. 6-4, the maximum value of L (L (Max)) was displayed in a substantially horizontal direction, and the minimum value of L (L (Min)) was displayed diagonally upward to the right.

花びら形状は、経験的にＬ（Ｍｉｎ）とＬ（Ｍａｘ）の比率が３倍を超えた圧着形状とした。実施例および比較例では、１００個の圧着径の中から発生数の個数を計測した。また、比較例の中にはごく少量であるが、図７に示すような偏心した圧着ボールも含まれた。そこで、花びら形状の比較を容易にするため、Ｌ（Ｍｉｎ）が０となっている角度が３０度以上のものや、Ｌ（Ｍｉｎ）とＬ（Ｍａｘ）の比率が３倍を超えた状態が角度３０度以上連続しているものは、実施例および比較例の花びら形状のカウント数から除外した。実施例および比較例では、花びら形状の発生数が０個のものを◎、発生数が１〜３のものを○、そして、発生数が４個以上のものを×とした。これらの結果を表１右欄に示す。 The petal shape was empirically a crimped shape in which the ratio of L (Min) and L (Max) exceeded 3 times. In the examples and comparative examples, the number of occurrences was measured from 100 crimp diameters. In addition, the comparative example included an eccentric pressure-bonded ball as shown in FIG. Therefore, in order to facilitate the comparison of petal shapes, the angle at which L (Min) is 0 is 30 degrees or more, or the ratio of L (Min) and L (Max) exceeds 3 times. Those having an angle of 30 degrees or more were excluded from the petal-shaped counts of the examples and comparative examples. In Examples and Comparative Examples, the case where the number of occurrences of the petal shape was 0 was evaluated as ◎, the case where the generation number was 1 to 3, and the case where the generation number was 4 or more. These results are shown in the right column of Table 1.

０．８μｍ厚のアルミニウム（Ａｌ−０．５％Ｃｕ）電極膜のダメージは、ボールボンディング直後に割れが発生していないかを、１００個の電極膜で確認した。ボールボンディングされた状態でアルミニウム（Ａｌ）電極膜を上部から観察し、圧着されたボール周辺の電極膜に割れや盛り上がりのダメージが入っている個数を数え、０〜５個を○、６〜１０個を△、１１個以上を×とした。これらの結果を表１右欄に示す。 The damage of the 0.8 μm-thick aluminum (Al-0.5% Cu) electrode film was confirmed with 100 electrode films to determine whether cracks occurred immediately after ball bonding. The aluminum (Al) electrode film is observed from the upper side in a ball-bonded state, and the number of cracks and bulging damages on the electrode film around the pressure-bonded ball is counted. The number was Δ and the number of 11 or more was ×. These results are shown in the right column of Table 1.

Figure 2018064050
Figure 2018064050

［比較例１］
市販の純度９９．９９９９質量％以上の電解銅素材に、純度９９．９９９質量％以上のニッケル（Ｎｉ）を０．０５質量％、純度９９．９９９質量％以上の白金（Ｐｔ）を０．０５質量％およびリン（Ｐ）を１２０質量ｐｐｍ配合して所定の銅合金線を得た。この合金を連続鋳造後、ダイヤモンドダイスを使用して、連続伸線加工し、直径１８μｍのワイヤを得た。その後、常温での伸び率が１１％となるように、最終連続焼鈍を約５００℃にて行った。 [Comparative Example 1]
To a commercially available electrolytic copper material with a purity of 99.9999% by mass or more, 0.05% by mass of nickel (Ni) with a purity of 99.999% by mass or more and 0.05% of platinum (Pt) with a purity of 99.999% by mass or more. A predetermined copper alloy wire was obtained by blending 120 mass ppm of mass% and phosphorus (P). This alloy was continuously cast and then continuously drawn using a diamond die to obtain a wire having a diameter of 18 μm. Thereafter, final continuous annealing was performed at about 500 ° C. so that the elongation at normal temperature was 11%.

このワイヤを室温の大気中に３日間放置した後、この合金ワイヤの酸素濃度を測定したところ、３０質量ｐｐｍであった。このボンディングワイヤを比較例１とした。この比較例１はニッケル（Ｎｉ）と白金（Ｐｔ）の含有量が下限値を下回り、リン（Ｐ）の含有量が上限値を超えている。 After this wire was left in the atmosphere at room temperature for 3 days, the oxygen concentration of this alloy wire was measured and found to be 30 ppm by mass. This bonding wire was referred to as Comparative Example 1. In Comparative Example 1, the contents of nickel (Ni) and platinum (Pt) are below the lower limit, and the content of phosphorus (P) exceeds the upper limit.

