WO2019041587A1 - 一种电子封装用高可靠性铜合金键合丝及其制备方法 - Google Patents

一种电子封装用高可靠性铜合金键合丝及其制备方法 Download PDF

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WO2019041587A1
WO2019041587A1 PCT/CN2017/112638 CN2017112638W WO2019041587A1 WO 2019041587 A1 WO2019041587 A1 WO 2019041587A1 CN 2017112638 W CN2017112638 W CN 2017112638W WO 2019041587 A1 WO2019041587 A1 WO 2019041587A1
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copper alloy
bonding wire
copper
purity
wire
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PCT/CN2017/112638
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English (en)
French (fr)
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袁斌
罗政
朱敏
徐云管
彭庶瑶
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华南理工大学
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Priority to US16/642,971 priority Critical patent/US20200373272A1/en
Publication of WO2019041587A1 publication Critical patent/WO2019041587A1/zh

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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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    • C22C9/00—Alloys based on copper
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Definitions

  • the invention relates to a copper alloy bonding wire, in particular to a high reliability copper alloy bonding wire for electronic packaging and a preparation method thereof, which are used for an electronic integrated circuit (IC) and a semiconductor discrete device (such as LED) post-packaging process.
  • IC electronic integrated circuit
  • LED semiconductor discrete device
  • IC and LED lead material bonding is a way to realize the electrical connection of various circuits of the circuit chip pre-packaged casing, and to transmit the electrical signal of the chip and dissipate the heat generated in the chip.
  • the most common, simple and effective one way, so the bonding wire It has become one of the four important structural materials for the electronic packaging industry.
  • IC packaging is rapidly moving toward small size, high strength, high density, multi-layer chips, and low-cost direction, so that the requirements for IC package lead materials are extremely fine (diameter 0.018mm, even 0.015mm), high mechanical properties (high breaking strength and good elongation), excellent bonding properties and bonding reliability; at the same time, LED packaging is also rapidly moving toward high power, low cost and high Intensive development, it is also required to encapsulate the bond wire with ultra-fine, high performance (high conductivity and thermal conductivity), low price and other characteristics.
  • the most widely used lead-bonded bonding wires for ICs, semiconductor discrete devices and the like are gold and silver bonding wires. Because gold and silver are precious metals, they are expensive and growing, putting heavy cost pressure on the most used low-end LED and IC package users.
  • the traditional gold wire has gradually approached the limit in terms of electrical and thermal conductivity, and it has been unable to meet the requirements of narrow pitch, low arc, long arc and high power bonding specifications in the bonding process. Therefore, the industry is in urgent need of a new type of bonding wire material which is relatively inexpensive, stable and reliable, and is used to replace gold and silver bonding wires.
  • copper wire has higher electrical and thermal conductivity than gold wire, can be used to manufacture power devices with higher current load requirements, and can make heat dissipation in high-density packaging easier.
  • the stronger tensile strength of the copper wire can make the wire diameter thinner, the pad size and the pad pitch can be reduced accordingly, and the price is 90% cheaper than the precious metal bonding wire.
  • the high temperature oxidation of copper, high hardness, and corrosion of the surface of the wire during resin encapsulation are the most concerned shortcomings.
  • the resulting pure copper wire bond requires more stringent bonding process parameters and a narrower process window than gold wire bonding, such as when a protective gas (95% N 2 + 5% H 2 ) is used to prevent ball formation.
  • a protective gas (95% N 2 + 5% H 2
  • the surface coating is mainly made of palladium on the surface of pure copper bonding wire, the core of the copper wire is 99.9999% copper, and the palladium plating process is vacuum coating.
  • the distribution and thickness of the palladium layer are crucial for the reliability of the copper bonding wire. This causes a great increase in the complexity of the preparation process, and at the same time, since palladium is a precious metal, the price is high, and the cost of the palladium-plated pure copper bonding wire is also greatly increased.
  • the purpose of palladium plating is to insulate the contact between the copper wire and the air, and reduce the oxidation rate.
  • the palladium layer and the substrate copper wire have different recrystallization temperatures, which are prone to defects such as smashing. Process.
  • Alloying is to improve the oxidation resistance and spheroidality of copper wire by adding a small amount of alloying elements to form a uniform copper alloy, reduce hardness, improve strength, etc., without losing the electrical and thermal conductivity of copper.
  • the main direction of the copper bond wire most of the copper alloy bond wires reported so far are focused on improving the oxidation resistance and strength of copper alloy bond wires. None of the main disadvantages of copper alloy bond wires can be improved, including oxidation resistance and corrosion resistance. Sex and high hardness. Some improve their oxidation resistance, and the strength is also high; but the plasticity is poor, can not be continuously drawn into the filament, and the corrosion resistance is also poor, so the bonding reliability is poor. It is possible that the prior art copper alloy bonding wires only consider the addition of alloying elements to improve oxidation resistance and strength, without considering the addition of elements to improve corrosion resistance and bonding reliability, and also from the synthesis of microstructure and alloy composition. consider.
  • the object of the present invention is to overcome the above deficiencies of the prior art, and to provide a copper alloy bonding wire for electronic packaging and a preparation method thereof, which overcomes the problem that the surface of the existing copper alloy bonding wire is easy to be oxidized, has poor corrosion resistance, and is broken. And key issues such as poor reliability.
  • the invention relates to a high-reliability copper alloy bonding wire for electronic packaging, wherein the composition of the raw material is composed of a copper content of 99.75%-99.96%, a tungsten content of 0.01-0.1%, a silver content of 0.01%-0.03%, and a cerium content. 0.01%-0.02%, titanium content 0.001%-0.03%, chromium content 0.001%-0.03%, iron content 0.001%-0.02%, unavoidable impurities, and impurities in the S and O throughout the copper alloy bond
  • the content in the yarn is ⁇ 10 wt. ppm, and the sum of all element contents is equal to 100%.
  • the purity of copper in the feedstock is greater than 99.99%.
  • the raw material requires that the purity of any of tungsten, silver, ruthenium, iron, titanium and chromium is greater than 99.999%.
  • the method for preparing a high reliability copper alloy bonding wire for electronic packaging comprises the following steps:
  • step 2) preparing a copper alloy ingot: adding high-purity copper obtained in step 1) to tungsten, silver, lanthanum, iron, titanium, chromium, mixing and heating and melting under argon gas protection conditions to prepare a copper alloy ingot;
  • Homogenization annealing The ⁇ 4- ⁇ 6mm as-cast copper alloy bar is homogenized and annealed, the annealing temperature is controlled at 600-900 ° C, the annealing time is 6-10 hours, and the protective atmosphere is 95% N 2 +5% H. 2 , the process of cooling to room temperature has been introduced into the protective gas;
  • Fine drawing precision drawing of the heat-treated copper alloy wire into a finished copper alloy bonding wire having a diameter of 15 ⁇ m to 50 ⁇ m;
  • the high purity copper of step 1) has an impurity S and O content of less than 5 wt. ppm.
