JP3736033B2

JP3736033B2 - Method for producing copper alloy material for electronic equipment

Info

Publication number: JP3736033B2
Application number: JP13198797A
Authority: JP
Inventors: 佳紀山本; 元佐々木
Original assignee: Hitachi Cable Ltd
Current assignee: Hitachi Cable Ltd
Priority date: 1997-05-22
Filing date: 1997-05-22
Publication date: 2006-01-18
Anticipated expiration: 2017-05-22
Also published as: JPH10317116A

Description

【０００１】
【発明の属する技術分野】
本発明は半導体装置用リードフレーム材等に用いられる電子機器用銅合金材の製造方法に関し、特に、エッチングによる微細加工性、機械的強度、及び電気・熱伝導性の向上を図れるようにした電子機器用銅合金材の製造方法に関する。
【０００２】
【従来の技術】
電子機器用銅合金材である半導体装置用リードフレーム材は、搭載される半導体素子の高集積化の傾向から半導体素子で発生するジュール熱を効率良く発散させるために熱伝導性、つまり、導電率が高くなっていることが要求されている。また、半導体素子の高集積化に伴う多ピン化、及びピン幅、ピンピッチの縮小化によってリードフレームの薄板化が進められているため、同時に高い機械的強度を備えていることも要求されている。
【０００３】
このような要求がある中、従来は半導体装置用リードフレーム材に、例えば、Ｃｕ（銅）−Ｎｉ−Ｐ系の銅合金材を使用している。この銅合金材は、析出硬化性を示し、適当な条件で溶体化処理、及び時効処理を行ってＮｉとＰの化合物を微細に析出させると、高い機械的強度と良好な熱伝導性が得られることから、上記要求のある半導体装置用リードフレーム材として好適である。
【０００４】
ところで、半導体装置用リードフレームを製造する場合、スタンピング、或いはエッチングによる外形加工が実施されているが、特に、２００ピンを越えるような高密多ピンリードフレームの外形加工には、微細加工が容易なエッチング法が採用されている。こうした高密度多ピンリードフレームでは、インナーリードの幅がボンディングに必要な幅に対して限界値に近く、ピンピッチも非常に狭くなるため、エッチング時にリードの直線性や寸法精度を正確にコントロールすることが重要になる。リードの外形加工精度は、エッチングの処理条件以外にも材料そのものの特性が大きく関係している。
【０００５】
【発明が解決しようとする課題】
しかし、従来の電子機器用銅合金材の製造方法によると、溶体化処理、及び時効処理を行っているため、結晶粒径や析出物が粗大化する恐れがあり、この場合にはエッチングによる微細加工性を低下させるという問題がある。即ち、結晶粒径が大きく粒界密度が低い銅合金材では、粒界部と粒内部のエッチングによる加工特性が異なるため、エッチング面に凹凸が生じ易い。また、析出物が粗大化した銅合金材でも同様となる。結晶粒が粗大化する恐れのある工程として、溶体化処理をあげることができる。適切な時効処理によって高い強度を得るためには、その前処理として高温での溶体化処理により析出元素を十分固溶させておく必要があり、この高温による熱処理の際に結晶粒の粗大化が生じ易い。一方、溶体化処理の熱処理の温度を低下させると、析出物の粗大化が生じ易く、強度、及び熱伝導性を良好にできないばかりでなく、エッチングによる微細加工性に影響を及ぼすことになる。
【０００６】
従って、本発明の目的はエッチングによる微細加工性、機械的強度、及び電気・熱伝導性の向上を図れるようにした電子機器用銅合金材の製造方法を提供することである。
【０００７】
【課題を解決するための手段】
本発明は上記問題点に鑑み、エッチングによる微細加工性、機械的強度、及び電気・熱伝導性の向上を図れるようにするため、ＮｉとＰを含有する銅合金材を鋳造し、銅合金材に所定の温度の溶体化処理を施し、溶体化処理を施された銅合金材に第１の所定の加工率の第１の冷間加工を施し、第１の冷間加工を施された銅合金材に第１の所定の温度と第１の所定の時間の第１の時効処理を施し、第１の時効処理を施された銅合金材に第１の所定の加工率より小さい第２の所定の加工率の第２の冷間加工を施し、第２の冷間加工を施された銅合金材に第２の所定の温度と第２の所定の時間の第２の時効処理を施すようにした電子機器用銅合金材の製造方法を提供するものである。
【０００８】
上記溶体化処理は、上記所定の温度を７５０〜９００℃に設定して行い、上記第１の冷間加工は、上記第１の所定の加工率を６０％以上の値に設定して行い、上記第１の時効処理は、上記第１の所定の温度を４００〜５００℃に、上記第１の所定の時間を３０分〜３時間にそれぞれ設定して行い、上記第２の冷間加工は、上記第２の所定の加工率を５０％以下の値に設定して行い、上記第２の時効処理は、上記第２の所定の温度を３５０〜５００℃に、上記第２の所定の時間を３０分〜３時間にそれぞれ設定して行うことが好ましい。