（第一ボンドの接合性試験）
この比較例１のボンディングワイヤを実施例１と同様にして１００本ボンディングを行った。第一ボンドの全数の溶着状態を一般的な測定顕微鏡（オリンパス社製ＳＴＭ６）の対物レンズ５０倍で観察して目視で不可と判断した。このボンディングワイヤの圧着ボールの代表的な５個の外観（「比較例型」と称す）を図５に示す。 (First bond bondability test)
100 bonding wires of Comparative Example 1 were bonded in the same manner as in Example 1. The welding state of the total number of the first bonds was observed with an objective lens 50 times of a general measuring microscope (Olympus STM6), and visually judged as impossible. FIG. 5 shows five typical appearances (referred to as “comparative example molds”) of the bonding balls of this bonding wire.

［比較例２〜５］
同様にして比較例２〜４のボールボンディング用銅合金線を作製し、第一ボンドの接合性試験を行った。これらの組成と結果を表１に示す。比較例２は、白金（Ｐｔ）の含有量が上限値を超えている。また、リン（Ｐ）の含有量が下限値を下回っている。比較例３は、酸素（Ｏ）の含有量が上限値を超え、かつ、イオウ（Ｓ）の含有量が下限値を下回っている。比較例４は、パラジウム（Ｐｄ）の含有量が下限値を下回り、かつ、イオウ（Ｓ）の含有量が上限値を超えている。 [Comparative Examples 2 to 5]
Similarly, copper alloy wires for ball bonding of Comparative Examples 2 to 4 were produced, and the bondability test of the first bond was performed. These compositions and results are shown in Table 1. In Comparative Example 2, the platinum (Pt) content exceeds the upper limit. Moreover, phosphorus (P) content is less than a lower limit. In Comparative Example 3, the oxygen (O) content exceeds the upper limit value, and the sulfur (S) content is lower than the lower limit value. In Comparative Example 4, the content of palladium (Pd) is below the lower limit, and the content of sulfur (S) exceeds the upper limit.

図１〜図５および表１の結果から明らかなように、本発明の実施例１〜２４のボールボンディング用銅合金線においては、銅合金線を細くして溶融ボールを小さくしても、圧着ボール形状が安定し、圧着ボールが花びら状に拡がらないことがわかる。図１〜図５で示すように、圧着ボール形状が良かった順序は、実施例１型≒実施例２型≒実施例３型＞実施例４型＞比較例１型の順序であった。図１〜図５では判読しにくいが、特に実施例１および実施例２の銅合金線がボンディングワイヤとして優れていることがわかる。このことは図１〜図５に例示されているとおりである。 As is apparent from the results of FIGS. 1 to 5 and Table 1, in the copper alloy wires for ball bonding of Examples 1 to 24 of the present invention, even if the copper alloy wire is thinned and the molten ball is made small, it is crimped. It can be seen that the ball shape is stable, and the press-bonded ball does not expand into a petal shape. As shown in FIGS. 1 to 5, the order in which the press-bonded ball shape was good was the order of Example 1 type≈Example 2 type≈Example 3 type> Example 4 type> Comparative Example 1 type. Although it is hard to read in FIGS. 1-5, it turns out that especially the copper alloy wire of Example 1 and Example 2 is excellent as a bonding wire. This is as illustrated in FIGS.

他方、表１の結果から明らかなように、比較例１〜４のボールボンディング用銅合金線は、圧着ボール形状が安定せず、圧着ボールが花びら状に拡がっていることがわかる。このことは、図５にも例示されているように、圧着ボール形状が花びら状に観察されることからも理解できる。また、比較例２はアルミニウム電極膜のダメージ発生数が実施例よりも著しく多いことがわかる。 On the other hand, as can be seen from the results in Table 1, it can be seen that in the copper alloy wires for ball bonding of Comparative Examples 1 to 4, the shape of the press-bonded ball is not stable, and the press-bonded ball spreads into a petal shape. This can also be understood from the fact that the press-bonded ball shape is observed in the shape of a petal as illustrated in FIG. Moreover, it turns out that the comparative example 2 has remarkably much damage generation | occurrence | production number of an aluminum electrode film rather than an Example.