  • the mixing described in step 2) is mechanical mixing.
  • the heating and melting described in step 2) is carried out in a high purity graphite crucible, and the heating and melting is performed using an electric arc furnace.
  • the heating and melting described in step 3) is the application of intermediate frequency induction heating.
  • the surface cleaning described in step 9) first cleans the bonding wire with the diluted acid solution, and then ultrasonically cleans and then rinses with high purity water.
  • the finished copper alloy bonding wire is further wound, divided and packaged.
  • adding a certain amount of tungsten (W) element to copper can greatly increase the oxidation resistance, corrosion resistance and strength of the copper alloy, and refine the crystal grains when ball bonding into balls, thereby ensuring bonding strength and Reliability; adding a certain amount of silver (Ag) element to copper can increase the oxidation resistance of copper alloy and ensure the electrical and thermal conductivity of copper alloy; adding a certain amount of strontium (Sc) to copper can greatly affect the structure of copper alloy. And the performance can greatly improve the strength of the copper alloy, and also maintain the plasticity of the alloy, and it is excellent in corrosion resistance and spheroidality (welding property).
  • bismuth is both a rare earth metal and a transition metal, it has both a rare earth element in the copper alloy. It also improves the role of ingot structure and has the role of recrystallization inhibitor of transition elements.
  • the main effect of adding a small amount of titanium (Ti) to copper is to reduce the amount of addition of Sc, reduce the cost of the alloy, and at the same time produce a strong metamorphism and inhibit recrystallization ability.
  • the addition of trace amounts of chromium (Cr) to copper increases the corrosion resistance, electrical conductivity and strength of the copper alloy.
  • the addition of a small amount of iron (Fe) to the copper further ensures the electrical conductivity of the copper alloy, reduces the hardness, and ensures the bonding reliability of the bonding wire and the different pad materials.
  • Silver, bismuth, titanium, chromium and iron can all be dissolved into copper to form a solid solution.
  • tungsten and copper do not dissolve in each other, but the addition of titanium or chromium can form a complete solid solution with tungsten, thereby ensuring that all tungsten solid solution enters the copper alloy, forming a single crystal structure, reducing the existence of grain boundaries, thereby reducing the hardness of the copper alloy, Improve conductivity and thermal conductivity; while adding titanium and chromium is mainly to reduce the amount of individual elements added to ensure the conductivity and strength of the copper alloy. The price of the added elements is not expensive, thus reducing the cost of the copper alloy bond wires.
  • the added alloying elements can ensure the copper alloy conductive (Ag, Fe), oxidation resistance (W, Ag) and strength (W), and increase the resistance thereof.
  • W, Cr Corrosive
  • W, Sc, Ti, Fe bonding reliability
  • the single crystal structure is formed, and Ti and Cr elements are intentionally added to solid-dissolve the W element, thereby obtaining a single crystal copper alloy bonding wire. Since no grain boundary exists, the hardness thereof is lowered, and electrical conductivity, heat conduction and plasticity are ensured.
  • the present invention has the following advantages:
  • the copper alloy bonding wire for electronic packaging of the present invention has good oxidation resistance and spheroidality, and excellent corrosion resistance (permeability failure rate is less than 5%, which is 100% higher than that of the existing copper alloy bonding wire) High bonding reliability (through all reliability tests), high conductivity (minimum fuse current 0.28A to 0.3A, 20% higher than general copper alloy bonding wire 0.23A) and thermal conductivity, high strength (6 -11.5cN, 50% higher than existing copper alloy bond wires) and good plasticity (14.6-18%, more than 12% higher than existing copper alloy bond wires);
  • the copper alloy bonding wire for electronic packaging of the present invention can meet the requirements of high performance, multifunction, miniaturization, and low cost of electronic packaging.
  • Fig. 1 is a top view showing the solder joints of the copper alloy bonded wire ball of the first embodiment.
  • the examples relate to the testing of performance parameters, the reference standard being YS/T 678-2008 (copper wire for semiconductor device bonding) and GB/T 8750 (key alloy wire for semiconductor packaging).
  • the tensile strength and elongation test method is GB/T 10573 (non-ferrous metal filament tensile test method), and the bonding strength test method refers to the US MIL-STD 883G test standard (Test method standard) Microcircuits, 2006), reliability test methods refer to the Wire Bonding Quality Assurance and Testing Methods (DTRamelow) and the conventional reliability test methods for the electronics packaging industry.
  • a copper alloy bonding wire with high purity copper as a main material the material constituting the bonding wire is composed of the following raw materials by weight: tungsten (W) content is 0.1%, silver (Ag) content is 0.020%, ⁇ (Sc) content is 0.013%, titanium (Ti) content is 0.03%, chromium (Cr) content is 0.03%, iron (Fe) content is 0.01%, and the content of S and O in the entire copper alloy bond wire is ⁇ 10wt.ppm, the balance is copper and unavoidable impurities, the sum is equal to 100%; the purity of copper is required to be greater than 99.99%, and the purity of tungsten, silver, antimony, iron, titanium and chromium is greater than 99.999%.
  • the preparation steps and methods for preparing the copper alloy single crystal bonding wire for microelectronic packaging are as follows:
  • the ⁇ 6mm as-cast copper alloy bar is homogenized and annealed; the annealing temperature is 900 ° C, the annealing time is 6 hours, the protective atmosphere is 95% N 2 + 5% H 2 , and the process is cooled to room temperature. Always enter the protective gas;
  • Heat treatment A copper alloy wire having a diameter of 1 mm was annealed; the annealing temperature was 600 ° C, the annealing time was 2 hours, and the protective atmosphere was 95% N 2 + 5% H 2 .
  • Fine extraction The annealed copper alloy wire was precisely drawn into a copper alloy single crystal bond wire having a diameter of 18 ⁇ m.
  • Sub-volume The copper alloy single crystal bond wire for the finished microelectronic package is rewinded, divided and packaged.