【０００９】
また、上記鋳造は、１．０〜４．０ｍａｓｓ％のＮｉと０．２〜０．８ｍａｓｓ％のＰを質量比４〜６の範囲で含み、且つ、副成分として０．１〜５．０ｍａｓｓ％のＺｎを含み、残部Ｃｕからなる銅合金材とすることにより行うことが好ましい。
【００１０】
以上述べた電子機器用銅合金材の製造方法によると、溶体化処理の温度を７５０〜９００℃に設定しているため、結晶粒の粗大化を防止すると共に析出元素を十分に固溶させることができる。溶体化温度が７５０℃より低くなると、析出元素の固溶が十分に進まない。よって、後工程の時効処理で固溶し残った析出物の粗大化が生じ、高強度が得られないと共にエッチングによる微細加工性も低下する。一方、溶体化温度が９００℃より高くなると、析出元素の固溶は進むが、結晶粒の粗大化が生じる。よって、最終材で微細な結晶粒が得られ難くなり、エッチングによる微細加工性が低下する。なお、上記範囲の中で８００〜８５０℃に設定すると、上記した効果が顕著になる。
【００１１】
また、溶体化処理と第１の時効処理の間に第１の冷間加工を施しているため、加工によって結晶粒を微細化すると共に、析出物形成の起点となる格子欠陥を導入することで第１の時効処理時に微細析出物の形成を促すことができる。前述したように、エッチングによる微細加工性を向上させるためには十分な結晶粒の微細化が必要であり、この冷間加工の加工率を高めることは結晶粒の微細化に対して大きい効果を有している。また、第１の冷間加工の加工率を６０％以上に設定しているため、上記の効果を十分に得ることができる。
【００１２】
また、第１の時効処理では、加工率の高い材料を時効するため、析出が進行し易く、粗大析出物が発生し易く、また、処理温度が高くなると、再結晶が進行して結晶粒径が大きくなるが、本発明では処理温度を４００〜５００℃、処理時間を３０分〜３時間に設定しているため、粗大析出物の発生を抑え、結晶粒径を微細に保ちながら析出を進行させることができる。なお、上記範囲の中で処理温度を４４０〜４８０℃に、処理時間を１〜２時間に設定すると、上記した効果が顕著になる。
【００１３】
また、第１の時効処理と第２の時効処理の間に第２の冷間加工を施しているため、析出物形成の起点となる格子欠陥を導入することで第２の時効処理時に新たな微細析出物の形成を促すことができる。即ち、第１の時効処理のみでは析出しきれずに固溶状態で残留する合金元素があり、このままでは良好な導電性の達成が不十分となるが、本発明ではこのような不具合を解決することができる。第２の冷間加工の加工率を高くした場合、第２の時効処理時に粗大析出物が発生し易くなると共に、第２の時効処理後の残留歪みが大きくなり、半導体装置用リードフレームの製造ではリード成形のときにリードの反りが発生する。本発明では第２の冷間加工の加工率を５０％以下にしているため、こうした問題を抑えることができる。
【００１４】
また、第２の時効処理において処理温度を３５０〜５００℃に、保持時間を３０分〜３時間に設定しているため、粗大析出物の発生を抑え、結晶粒径を微細に保ちながら新たな析出物を発生させ、固溶元素量を減らすことができる。即ち、処理条件が低温短時間になると、析出を十分に進行させることができない。また、残留歪みが残るため、半導体装置用リードフレームの製造では、リード成形のときにリードの反りが発生する。一方、処理条件が高温長時間になると、粗大析出物が発生すると共に再結晶が進行して結晶粒径が大きくなる。なお、上記範囲の中で処理温度を４００〜４８０℃に、処理時間を１〜２時間に設定すると、上記した効果が顕著になる。
【００１５】
更に、銅合金材においてＮｉの添加量を１．０〜４．０ｍａｓｓ％に、Ｐの添加量を０．２〜０．８ｍａｓｓ％に設定しているため、析出による高強度化が十分得られると共に、時効処理後の固溶元素量を減少させることができる。即ち、ＮｉとＰの添加量が上記範囲の下限値より低くなると、析出による高強度化が十分に起こらない。また、ＮｉとＰの添加量が上記範囲の上限値より高くなると、析出しきれない固溶元素量が増加する。また、Ｎｉ／Ｐの質量比が４〜６に設定されているため、ＮｉとＰがＮｉ_５Ｐ_２を形成して析出したときに余剰分として存在するＮｉ、或いはＰの量を少なくすることができる。また、Ｚｎを０．１〜５．０ｍａｓｓ％添加すると、はんだ付けのときの界面剥離を防ぐことができる。このとき、添加量が０．１ｍａｓｓ％より少ないと、十分な効果が得られず、また、添加量が５．０ｍａｓｓ％より多いと、導電性を低下させてしまう。なお、上記範囲の中で、Ｎｉの添加量を１．５〜２．５ｍａｓｓ％に、Ｐの添加量を０．３〜０．５ｍａｓｓ％に、Ｚｎの添加量を０．１〜２．０ｍａｓｓ％に設定すると、上記した効果が顕著になる。
【００１６】
【実施例】
以下、本発明の電子機器用銅合金材の製造方法を詳細に説明する。
【００１７】
表１に示す組成を有する組成記号Ａ〜Ｄの銅合金に対し、表２に示す製造条件に基づいて実施例と比較例の試料１〜１５を製造した。
【００１８】
【表１】