本発明ボールボンディング用銅合金線は、携帯電話といった携帯用電子機器、自動車などに載置される電子部品、医療機器、産業用ロボットなどの各種の電気・電子機器に組み込まれる半導体装置のボンディングワイヤのみならず、これらの電気・電子機器の電線、代表的には同軸ケーブルの極細線に好適に利用することができる。

The copper alloy wire for ball bonding of the present invention is a bonding wire for a semiconductor device incorporated in various electric / electronic devices such as portable electronic devices such as mobile phones, electronic parts mounted on automobiles, medical devices, industrial robots, etc. It can be suitably used not only for the electric wires of these electric / electronic devices, but typically for the ultrafine wires of coaxial cables.

Figure 2018064050
Figure 2018064050

Claims (6)

ボールボンディング用ワイヤにおいて、０．１〜１．５質量％のニッケル（Ｎｉ）、白金（Ｐｔ）またはパラジウム（Ｐｄ）のうちのいずれか１種以上を合計で０．０１〜１．５質量％、更に０．１〜２０質量ｐｐｍのイオウ（Ｓ）、１０〜８０質量ｐｐｍの酸素（Ｏ）および残部銅（Ｃｕ）からなることを特徴とするボールボンディング用銅合金線。 In the ball bonding wire, a total of 0.01 to 1.5% by mass of any one or more of 0.1 to 1.5% by mass of nickel (Ni), platinum (Pt) or palladium (Pd) A copper alloy wire for ball bonding, further comprising 0.1 to 20 ppm by mass of sulfur (S), 10 to 80 ppm by mass of oxygen (O), and the balance copper (Cu). ボールボンディング用ワイヤにおいて、０．１〜１．５質量％のニッケル（Ｎｉ）、白金（Ｐｔ）またはパラジウム（Ｐｄ）のうちのいずれか１種以上を合計で０．０１〜１．５質量％、更に１０〜１００質量ｐｐｍのリン（Ｐ）、１０〜８０質量ｐｐｍの酸素（Ｏ）および残部銅（Ｃｕ）からなることを特徴とするボールボンディング用銅合金線。 In the ball bonding wire, a total of 0.01 to 1.5% by mass of any one or more of 0.1 to 1.5% by mass of nickel (Ni), platinum (Pt) or palladium (Pd) A copper alloy wire for ball bonding, further comprising 10 to 100 ppm by mass of phosphorus (P), 10 to 80 ppm by mass of oxygen (O), and the balance copper (Cu). ボールボンディング用ワイヤにおいて、０．１〜１．５質量％のニッケル（Ｎｉ）、白金（Ｐｔ）またはパラジウム（Ｐｄ）のうちのいずれか１種以上を合計で０．０１〜１．５質量％、更に０．１〜２０質量ｐｐｍのイオウ（Ｓ）、１０〜１００質量ｐｐｍのリン（Ｐ）、１０〜８０質量ｐｐｍの酸素（Ｏ）および残部銅（Ｃｕ）からなることを特徴とするボールボンディング用銅合金線 In the ball bonding wire, a total of 0.01 to 1.5% by mass of any one or more of 0.1 to 1.5% by mass of nickel (Ni), platinum (Pt) or palladium (Pd) Further, a ball comprising 0.1 to 20 mass ppm of sulfur (S), 10 to 100 mass ppm of phosphorus (P), 10 to 80 mass ppm of oxygen (O) and the balance copper (Cu). Copper alloy wire for bonding 上記ニッケル（Ｎｉ）の含有量が０．２〜１．２質量％であることを特徴とする請求項１〜請求項３のいずれかに記載のボールボンディング用銅合金線。 The copper alloy wire for ball bonding according to any one of claims 1 to 3, wherein a content of the nickel (Ni) is 0.2 to 1.2 mass%. 上記白金（Ｐｔ）またはパラジウム（Ｐｄ）の含有量が０．０５〜０．８質量％であることを特徴とする請求項１〜請求項３のいずれかに記載のボールボンディング用銅合金線 4. The copper alloy wire for ball bonding according to claim 1, wherein the platinum (Pt) or palladium (Pd) content is 0.05 to 0.8 mass%. 上記イオウ（Ｓ）の含有量が２〜１０質量ｐｐｍであることを特徴とする請求項１または請求項３のいずれかに記載のボールボンディング用銅合金線。
4. The copper alloy wire for ball bonding according to claim 1, wherein the sulfur (S) content is 2 to 10 ppm by mass.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108929968A (en) * 2018-07-18 2018-12-04 合肥择浚电气设备有限公司 A kind of production technology of high conductivity copper alloy wire
CN108962859A (en) * 2018-07-17 2018-12-07 四川威纳尔特种电子材料有限公司 A kind of silver-base alloy bonding wire of plating nickel on surface and preparation method thereof
CN109449087A (en) * 2018-10-24 2019-03-08 深圳粤通应用材料有限公司 A kind of copper plating palladium nickel plating bonding wire and preparation method thereof again
CN113646450A (en) * 2019-02-08 2021-11-12 田中电子工业株式会社 Palladium-covered copper bonding wire, wire bonding structure, semiconductor device, and method for manufacturing semiconductor device