  • the copper alloy bond wire has a breaking force of 5.96 ⁇ 0.16cN (standard specification >5cN, which is more than 20% higher than the standard), and the elongation is 14.62 ⁇ 0.82% (standard specification is 4-10%, the elongation ratio is higher than the prior art)
  • the material is increased by more than 45%), the minimum fusing current is 0.28A (standard is 0.23A or more qualified, and the increase is more than 20%), which indicates that it has good electrical conductivity, high strength, good ductility, and can continuously pull 10,000 meters.
  • Continuous line (standard is 5000m continuous line, 100% higher than the standard), this is mainly due to the addition of W and Sc elements to enhance the strength of the bonding wire, adding Ag and Fe to ensure the conductivity of the bonding wire, while adding Sc and the formation of a single crystal structure to ensure its excellent ductility. After 23,000 welds, the break was only once, indicating that it has good ductility.
  • the copper alloy bonding wire has moderate hardness and good sphericality, as shown in FIG.
  • the bond strength test results show that the ball joint thrust is 18-26g (required to be no less than 14g, increase by more than 14%), and the tensile force is 5-10g (required to be no less than 4.5g, increase by more than 11%), all meet the requirements. .
  • the reliability test items include: plate reflow soldering (1870 samples, test pass), storage test (1600 samples, test pass), high temperature and high humidity (1600 samples, pass), high temperature cooking ( The number of samples is 100, the test passes), the airtightness (100 samples, 5 infiltration, the non-quantity rate is 5%. The defect rate is 10% or less for the test pass, and the increase is 100% or more).
  • Good bonding strength and bonding reliability are due to the addition of W, Sc and Ti elements to suppress the recrystallization temperature of ball joints during ball bonding, refine grains, greatly increase bond strength, and add W and Cr elements. It can greatly improve its corrosion resistance.
  • the copper alloy bonding wire of this embodiment has good oxidation resistance and spheroidality, high strength, good plasticity, excellent corrosion resistance, high bonding strength and high bonding reliability, and is very suitable for high density. Multi-pin, low cost integrated circuits and LED packages.
  • a copper alloy bonding wire with high purity copper as a main material the material constituting the bonding wire is composed of the following raw materials by weight: tungsten (W) content is 0.05%, silver (Ag) content is 0.025%, ⁇ (Sc) content of 0.015%, titanium (Ti) content of 0.02%, chromium (Cr) content of 0.01%, iron (Fe) content of 0.015%, and the content of S and O in the entire copper alloy bond wire ⁇ 10wt.ppm, the balance is copper and unavoidable impurities, the sum is equal to 100%; the purity of copper is required to be greater than 99.99%, and the purity of tungsten, silver, antimony, iron, titanium and chromium is greater than 99.999%.
  • the preparation steps and methods for preparing the copper alloy single crystal bonding wire for microelectronic packaging are as follows:
  • the ⁇ 4mm as-cast copper alloy bar is homogenized and annealed; the annealing temperature is 800 ° C, the annealing time is 8 hours, the protective atmosphere is 95% N 2 + 5% H 2 , and the temperature is cooled to room temperature. Access to protective gas;
  • Heat treatment A copper alloy wire having a diameter of 0.5 mm was annealed; the annealing temperature was 550 ° C, the annealing time was 4 hours, and the protective atmosphere was 95% N 2 + 5% H 2 .
  • Fine drawing The annealed copper alloy wire is precisely drawn into a copper alloy single crystal bonding wire having a diameter of 20 ⁇ m.
  • Sub-volume The copper alloy single crystal bond wire for the finished microelectronic package is rewinded, divided and packaged.
  • the copper alloy single crystal bond wire has a breaking force greater than 8cN (standard is >6cN, which is more than 30% higher than the standard), and the elongation is greater than 15% (standard is 6-12%, more than 25% higher than the standard), minimum blown
  • the current is 0.29A (standard is 0.24A, more than 20% higher than the standard), and the hardness is moderate, the welding is good, it is very suitable for high-density, multi-pin integrated circuit package.
  • a copper alloy bonding wire with high purity copper as a main material the material constituting the bonding wire is composed of the following raw materials by weight: tungsten (W) content is 0.01%, silver (Ag) content is 0.03%, ⁇ (Sc) content is 0.02%, titanium (Ti) content is 0.001%, chromium (Cr) content is 0.01%, iron (Fe) content is 0.02%, and the content of S and O in the entire copper alloy bonding wire is ⁇ 10wt.ppm, the balance is copper and unavoidable impurities, the sum is equal to 100%; the purity of copper is required to be greater than 99.99%, and the purity of tungsten, silver, antimony, iron, titanium and chromium is greater than 99.999%.
  • the preparation steps and methods for preparing the copper alloy single crystal bonding wire for microelectronic packaging are as follows:
  • the ⁇ 5mm as-cast copper alloy bar is homogenized and annealed; the annealing temperature is 750 ° C, the annealing time is 10 hours, the protective atmosphere is 95% N 2 + 5% H 2 , and the temperature is cooled to room temperature. Pass in protective gas.
  • Heat treatment A copper alloy wire having a diameter of 1 mm was annealed; the annealing temperature was 500 ° C, the annealing time was 6 hours, and the protective atmosphere was 95% N 2 + 5% H 2 .
  • Fine drawing The annealed copper alloy wire is precisely drawn into a copper alloy single crystal bonding wire having a diameter of 25 ⁇ m.
  • Sub-volume The copper alloy single crystal bond wire for the finished microelectronic package is rewinded, divided and packaged.
  • the copper alloy single crystal bond wire has a breaking force greater than 11.5 cN (standard is >8 cN, which is more than 30% higher than the standard), and the elongation is greater than 18% (standard is 8-16%, more than 12% higher than the standard), and the minimum
  • the fuse current is 0.3A (standard is 0.26A, more than 7% higher than the standard), and the hardness is moderate, the welding is good, it is very suitable for high-density, multi-pin integrated circuit package.