【表２】

【００１９】
ここで、試料１の製造手順を説明する。まず、無酸素銅を母材にして表１に示す組成記号Ａの組成を有する銅合金を高周波溶解炉で溶製し、直径３０ｍｍ，長さ２５０ｍｍのインゴットを鋳造した。次に、これを８５０℃に加熱して押出加工し、幅２０ｍｍ，厚さ８ｍｍの板状にした後、厚さ０．７ｍｍまで冷間圧延した。続いて、冷間圧延した銅合金を８００℃に加熱して１０分間保持した後、水中に投入して急冷し、溶体化した。そして、これを加工率７０％で冷間圧延して厚さ０．２１ｍｍにし、その後、これに４７０℃で１時間保持する第１次時効処理を施した。更に、第１次時効処理を施した銅合金を加工率３０％で冷間圧延して厚さ０．１５ｍｍにし、その後、これに４００℃で１時間保持する第２次時効処理を施して実施例である試料１を得た。
【００２０】
また、実施例である試料２，３及び比較例である試料４〜１１は、表１に示す記号組成Ａの組成を有する銅合金に対して、溶体化処理の温度，溶体化処理後の冷間圧延の加工率，第１次時効処理の温度，第１次時効処理後の冷間圧延の加工率，及び第２次時効処理の温度をそれぞれ表２に示すように変えて試料１と同様に製造した。
【００２１】
更に、実施例である試料１２は、表１に示す記号組成Ｂの組成を有する銅合金に対して、試料１と同一な条件で各処理を施して製造した。
【００２２】
更にまた、比較例である試料１３〜１５は、表１に示す記号組成Ｃ，Ｄ，Ｅの組成を有する銅合金に対して、試料１と同一な条件で各処理を施して製造した。
【００２３】
次に、このようにして得た試料１〜１５について引張強さ，導電率，結晶粒径を測定した。表３はその測定結果を示す。
【表３】