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020218968A1 (en) * 2019-04-26 2020-10-29 Heraeus Materials Singapore Pte. Ltd. Coated wire
CN111774752B (en) * 2020-07-15 2021-10-29 荆州市弘晟光电科技有限公司 Copper wire welding process

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6120693A (en) * 1984-07-06 1986-01-29 Toshiba Corp Bonding wire
JP2014070252A (en) * 2012-09-28 2014-04-21 Tanaka Electronics Ind Co Ltd Copper platinum alloy fine wire for connecting semiconductor device
JP2014075458A (en) * 2012-10-03 2014-04-24 Tanaka Electronics Ind Co Ltd Copper rhodium alloy thin wire for connection of semiconductor device

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01291435A (en) 1988-05-18 1989-11-24 Mitsubishi Metal Corp Extrafine copper alloy wire for semiconductor device and semiconductor device
JPH01290231A (en) 1988-05-18 1989-11-22 Mitsubishi Metal Corp Semiconductor device and copper allow extremely fine wire therefor
WO2003076672A1 (en) * 2002-03-12 2003-09-18 The Furukawa Electric Co., Ltd. High-strength high-conductivity copper alloy wire rod of excellent resistance to stress relaxation characteristics
JP4691533B2 (en) * 2006-08-31 2011-06-01 新日鉄マテリアルズ株式会社 Copper alloy bonding wire for semiconductor devices
JP4482605B1 (en) * 2009-01-23 2010-06-16 田中電子工業株式会社 High purity Cu bonding wire
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
SG190481A1 (en) * 2011-12-01 2013-06-28 Heraeus Materials Tech Gmbh Alloyed 2n copper wire for bonding in microelectronics device
JP5668087B2 (en) 2013-02-22 2015-02-12 田中電子工業株式会社 Structure of copper dilute nickel alloy wire for semiconductor device bonding

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6120693A (en) * 1984-07-06 1986-01-29 Toshiba Corp Bonding wire
JP2014070252A (en) * 2012-09-28 2014-04-21 Tanaka Electronics Ind Co Ltd Copper platinum alloy fine wire for connecting semiconductor device
JP2014075458A (en) * 2012-10-03 2014-04-24 Tanaka Electronics Ind Co Ltd Copper rhodium alloy thin wire for connection of semiconductor device

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108962859A (en) * 2018-07-17 2018-12-07 四川威纳尔特种电子材料有限公司 A kind of silver-base alloy bonding wire of plating nickel on surface and preparation method thereof
CN108929968A (en) * 2018-07-18 2018-12-04 合肥择浚电气设备有限公司 A kind of production technology of high conductivity copper alloy wire
CN109449087A (en) * 2018-10-24 2019-03-08 深圳粤通应用材料有限公司 A kind of copper plating palladium nickel plating bonding wire and preparation method thereof again
CN113646450A (en) * 2019-02-08 2021-11-12 田中电子工业株式会社 Palladium-covered copper bonding wire, wire bonding structure, semiconductor device, and method for manufacturing semiconductor device
US11876066B2 (en) 2019-02-08 2024-01-16 Tanaka Denshi Kogyo K.K. Palladium-coated copper bonding wire, wire bonding structure, semiconductor device, and manufacturing method of semiconductor device

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