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Abstract

一种电子封装用高可靠性铜合金键合丝及其制备方法，该键合丝的原料成分重量百分比组成为：铜含量为99.75％‐99.96％、钨含量为0.01‐0.1％、银含量为0.01％‐0.03％、钪含量为0.01％‐0.02％、钛含量为0.001％‐0.03％、铬含量为0.001％‐0.03％、铁含量为0.001％‐0.02％。其制备方法包括：提取纯度大于99.99％的高纯铜，制备成铜合金铸锭，再制成铸态铜合金母线，将母线拉制成铜合金丝经热处理后，再经精密拉拔、热处理、清洗后制成不同规格的铜合金键合丝。

Description

一种电子封装用高可靠性铜合金键合丝及其制备方法 技术领域
本发明涉及铜合金键合丝，特别是涉及一种电子封装用高可靠性铜合金键合丝及其制备方法，该铜合金键合丝用于电子集成电路(IC)和半导体分立器件(如LED)后道封装工序。
背景技术
现代社会中，随着科技和电子信息技术的飞速发展，几乎所有现代化的产品中，都会用到电子元器件，大到军用卫星、导弹、雷达等，以及家用的汽车、电视、电脑、洗衣机、冰箱等，小到手机、导航设备、各种磁卡、可穿戴设备、LED灯照明等。绝大部分的产品都是基于集成电路(IC)和半导体元器件。IC和半导体分立器件又是电子信息产品的发展基础，在IC的芯片与外部引线，以及LED封装中半导体芯片与电极的连接方法中，采用键合线仍是芯片连接(或称引线键合)的主要技术手段。IC和LED引线材料键合是实现电路芯片预封装外壳多种电路电连接，并传递芯片的电信号、散发芯片内产生的热量，最通用、最简单而有效的一种方式，所以键合引线已成为电子封装产业四大重要结构材料之一。
随着微电子工业和LED照明产业的蓬勃发展，IC封装正快速的朝着体积小，高强度，高密集，多层芯片，低成本方向推进，从而对IC封装引线材料的要求特细(直径0.018mm，甚至0.015mm)、高的力学性能(高断裂强度和良好延伸率)、优良的键合性能和键合可靠性；与此同时，LED封装也迅速地向着高功率、低成本、高密集方向发展，因此也要求封装键合线具有超细、高性能(高的导电和导热性能)、低价格等特性。
目前用于IC、半导体分立器件等领域的引线封装键合丝最为广泛采用的是黄金和白银类键合丝。由于黄金和白银属贵重金属，价格昂贵且日益上涨，给用量最大的中低端LED、IC封装用户带来沉重的成本压力。传统的金丝已经在导电和导热性能上逐步趋近于极限，在键合工艺中已不能胜任窄间距、低弧度、长弧距、高功率键合技术指标的要求。因而业界急需成本相对低廉、性能稳定可靠的新型键合丝材料用以取代黄金和银键合丝。
铜丝作为内引线，具有比金丝高的导电和导热性能，可以用于制造对电流负载要求更高的功率器件，而且可以使高密度封装时的散热更为容易。铜丝较强的抗拉强度可以使丝线直径变得更细，焊盘尺寸和焊盘间距也能相应减小，价格比贵金属键合丝材便宜90％以上。但铜的高温易氧 化性、高硬度以及进行树脂封装时易引起线材表面腐蚀是人们最为关注的缺点。因而，造成纯铜线键合比金线键合需采用更严苛的键合工艺参数和更窄的工艺窗口，诸如采用保护气体(95％N2+5％H2)防止成球时的表面氧化、更高键合力和超声能量等，以保证键合的可靠性。目前，研发铜键合丝的主要两个方向：高纯铜丝表面涂层和合金化。
表面涂层主要采用纯铜键合线表面镀钯，铜丝芯材为99.9999％铜，镀钯工艺为真空镀膜，这一钯层的分布和厚度对于铜键合线的可靠性至关重要，这造成制备工艺的复杂性大为增加，同时由于钯为贵金属，价格较高，因而造成镀钯纯铜键合线成本也大为增加。而且，镀钯的目的是隔绝铜丝与空气的接触，降低其氧化速率，但在烧球键合过程中，由于镀钯层与基材铜丝的再结晶温度不同，容易发生歪球等不良工艺。
合金化则是通过添加微量合金元素形成均匀的铜合金来改善铜线的抗氧化性和成球性，降低硬度，提高强度等，但又不损失铜的导电导热性，这是目前研发高质量铜键合丝的主要方向。然而，目前报道的铜合金键合丝，大多数关注于改善铜合金键合丝的抗氧化性能和强度，没有一种能够改善铜合金键合丝的所有主要缺点，包括抗氧化性、耐腐蚀性和高硬度。有的改善其抗氧化性，且强度也较高；但塑性较差，不能连续拉成细丝，同时耐腐蚀性也较差，因此其键合可靠性较差。可能主要是现有技术的铜合金键合丝只考虑添加合金元素来改善抗氧化性和提高强度，没有考虑添加元素来提高耐腐蚀性和键合可靠性，也没有从微观结构和合金成分综合考虑。
发明内容
本发明的目的是克服以上现有技术不足，提供一种电子封装用铜合金键合丝及其制备方法，它克服现有铜合金类键合丝表面易氧化、耐腐蚀性差、拉拔断线和可靠性差等关键问题。
本发明为解决其技术问题所采用的技术方案是：
一种电子封装用高可靠性铜合金键合丝，其原料成分重量百分比组成为：铜含量为99.75％-99.96％、钨含量为0.01-0.1％、银含量为0.01％-0.03％、钪含量为0.01％-0.02％、钛含量为0.001％-0.03％、铬含量为0.001％-0.03％、铁含量为0.001％-0.02％，不可避免的杂质，且杂质中S和O在整个铜合金键合丝中的含量≤10wt.ppm，全部元素含量之和等于100％。
优选地，所述原料中铜的纯度大于99.99％。
优选地，所述原料中要求钨、银、钪、铁、钛和铬任一种的纯度都大于99.999％。
所述的电子封装用高可靠性铜合金键合丝的制备方法，包括如下步骤：
1)提取高纯铜：铜材料经电镀后，提取纯度大于99.9999％的高纯铜，再经清洗、烘干，备用；
2)制备成铜合金铸锭：步骤1)所得高纯铜中加入钨、银、钪、铁、钛、铬，混合后在氩气保护条件下加热熔化，制备成铜合金铸锭；
3)连铸成铸态铜合金棒材：将制备好的铜合金铸锭加入有氮气保护的金属水平连铸室，加热熔化、精炼和除气后，将熔液注入储液池保温，完成对铜合金熔液的水平连铸，得到Φ4-Φ6mm的铸态铜合金棒材；
4)均匀化退火：将Φ4-Φ6mm的铸态铜合金棒材进行均匀化退火，控制退火温度为600-900℃，退火时间为6-10小时，保护气氛为95％N2+5％H2，冷却至室温过程一直通入保护气；
5)粗拔：将均匀化退火后的Φ4-Φ6mm铸态铜合金棒材拉拔成Φ2-Φ3mm铜合金棒材，再拉拔成直径为0.5-1mm的铜合金丝；