表３から明らかなように、実施例である試料１〜３及び試料１２は、強度、及び導電率が良好であると共に、結晶粒径の微細化、つまり、エッチングによる微細加工性の向上が達成されている。
【００２４】
一方、試料４，５は溶体化処理の温度が本発明の範囲を外れた比較例であり、処理温度が高い試料４では結晶粒が大きくなり、処理温度が低い試料５では良好な強度、及び導電率が得られていない。試料６は溶体処理後の冷間圧延の加工率が本発明の範囲より低い比較例であり、結晶粒の微細化が不十分である。試料７，８は第１次時効処理の温度が本発明の範囲を外れた比較例であり、何れも強度が不十分である。試料９は第１次時効処理後の冷間圧延の加工率が本発明の範囲より高い比較例であり、強度が不十分である。試料１０，１１は第２次時効処理の温度が本発明の範囲を外れた比較例であり、処理温度が低い試料１０では導電率が不十分であり、処理温度が高い試料１１では強度、及び結晶粒の微細化が不十分である。試料１３〜１５は合金組成が本発明の範囲を外れた比較例であり、何れも強度、及び導電率が不十分である。
【００２５】
以上述べた実施例による電子機器用銅合金材は、機械的強度、電気・熱伝導性、及びエッチングによる微細加工性が優れているため、より小形・多ピンの半導体装置用リードフレームとして好適な材料とすることができる。
【００２６】
【発明の効果】
以上説明したように、本発明の電子機器用銅合金材の製造方法によると、ＮｉとＰを含む銅合金を溶体化処理した後、冷間加工と時効処理をそれぞれ２回繰り返し行い、且つ、溶体化処理の温度、冷間加工の加工率、及び時効処理の温度を所定の値に設定したため、エッチングによる微細加工性、機械的強度、及び電気・熱伝導性の向上を図ることができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a copper alloy material for electronic equipment used for a lead frame material for a semiconductor device, and in particular, an electron capable of improving fine workability, mechanical strength, and electrical / thermal conductivity by etching. The present invention relates to a method for manufacturing a copper alloy material for equipment.
[0002]
[Prior art]
Lead frame materials for semiconductor devices, which are copper alloy materials for electronic equipment, have thermal conductivity, that is, conductivity, in order to efficiently dissipate Joule heat generated in semiconductor elements due to the trend toward higher integration of semiconductor elements. Is required to be high. In addition, since the lead frame is made thinner by increasing the number of pins accompanying the high integration of semiconductor elements and reducing the pin width and pin pitch, it is also required to have high mechanical strength at the same time. .
[0003]
Under such demand, conventionally, for example, a Cu (copper) -Ni-P-based copper alloy material is used as a lead frame material for a semiconductor device. This copper alloy material exhibits precipitation hardenability, and when subjected to solution treatment and aging treatment under appropriate conditions to precipitate Ni and P compounds finely, high mechanical strength and good thermal conductivity are obtained. Therefore, it is suitable as a lead frame material for a semiconductor device having the above requirements.
[0004]
By the way, when manufacturing a lead frame for a semiconductor device, the outer shape is processed by stamping or etching, but fine processing is particularly easy for the outer shape processing of a high-density multi-pin lead frame exceeding 200 pins. Etching method is adopted. In such a high-density, multi-pin lead frame, the inner lead width is close to the limit required for bonding and the pin pitch is very narrow, so that the linearity and dimensional accuracy of the lead can be accurately controlled during etching. Becomes important. In addition to the etching processing conditions, the characteristics of the material itself are greatly related to the lead external processing accuracy.
[0005]
[Problems to be solved by the invention]
However, according to the conventional method for producing a copper alloy material for electronic equipment, since the solution treatment and the aging treatment are performed, the crystal grain size and the precipitate may be coarsened. There is a problem that workability is lowered. That is, in a copper alloy material having a large crystal grain size and a low grain boundary density, the processing characteristics of the grain boundary part and the inside of the grain are different, so that the etched surface is likely to be uneven. The same applies to a copper alloy material with coarse precipitates. A solution treatment can be given as a process in which the crystal grains may be coarsened. In order to obtain high strength by appropriate aging treatment, it is necessary to sufficiently dissolve the precipitated elements by solution treatment at a high temperature as a pretreatment, and the crystal grains are coarsened during the heat treatment at this high temperature. It is likely to occur. On the other hand, when the temperature of the heat treatment for solution treatment is lowered, the precipitates are likely to be coarsened, and not only the strength and thermal conductivity cannot be improved, but also the fine workability by etching is affected.
[0006]
Accordingly, an object of the present invention is to provide a method for producing a copper alloy material for electronic equipment which can improve the fine workability, mechanical strength, and electrical / thermal conductivity by etching.
[0007]
[Means for Solving the Problems]
In view of the above-mentioned problems, the present invention casts a copper alloy material containing Ni and P in order to improve the fine workability by etching, mechanical strength, and electrical / thermal conductivity. The solution is subjected to a solution treatment at a predetermined temperature, and the copper alloy material subjected to the solution treatment is subjected to a first cold working at a first predetermined working rate, and the copper subjected to the first cold working The alloy material is subjected to a first aging treatment at a first predetermined temperature and a first predetermined time, and the second aging treatment is applied to the copper alloy material subjected to the first aging treatment, which is smaller than the first predetermined processing rate. The second cold working at a predetermined working rate is performed, and the second aging treatment at the second predetermined temperature and the second predetermined time is performed on the copper alloy material subjected to the second cold working. The manufacturing method of the copper alloy material for electronic devices made in this way is provided.
[0008]
The solution treatment is performed by setting the predetermined temperature to 750 to 900 ° C., and the first cold processing is performed by setting the first predetermined processing rate to a value of 60% or more, The first aging treatment is performed by setting the first predetermined temperature to 400 to 500 ° C. and the first predetermined time to 30 minutes to 3 hours, and the second cold working is performed The second predetermined processing rate is set to a value of 50% or less, and the second aging treatment is performed by setting the second predetermined temperature to 350 to 500 ° C. and the second predetermined time. Is preferably set to 30 minutes to 3 hours.
[0009]
Moreover, the casting includes 1.0～4.0Mass% of Ni and 0.2～0.8Mass% of P in the range of mass ratios 4-6 and 0.1-5 as an auxiliary component. look including the 0Mass% of Zn, it is preferably performed by a copper alloy material and the balance Cu.
[0010]
According to the method for producing a copper alloy material for electronic equipment described above, since the temperature of the solution treatment is set to 750 to 900 ° C., the coarsening of crystal grains is prevented and the precipitated elements are sufficiently dissolved. Can do. When the solution temperature is lower than 750 ° C., the solid solution of the precipitated elements does not proceed sufficiently. Accordingly, the precipitates that remain in the solid solution in the subsequent aging treatment are coarsened, so that high strength cannot be obtained and the fine workability by etching also decreases. On the other hand, when the solution temperature is higher than 900 ° C., the solid solution of the precipitated elements proceeds, but the crystal grains become coarse. Therefore, it becomes difficult to obtain fine crystal grains in the final material, and fine workability by etching is lowered. In addition, when it sets to 800-850 degreeC in the said range, the above-mentioned effect will become remarkable.
[0011]
In addition, since the first cold working is performed between the solution treatment and the first aging treatment, the crystal grains are refined by the processing, and lattice defects that are the starting points of the precipitate formation are introduced. Formation of fine precipitates can be promoted during the first aging treatment. As described above, in order to improve the fine workability by etching, it is necessary to refine the crystal grains sufficiently. Increasing the processing rate of this cold work has a great effect on the refinement of the crystal grains. Have. Moreover, since the processing rate of the 1st cold processing is set to 60% or more, said effect can fully be acquired.
[0012]
In the first aging treatment, since a material with a high processing rate is aged, precipitation is likely to proceed, coarse precipitates are likely to be generated, and recrystallization proceeds to increase the crystal grain size when the treatment temperature is high. However, in the present invention, since the processing temperature is set to 400 to 500 ° C. and the processing time is set to 30 minutes to 3 hours, the generation of coarse precipitates is suppressed, and the precipitation proceeds while the crystal grain size is kept fine. Can be made. In addition, when the processing temperature is set to 440 to 480 ° C. and the processing time is set to 1 to 2 hours within the above-mentioned range, the above-described effect becomes remarkable.
[0013]
In addition, since the second cold working is performed between the first aging treatment and the second aging treatment, new lattice processing defects are introduced at the time of the second aging treatment by introducing lattice defects that are the starting points of precipitate formation. Formation of fine precipitates can be promoted. That is, there is an alloy element that cannot be fully precipitated and remains in a solid solution state only by the first aging treatment, and if it remains as it is, it is insufficient to achieve good conductivity, but the present invention solves such a problem. Can do. When the processing rate of the second cold working is increased, coarse precipitates are likely to be generated during the second aging treatment, and the residual strain after the second aging treatment is increased, thereby producing a lead frame for a semiconductor device. Then, warping of the lead occurs during lead molding. In the present invention, since the processing rate of the second cold working is 50% or less, such a problem can be suppressed.
[0014]
In addition, since the treatment temperature is set to 350 to 500 ° C. and the holding time is set to 30 minutes to 3 hours in the second aging treatment, generation of coarse precipitates is suppressed, and a new crystal grain size is maintained while maintaining a fine grain size. Precipitates can be generated and the amount of solid solution elements can be reduced. That is, when the processing conditions are low temperature and short time, the precipitation cannot be sufficiently advanced. In addition, since residual strain remains, lead warpage occurs during lead molding in the manufacture of lead frames for semiconductor devices. On the other hand, when the treatment conditions are high temperature for a long time, coarse precipitates are generated and recrystallization proceeds to increase the crystal grain size. In addition, when the processing temperature is set to 400 to 480 ° C. and the processing time is set to 1 to 2 hours in the above range, the above-described effect becomes remarkable.
[0015]
Further, since the addition amount of Ni is set to 1.0 to 4.0 mass% and the addition amount of P is set to 0.2 to 0.8 mass% in the copper alloy material, sufficiently high strength can be obtained by precipitation. At the same time, the amount of the solid solution element after the aging treatment can be reduced. That is, when the addition amounts of Ni and P are lower than the lower limit of the above range, the strength is not sufficiently increased by precipitation. Moreover, when the addition amount of Ni and P becomes higher than the upper limit of the said range, the amount of solid solution elements which cannot be precipitated will increase. Moreover, since the mass ratio of Ni / P is set to 4-6, reducing Ni, or the amount of P present as excess when Ni and P was deposited to form a Ni ₅ P ₂ be able to. Moreover, when 0.1 to 5.0 mass% of Zn is added, interfacial peeling at the time of soldering can be prevented. At this time, if the addition amount is less than 0.1 mass%, a sufficient effect cannot be obtained, and if the addition amount is more than 5.0 mass%, the conductivity is lowered. Within the above range, the addition amount of Ni is 1.5 to 2.5 mass%, the addition amount of P is 0.3 to 0.5 mass%, and the addition amount of Zn is 0.1 to 2.0 mass%. When set to%, the above-described effect becomes remarkable.
[0016]
【Example】
Hereinafter, the manufacturing method of the copper alloy material for electronic devices of this invention is demonstrated in detail.
[0017]
Samples 1 to 15 of Examples and Comparative Examples were manufactured based on the manufacturing conditions shown in Table 2 for copper alloys having composition symbols A to D having the compositions shown in Table 1.
[0018]
[Table 1]