6)热处理：将直径为0.5-1mm的铜合金丝进行中间退火，退火温度为400-600℃，退火时间为2-6小时，保护气氛为95％N2+5％H2；
7)精拔：对经热处理后的铜合金丝精密拉拔成直径分别为15μm-50μm的成品铜合金键合丝；
8)热处理：将精拔后的铜合金单晶键合丝进行退火，退火温度为400-600℃，退火时间为0.2-0.6秒，保护气氛为95％N2+5％H2；
9)表面清洗，烘干，得成品铜合金键合丝。
优选地，步骤1)所述的高纯铜中杂质S和O含量小于5wt.ppm。
优选地，步骤2)所述的混合为机械混合。
优选地，步骤2)所述的加热熔化是高纯石墨坩埚中进行，加热熔化是使用电弧炉加热。
优选地，步骤3)所述的加热熔化是应用中频感应加热。
优选地，步骤9)所述的表面清洗先用稀释后的酸液对键合丝进行清洗，然后经超声波清洗，再经高纯水清洗。
优选地，步骤9)所述的表面清洗、烘干后还包括将成品铜合金键合丝进行复绕、分卷、包装。
本发明的原理：向铜中添加一定量钨(W)元素，可大幅度增加铜合金的抗氧化性、耐腐蚀性和强度，以及球焊成球时细化晶粒，保证键合强度和可靠性；向铜中添加一定量银(Ag)元素可增加铜合金的抗氧化性，保证铜合金的导电和导热性；向铜中一定量添加钪(Sc)能极大地影响铜合金的组织和性能，可大幅地提高铜合金的强度，还能保持合金的塑性，且其耐腐蚀性和成球性(焊接性能)优异。因为钪既是稀土金属又是过渡族金属，它在铜合金中既有稀土元素的净 化和改善铸锭组织的作用，又有过渡族元素的再结晶抑制剂作用。向铜中添加微量的钛(Ti)的主要作用是降低Sc的添加量，降低合金的成本，同时产生很强的变质作用和抑制再结晶能力。向铜中添加微量的铬(Cr)可以增加铜合金的耐腐蚀性、导电性和强度。向铜中添加微量的铁(Fe)可以进一步保证铜合金的导电性，降低硬度，保证键合丝与不同焊盘材料的键合可靠性。银、钪、钛、铬和铁都能固溶进入铜形成固溶体。但钨与铜互不固溶，但是添加钛或铬可以与钨形成完全固溶体，从而保证全部的钨固溶进入铜合金中，形成单晶组织，减少晶界存在，从而降低铜合金的硬度，提高导电和导热性；同时添加钛和铬主要是减少单个元素的添加量，保证铜合金的导电性和强度。所添加元素的价格均不贵，因此降低铜合金键合丝的成本。
本发明在合金成分和微观结构上的综合考虑是添加的合金元素能够保证铜合金导电(Ag、Fe)、抗氧化性(W、Ag)和强度(W)的基础上，添加了增加其耐腐蚀性(W、Cr)和键合可靠性(W、Sc、Ti、Fe)的微量元素，同时为了增加铜合金键合丝的塑性，特意添加了Sc元素；而且为了保证铜合金键合丝形成单晶组织，有意添加Ti和Cr元素，来固溶W元素，从而获得单晶的铜合金键合丝，由于没有晶界存在，其硬度降低，导电、导热和塑性得到保证。
相对于现有技术，本发明具有以下优点：
1)本发明的电子封装用铜合金键合丝具有良好抗氧化性和成球性、优异的耐腐蚀性(渗透性不良率低于5％，比现有铜合金键合丝提升100％)、高的键合可靠性(通过全部的可靠性测试)、高导电(最小熔断电流0.28A～0.3A，比一般铜合金键合丝0.23A提高20％以上)和导热性、高强度(6-11.5cN，比现有铜合金键合丝提高50％)和良好的塑性(14.6-18％，比现有铜合金键合丝提高12％以上)；
2)本发明的电子封装用铜合金键合丝能够适应电子封装高性能、多功能、微型化、低成本的需求。
附图说明
图1为采用实施例1铜合金键合丝球焊时焊点的形貌图。
具体实施方式
为更好地支持本发明，下面结合附图和实施例对本发明作进一步的说明，但本发明的实施方式不限如此。
实施例涉及性能参数的测试，参照标准为YS/T 678-2008(半导体器件键合用铜丝)和GB/T 8750(半导体封装用键合金丝)。拉断力和延伸率测试方法为GB/T 10573(有色金属细丝拉伸实验方法)，键合强度的测试方法参考美国MIL-STD 883G测试标准(Test method standard  microcircuits,2006)，可靠性测试方法参照美国键合线质量保证和测试方法(Wire bonding quality assurance and testing methods,D.T.Ramelow)和电子封装行业常规可靠性测试方法，具体测试项目包括贴板回流焊(170±5℃～260±5℃，7分钟，100个循环)，存储测试(-40℃～100℃，1000小时)，高温高湿(85℃±5℃，85％RH，1000小时)，高温蒸煮(高压锅蒸50分钟，然后冷却5分钟，至-40℃冷藏50分钟为1个循环，1000循环)，气密性(红墨水兑水＝1:1，热板50℃)。
实施例1
一种以高纯铜为主体材料的铜合金键合丝，组成该键合丝的材料由下列重量百分比的原材料组成：钨(W)含量为0.1％，银(Ag)含量为0.020％、钪(Sc)含量为0.013％、钛(Ti)含量为0.03％，铬(Cr)含量为0.03％、铁(Fe)含量为0.01％，且S和O在整个铜合金键合丝中的含量≤10wt.ppm，其余为铜和不可避免的杂质，之和等于100％；要求铜的纯度大于99.99％，钨、银、钪、铁、钛和铬的纯度都要大于99.999％。
微电子封装用铜合金单晶键合丝的制备工艺步骤和方法如下：
(1)提取高纯铜：将TU00铜(99.99％铜)作为阳极浸入电解液中，以高纯铜箔作为阴极浸入电解液中；在阳极、阴极之间输入9V、2.5A的直流电，以补充新鲜电解液方式维持电解液温度不超过60℃，待阴极积聚一定重量的纯度大于99.9999％的高纯铜时及时更换高纯铜箔，再经清洗、烘干备用。
(2)制备成铜合金铸锭：提取纯度大于99.9999％的高纯铜，高纯铜中杂质S和O含量小于5wt.ppm，然后加入钨、银、钪、铁、钛和铬；其成分含量按照重量百分比分别为：钨占0.1％，银占0.02％、钪占0.013％、钛占0.03％，铬占0.03％，铁占0.01％，其余为铜和不可避免的杂质，之和等于100％。这些金属经机械混合后放入高纯石墨坩埚中，在氩气保护条件下使用电弧炉加热使其熔化，进而制备成铜合金铸锭。
(3)连铸成铸态铜合金棒材：将制备好的铜合金铸锭加入有氮气保护的水平连铸金属连铸室，应用中频感应加热至1300℃，待完全熔化、精炼和除气后，将熔液注入连铸室中间的储液池保温，在维持5L/min净化氮气流量的连铸室中，完成对铜合金熔液的水平单晶连铸，得到Φ6mm的铸态铜合金棒材。