[Table 2]

[0019]
Here, the manufacturing procedure of the sample 1 will be described. First, a copper alloy having a composition symbol A shown in Table 1 using oxygen-free copper as a base material was melted in a high-frequency melting furnace to cast an ingot having a diameter of 30 mm and a length of 250 mm. Next, this was heated to 850 ° C. and extruded to form a plate having a width of 20 mm and a thickness of 8 mm, and then cold-rolled to a thickness of 0.7 mm. Subsequently, the cold-rolled copper alloy was heated to 800 ° C. and held for 10 minutes, and then poured into water and rapidly cooled to form a solution. Then, this was cold-rolled at a processing rate of 70% to a thickness of 0.21 mm, and then subjected to a first aging treatment that was held at 470 ° C. for 1 hour. Furthermore, the first aging treatment copper alloy was cold-rolled at a processing rate of 30% to a thickness of 0.15 mm, and then subjected to a second aging treatment that was held at 400 ° C. for 1 hour. Example 1 was obtained.
[0020]
Samples 2 and 3 which are examples and samples 4 to 11 which are comparative examples have a solution treatment temperature and a cold treatment after solution treatment with respect to a copper alloy having the composition of symbol composition A shown in Table 1. Similar to sample 1, changing the hot rolling processing rate, the temperature of the first aging treatment, the cold rolling processing rate after the first aging treatment, and the temperature of the second aging treatment as shown in Table 2. Manufactured.
[0021]
Further, Sample 12 as an example was manufactured by subjecting a copper alloy having the composition of symbol composition B shown in Table 1 to each treatment under the same conditions as Sample 1.
[0022]
Furthermore, samples 13 to 15 as comparative examples were manufactured by subjecting copper alloys having the compositions of symbolic compositions C, D, and E shown in Table 1 to the same conditions as in sample 1.
[0023]
Next, the tensile strength, electrical conductivity, and crystal grain size of samples 1 to 15 obtained in this manner were measured. Table 3 shows the measurement results.
[Table 3]