(4)均匀化退火：将Φ6mm的铸态铜合金棒材进行均匀化退火；退火温度为900℃，退火时间为6小时，保护气氛为95％N2+5％H2，冷却至室温过程一直通入保护气；
(5)粗拔：将均匀化退火后的Φ6mm的铸态铜合金棒材拉拔成Φ3mm铜合金棒材，接着继续拉拔成直径为1mm的铜合金丝。
(6)热处理：将直径为1mm的铜合金丝进行退火处理；退火温度为600℃，退火时间为2小时，保护气氛为95％N2+5％H2。
(7)精拔：将经退火处理的铜合金丝精密拉拔成直径18μm铜合金单晶键合丝。
(8)热处理：将精拔后的铜合金键合丝进行退火处理；退火温度为450℃，退火时间为0.3秒，保护气氛为95％N2+5％H2，退火完成后，得到电子封装用铜合金键合丝。
(9)表面清洗：将退火处理后的电子封装用铜合金单晶键合丝先经稀释后的酸液中进行清洗，然后经超声波清洗，再经高纯水清洗、烘干。
(10)分卷：将成品微电子封装用铜合金单晶键合丝进行复绕、分卷、包装。
该铜合金键合丝拉断力为5.96±0.16cN(标准规定>5cN，比标准提升20％以上)，延伸率为14.62±0.82％(标准规定为4-10％，延伸率比现有技术材料提升45％以上)，最小熔断电流为0.28A(标准规定为0.23A以上合格，提升20％以上)，表明其导电性好，且强度高，延展性好，可连续拉拔1万米而不断线(标准规定为5000m不断线，比标准提升100％)，这主要是由于添加了W和Sc元素提升了键合丝的强度，添加Ag和Fe保证键合丝的导电性，同时添加了Sc和形成单晶组织，保证其优良的延展性。经过2.3万次焊接，断线只有一次，表明其延展性良好。该铜合金键合丝的硬度适中，焊接成球性好，如图1所示，为采用该实施例的铜合金键合丝球焊时焊点形貌(球焊的参数：成球电流50mA，成球时间0.24s，焊接时间6s，焊接功率60-80W，焊接压力20cN，保护气为95％N2+5％H2)，其圆度非常好，没有发生偏心，表明铜合金键合丝的抗氧化性和成球性良好。这主要是由于添加W和Cr元素提升了铜合金键合丝的抗氧化性，同时添加Ti和Cr保证W固溶进入铜合金形成单晶固溶体组织，没有晶界存在，硬度降低。键合强度测试结果为，球焊点推力为18-26g(要求为不小于14g，提升14％以上)，拉力为5-10g(要求为不小于4.5g，提升11％以上)，都符合要求。所述可靠性测试项目包括：贴板回流焊(样品数量1870个，测试通过)，存储测试(样品数1600个，测试通过)，高温高湿(样品数1600个，测试通过)，高温蒸煮(样品数100个，测试通过)，气密性(样品数100个，渗透5个，不量率为5％。不良率10％以下为测试通过，提升100％以上)。良好的键合强度和键合可靠性是由于添加W、Sc和Ti元素可以抑制球焊时球焊点的再结晶温度，细化晶粒，大幅度提升键合强度，而且添加W和Cr元素可以大幅度提升其耐腐蚀性。
由上可知，该实施例的铜合金键合丝具有良好抗氧化性和成球性、强度高、塑性好、耐腐蚀性优异、且键合强度和键合可靠性高，非常适用于高密度、多引脚、低成本的集成电路和LED封装。
实施例2
一种以高纯铜为主体材料的铜合金键合丝，组成该键合丝的材料由下列重量百分比的原材料组成：钨(W)含量为0.05％，银(Ag)含量为0.025％、钪(Sc)含量为0.015％、钛(Ti)含量为0.02％，铬(Cr)含量为0.01％、铁(Fe)含量为0.015％，且S和O在整个铜合金键合丝中的含量≤10wt.ppm，其余为铜和不可避免的杂质，之和等于100％；要求铜的纯度大于99.99％，钨、银、钪、铁、钛和铬的纯度都要大于99.999％。
微电子封装用铜合金单晶键合丝的制备工艺步骤和方法如下：
(1)提取高纯铜：将TU00铜(99.99％铜)作为阳极浸入电解液中，以高纯铜箔作为阴极浸入电解液中；在阳极、阴极之间输入8V、3A的直流电，以补充新鲜电解液方式维持电解液温度不超过60℃，待阴极积聚一定重量的纯度大于99.9999％的高纯铜时及时更换高纯铜箔，再经清洗、烘干备用。
(2)制备成铜合金铸锭：提取纯度大于99.9999％的高纯铜，高纯铜中杂质S和O含量小于5wt.ppm，然后加入钨、银、钪、铁、钛和铬；其成分含量按照重量百分比分别为：钨占0.05％，银占0.025％、钪占0.015％、钛占0.02％，铬占0.01％、铁占0.015％，其余为铜和不可避免的杂质，之和等于100％。这些金属经机械混合后放入高纯石墨坩埚中，在氩气保护条件下使用电弧炉加热使其熔化，进而制备成铜合金铸锭。
(3)连铸成铸态铜合金棒材：将制备好的铜合金铸锭加入有氮气保护的水平连铸金属连铸室，应用中频感应加热至1200℃，待完全熔化、精炼和除气后，将熔液注入连铸室中间的储液池保温，在维持4L/min净化氮气流量的连铸室中，完成对铜合金熔液的水平单晶连铸，得到Φ4mm的铸态铜合金棒材。
(4)均匀化退火：将Φ4mm的铸态铜合金棒材进行均匀化退火；退火温度为800℃，退火时间为8小时，保护气氛为95％N2+5％H2，冷却至室温一直通入保护气；
(5)粗拔：将均匀化退火后的Φ4mm的铸态铜合金棒材拉拔成Φ2mm铜合金棒材，接着继续拉拔成直径为0.5mm的铜合金丝。
(6)热处理：将直径为0.5mm的铜合金丝进行退火处理；退火温度为550℃，退火时间为4小时，保护气氛为95％N2+5％H2。
(7)精拔：将经退火处理的铜合金丝精密拉拔成直径20μm铜合金单晶键合丝。
(8)热处理：将精拔后的铜合金键合丝进行退火处理；退火温度为500℃，退火时间为0.3秒，保护气氛为95％N2+5％H2，退火完成后，得到电子封装用铜合金键合丝。
(9)表面清洗：将退火处理后的电子封装用铜合金单晶键合丝先经稀释后的酸液中进行清洗，然后经超声波清洗，再经高纯水清洗、烘干。
(10)分卷：将成品微电子封装用铜合金单晶键合丝进行复绕、分卷、包装。
该铜合金单晶键合丝拉断力大于8cN(标准为>6cN，比标准提升30％以上)，延伸率大于15％(标准为6-12％，比标准提升25％以上)，最小熔断电流为0.29A(标准为0.24A，比标准提升20％以上)，且硬度适中，焊接成球性好，非常适用于高密度，多引脚集成电路封装。
实施例3
一种以高纯铜为主体材料的铜合金键合丝，组成该键合丝的材料由下列重量百分比的原材料组成：钨(W)含量为0.01％，银(Ag)含量为0.03％、钪(Sc)含量为0.02％、钛(Ti)含量为0.001％，铬(Cr)含量为0.01％、铁(Fe)含量为0.02％，且S和O在整个铜合金键合丝中的含量≤10wt.ppm，其余为铜和不可避免的杂质，之和等于100％；要求铜的纯度大于99.99％，钨、银、钪、铁、钛和铬的纯度都要大于99.999％。
微电子封装用铜合金单晶键合丝的制备工艺步骤和方法如下：
(1)提取高纯铜：将TU00铜(99.99％铜)作为阳极浸入电解液中，以高纯铜箔作为阴极浸入电解液中；在阳极、阴极之间输入7V、3.5A的直流电，以补充新鲜电解液方式维持电解液温度不超过60℃，待阴极积聚一定重量的纯度大于99.9999％的高纯铜时及时更换高纯铜箔，再经清洗、烘干备用。
(2)制备成铜合金铸锭：提取纯度大于99.9999％的高纯铜，高纯铜中杂质S和O含量小于5wt.ppm，然后加入钨、银、钪、铁、钛和铬；其成分含量按照重量百分比分别为：钨占0.01％，银占0.03％、钪占0.02％、钛占0.001％，铬占0.01％、铁占0.02％，其余为铜和不可避免的杂质，之和等于100％。这些金属经机械混合后放入高纯石墨坩埚中，在氩气保护条件下使用电弧炉加热使其熔化，进而制备成铜合金铸锭。
(3)连铸成铸态铜合金棒材：将制备好的铜合金铸锭加入有氮气保护的水平连铸金属连铸室，应用中频感应加热至1130℃，待完全熔化、精炼和除气后，将熔液注入连铸室中间的储液池保温，在维持3L/min净化氮气流量的连铸室中，完成对铜合金熔液的水平单晶连铸，得到Φ5mm的铸态铜合金棒材。
(4)均匀化退火：将Φ5mm的铸态铜合金棒材进行均匀化退火；退火温度为750℃，退火时间为10小时，保护气氛为95％N2+5％H2，冷却至室温一直通入保护气。
(5)粗拔：将均匀化退火后的Φ5mm的铸态铜合金棒材拉拔成Φ3mm铜合金棒材，接着 继续拉拔成直径为1mm的铜合金丝。
(6)热处理：将直径为1mm的铜合金丝进行退火处理；退火温度为500℃，退火时间为6小时，保护气氛为95％N2+5％H2。
(7)精拔：将经退火处理的铜合金丝精密拉拔成直径25μm铜合金单晶键合丝。
(8)热处理：将精拔后的铜合金键合丝进行退火处理；退火温度为450℃，退火时间为0.6秒，保护气氛为95％N2+5％H2，退火完成后，得到电子封装用铜合金键合丝。
(9)表面清洗：将退火处理后的电子封装用铜合金单晶键合丝先经稀释后的酸液中进行清洗，然后经超声波清洗，再经高纯水清洗、烘干。
(10)分卷：将成品微电子封装用铜合金单晶键合丝进行复绕、分卷、包装。
该铜合金单晶键合丝拉断力大于11.5cN(标准为>8cN，比标准提升30％以上)，延伸率大于18％(标准为8-16％，比标准提升12％以上)，最小熔断电流为0.3A(标准为0.26A，比标准提升7％以上)，且硬度适中，焊接成球性好，非常适用于高密度，多引脚集成电路封装。

Claims (10)

  1. 一种电子封装用高可靠性铜合金键合丝，其特征在于，其原料成分重量百分比组成为：铜含量为99.75％‐99.96％、钨含量为0.01‐0.1％、银含量为0.01％‐0.03％、钪含量为0.01％‐0.02％、钛含量为0.001％‐0.03％、铬含量为0.001％‐0.03％、铁含量为0.001％‐0.02％，不可避免的杂质，且杂质中S和O在整个铜合金键合丝中的含量≤10wt.ppm，全部元素含量之和等于100％。
  2. 根据权利要求1所述的电子封装用高可靠性铜合金键合丝，其特征在于，所述原料中铜的纯度大于99.99％。
  3. 根据权利要求1所述的电子封装用高可靠性铜合金键合丝，其特征在于，所述原料中要求钨、银、钪、铁、钛和铬任一种的纯度都大于99.999％。
  4. 权利要求1所述的电子封装用高可靠性铜合金键合丝的制备方法，其特征在于包括如下步骤：
    1)提取高纯铜：铜材料经电镀后，提取纯度大于99.9999％的高纯铜，再经清洗、烘干，备用；
    2)制备成铜合金铸锭：步骤1)所得高纯铜中加入钨、银、钪、铁、钛、铬，混合后在氩气保护条件下加热熔化，制备成铜合金铸锭；
    3)连铸成铸态铜合金棒材：将制备好的铜合金铸锭加入有氮气保护的金属水平连铸室，加热熔化、精炼和除气后，将熔液注入储液池保温，完成对铜合金熔液的水平连铸，得到Φ4‐Φ6mm的铸态铜合金棒材；
    4)均匀化退火：将Φ4‐Φ6mm的铸态铜合金棒材进行均匀化退火，控制退火温度为600‐900℃，退火时间为6‐10小时，保护气氛为95％N2+5％H2，冷却至室温过程一直通入保护气；
    5)粗拔：将均匀化退火后的Φ4‐Φ6mm铸态铜合金棒材拉拔成Φ2‐Φ3mm铜合金棒材，再拉拔成直径为0.5‐1mm的铜合金丝；
    6)热处理：将直径为0.5‐1mm的铜合金丝进行中间退火，退火温度为400‐600℃，退火时间为2‐6小时，保护气氛为95％N2+5％H2；
    7)精拔：对经热处理后的铜合金丝精密拉拔成直径分别为15μm‐50μm的成品铜合金键合丝；
    8)热处理：将精拔后的铜合金单晶键合丝进行退火，退火温度为400‐600℃，退火时间为0.2‐0.6秒，保护气氛为95％N2+5％H2；
    9)表面清洗，烘干，得成品铜合金键合丝。
  5. 根据权利要求4所述的电子封装用高可靠性铜合金键合丝的制备方法，其特征在于，步骤1)所述的高纯铜中杂质S和O含量小于5wt.ppm。
  6. 根据权利要求4所述的电子封装用高可靠性铜合金键合丝的制备方法，其特征在于，步骤2)所述的混合为机械混合。
  7. 根据权利要求4所述的电子封装用高可靠性铜合金键合丝的制备方法，其特征在于，步骤2)所述的加热熔化是高纯石墨坩埚中进行，加热熔化是使用电弧炉加热。
  8. 根据权利要求4所述的电子封装用高可靠性铜合金键合丝的制备方法，其特征在于，步骤3)所述的加热熔化是应用中频感应加热。
  9. 根据权利要求4所述的电子封装用高可靠性铜合金键合丝的制备方法，其特征在于，步骤9)所述的表面清洗先用稀释后的酸液对键合丝进行清洗，然后经超声波清洗，再经高纯水清洗。
  10. 根据权利要求4所述的电子封装用高可靠性铜合金键合丝的制备方法，其特征在于，步骤9)所述的表面清洗、烘干后还包括将成品铜合金键合丝进行复绕、分卷、包装。