As is apparent from Table 3, Samples 1 to 3 and Sample 12, which are examples, have good strength and electrical conductivity, and refinement of crystal grain size, that is, improvement of micro workability by etching is achieved. Has been.
[0024]
On the other hand, Samples 4 and 5 are comparative examples in which the solution treatment temperature is out of the range of the present invention. Sample 4 with a high treatment temperature has larger crystal grains, sample 5 with a low treatment temperature has good strength, and Conductivity is not obtained. Sample 6 is a comparative example in which the processing rate of the cold rolling after the solution treatment is lower than the range of the present invention, and the refinement of crystal grains is insufficient. Samples 7 and 8 are comparative examples in which the temperature of the first aging treatment is out of the range of the present invention, and the strength is insufficient. Sample 9 is a comparative example in which the processing rate of cold rolling after the first aging treatment is higher than the range of the present invention, and the strength is insufficient. Samples 10 and 11 are comparative examples in which the temperature of the second aging treatment is out of the range of the present invention. The sample 10 with a low treatment temperature has insufficient conductivity, and the sample 11 with a high treatment temperature has strength and Crystal grain refinement is insufficient. Samples 13 to 15 are comparative examples in which the alloy composition deviated from the scope of the present invention, and all of them were insufficient in strength and conductivity.
[0025]
The copper alloy materials for electronic devices according to the embodiments described above are excellent in mechanical strength, electrical / thermal conductivity, and fine workability by etching, and are therefore suitable as lead frames for smaller and multi-pin semiconductor devices. Can be a material.
[0026]
【The invention's effect】
As described above, according to the method for producing a copper alloy material for electronic equipment of the present invention, after a solution treatment of a copper alloy containing Ni and P, cold working and aging treatment are each repeated twice, and Since the temperature of the solution treatment, the processing rate of cold working, and the temperature of aging treatment are set to predetermined values, it is possible to improve the fine workability by etching, mechanical strength, and electrical / thermal conductivity.

Claims

1.0 to 4.0 mass% of Ni and 0.2 to 0.8 mass% of P are contained in a mass ratio of 4 to 6, and 0.1 to 5.0 mass% of Zn is contained as an accessory component, Cast the copper alloy material consisting of the remaining Cu,
The copper alloy material is subjected to a solution treatment at 750 to 900 ° C.,
The copper alloy material that has undergone the solution treatment is subjected to a first cold working with a processing rate of 60% or more,
The copper alloy material subjected to the first cold working is subjected to a first aging treatment at 400 to 500 ° C. for 30 minutes to 3 hours,
A second cold working with a processing rate of 50% or less is applied to the copper alloy material that has been subjected to the first aging treatment,
A method for producing a copper alloy material for electronic equipment, comprising subjecting the copper alloy material that has undergone the second cold working to a second aging treatment at 350 to 500 ° C. for 30 minutes to 3 hours.