PCT/CN2017/112638 2017-09-01 2017-11-23 一种电子封装用高可靠性铜合金键合丝及其制备方法 WO2019041587A1 (zh)

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Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109411438A (zh) * 2018-09-28 2019-03-01 汕头市骏码凯撒有限公司 一种铜合金线及其制造方法
CN110592421B (zh) * 2019-10-29 2020-07-07 吉林大学 铜合金、铜合金板材及其制备方法和应用
CN112687787B (zh) * 2020-12-29 2022-08-16 南昌航空大学 一种多晶串联led铜合金键合线的制造方法
CN114765081A (zh) * 2021-01-14 2022-07-19 日立金属株式会社 铜合金线、镀线、电线及电缆
CN114184841B (zh) * 2021-11-11 2023-11-24 中国电子科技集团公司第五十五研究所 一种封装外壳引线电阻的测量方法
CN114453452A (zh) * 2022-02-22 2022-05-10 温州中希电工合金有限公司 一种膨胀合金包铜复合线的制备方法
CN115255021B (zh) * 2022-09-29 2023-01-24 西安赛特思迈钛业有限公司 航空航天紧固件用大单重tc4钛盘圆丝材及其制备方法
CN117403050A (zh) * 2023-07-20 2024-01-16 贵研半导体材料(云南)有限公司 一种能够延缓脆化现象发生的封装用键合铜丝及制备方法
CN117137543B (zh) * 2023-11-01 2024-02-02 山东瑞安泰医疗技术有限公司 一种可降解封堵器及制备方法与应用

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6365036A (ja) * 1986-09-05 1988-03-23 Furukawa Electric Co Ltd:The 銅細線とその製造方法
JPH07138679A (ja) * 1994-05-09 1995-05-30 Toshiba Corp ボンディングワイヤー
CN105803252A (zh) * 2016-05-06 2016-07-27 河南优克电子材料有限公司 一种电子线缆用高强度高导电铜合金线的制造方法
CN105925831A (zh) * 2016-05-06 2016-09-07 河南理工大学 一种低弧度led封装用高强度银合金键合线的制造方法
CN105970016A (zh) * 2016-05-06 2016-09-28 河南理工大学 一种传输用高导电耐弯曲铜合金线及其制备方法
CN106992164A (zh) * 2017-04-10 2017-07-28 江西蓝微电子科技有限公司 一种微电子封装用铜合金单晶键合丝及其制备方法

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3896793B2 (ja) * 2001-02-16 2007-03-22 日立電線株式会社 高強度・高導電性銅合金材の製造方法
CN1254554C (zh) * 2002-11-15 2006-05-03 清华大学 高强度高导电稀土铜合金及其制造方法
AT7491U1 (de) * 2004-07-15 2005-04-25 Plansee Ag Werkstoff für leitbahnen aus kupferlegierung
KR20060090523A (ko) * 2005-02-07 2006-08-11 삼성전자주식회사 표시 장치용 배선 및 상기 배선을 포함하는 박막트랜지스터 표시판
CN102337461B (zh) * 2010-07-23 2013-10-16 宝山钢铁股份有限公司 一种高硬度马氏体不锈钢及其制造方法
US9476474B2 (en) * 2010-12-13 2016-10-25 Nippon Seisen Co., Ltd. Copper alloy wire and copper alloy spring
CN102644003A (zh) * 2011-02-16 2012-08-22 宋东升 高强度高导电耐腐蚀的稀土铜合金及其制造方法
SG190479A1 (en) * 2011-12-01 2013-06-28 Heraeus Materials Tech Gmbh Secondary alloyed 1n copper wire for bonding in microelectronics device
CN104060121B (zh) * 2014-06-05 2016-05-18 锐展(铜陵)科技有限公司 一种汽车用高耐磨铜合金线的制备方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6365036A (ja) * 1986-09-05 1988-03-23 Furukawa Electric Co Ltd:The 銅細線とその製造方法
JPH07138679A (ja) * 1994-05-09 1995-05-30 Toshiba Corp ボンディングワイヤー
CN105803252A (zh) * 2016-05-06 2016-07-27 河南优克电子材料有限公司 一种电子线缆用高强度高导电铜合金线的制造方法
CN105925831A (zh) * 2016-05-06 2016-09-07 河南理工大学 一种低弧度led封装用高强度银合金键合线的制造方法
CN105970016A (zh) * 2016-05-06 2016-09-28 河南理工大学 一种传输用高导电耐弯曲铜合金线及其制备方法
CN106992164A (zh) * 2017-04-10 2017-07-28 江西蓝微电子科技有限公司 一种微电子封装用铜合金单晶键合丝及其制备方法

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