Abstract
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摘 要
摘 要
在当今21世纪，半导体产业蓬勃发展，半导体IC和半导体器件已经在各行各业广为使用，从卫星通信、军事产品、信息工业至普通家用产品、小家电，同时伴随着半导体产业和器件的发展，人们的生活愈来愈便捷和智能。
半导体产业在发展的过程中，分工逐渐精细，而半导体封装产业也成为了一个在半导体产品中占据较大比例的产业，如何能够提高半导体封装的效率和性能，降低成本，就摆在了所有半导体产业人员面前。随着产品的I/O口变多，半导体封装中的键合成本也占据着较大比例，在键合中采取新的材料，新的工艺，在保证产品性能和可靠性的前提下，降低材料成本，是产业发展的一个趋势。
随着设备技术的发展，采用铜丝代替原来的金丝作为焊丝，已经成为了可能。由于金和铜的材料价格存在着较大差异，很多公司和研究人员投入了很大精力，进行各方面的尝试，经过多年的研究，长电科技已经在这方面取得了较大的突破。
本文主要研究用铜丝代替传统的金丝材料，采用新的技术和工艺参数，运用DOE试验法，找到了最佳的铜线球焊的工艺参数（主要是球焊功率、球焊压力、球焊时间）窗口，加上设备的改进（原有将焊线高温熔化时加上氢气和氮气保护装置），并将做出来的成品与原来的产品进行性能和可靠性的比较，发现铜线球焊产品的主要电性能参数与原来金线产品的参数分布一致，可靠性能还能避免原有的金铝合金的脆化现象，推进了半导体封装产业和半导体器件的不断发展。
关键词 球焊；焊接工艺；封装；铜线球焊；可靠性
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Abstract
Abstract
In twenty-first Century, the semiconductor industry with development, IC and semiconductor device has been widely used in all walks of life to carry out, from the satellite communications, military products, information technology industry and ordinary household
products,
small
household
electrical
appliances, accompanied
by
the development of the semiconductor industry and devices, people's life more and more convenient and intelligent.
The
semiconductor
industry in
the
development
process,
gradually fine division, and semiconductor packaging industry has also become a occupy a larger proportion of semiconductor products in the industry, how to improve the efficiency and performance, semiconductor packaging cost reduction, is placed in front of all
of
our
semiconductor industry personnel. Along
with
the
product
I/O
port number, bonding the semiconductor package also occupy a great proportion, adopt new materials in the bonding process, new technology, in order to ensure the product performance and reliability, reduce the cost of the materials, is an industry trend. Instead of the original with gold as the wire, the wire material and technology, with the development of equipment and technology, has become possible, since there are large differences between gold and copper material prices, many companies and researchers have devoted great respect.
This paper mainly studies the copper wire instead of the traditional gold wire material, the technology and the new process parameters, plus improvement of equipment performance and reliability, compared to do out of the finished product and the original product, promote the continuous development of semiconductor device and semiconductor packaging industry.
Keywords
energy, trying various aspects, after years of research, with
the experience accumulation, JCET technology has made a great breakthrough in this
wire bonding; bonding
technology; packaging; copper ball
bonding, reliability;
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目 录
目录
摘 要 .................................................................................................................................... I Abstract .................................................................................................................................. II 第一章 绪论 ........................................................................................................................... 1
1.1 引言 .......................................................................................................................... 1 1.2 国内外研究现状、发展动态 .................................................................................. 1 1.3 本文的内容安排 ...................................................................................................... 3 第二章 半导体封装中引线键合的基本原理 ....................................................................... 4
2.1 引言 .......................................................................................................................... 4 2.2 半导体封装介绍 ...................................................................................................... 5
2.3 键合工艺的特点 .................................................................................................................. 5 2.4 超声波球焊的原理 .............................................................................................................. 6 2.5 超声波球焊的过程 .............................................................................................................. 7 2.5.1 初始位置 .......................................................................................................................... 8 2.5.2 第一焊接检查 .................................................................................................................. 9 2.5.3 第一焊接 .......................................................................................................................... 9 2.5.4 拉线位置 .......................................................................................................................... 9 2.5.5 第二焊接瞄准 .................................................................................................................. 9 2.5.6 第二焊接检查位置 .......................................................................................................... 9 2.5.7 第二焊接 .......................................................................................................................... 9 2.5.8 扯丝 .................................................................................................................................. 9 2.5.9 成球位置 ........................................................................................................................ 10 2.6 本章小结 ................................................................................................................ 10 第三章 超声波球焊设备的结构和作用 ...................................................................... 11 3.1 引言 ........................................................................................................................ 11 3.2 KS公司球焊机介绍 ............................................................................................... 11 第四章 铜线超声球焊工艺的几个重要因素 .............................................................. 14 4.1 引言 ........................................................................................................................ 14 4.2 铜线超声球焊的劈刀 ............................................................................................ 14 4.3 键合的工艺参数 .................................................................................................... 15
4.3.1 键合超声能量 ................................................................................................................ 15 4.3.2 键合压力温度时间 ............................................................................................ 16 4.4 铜线 ........................................................................................................................ 16 4.5 焊盘 ........................................................................................................................ 17 4.6 本章总结 ................................................................................................................ 17 第五章 铜线工艺设备和参数的优化调整 ......................................................................... 18
5.1 引言 ........................................................................................................................ 18 5.2 铜线焊接工艺要求 ................................................................................................ 18
5.2.1 焊接位置 ........................................................................................................................ 18 5.2.2 焊点状况 ........................................................................................................................ 18 5.2.3 弧度要求 ........................................................................................................................ 18 5.2.4 焊线要求 ........................................................................................................................ 18 5.2.5 芯片外观 ........................................................................................................................ 19 5.2.6 键合强度 ........................................................................................................................ 19
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江苏科技大学工程硕士学位论文
5.3 铜线材料的性能 .................................................................................................... 19
5.3.1 铜线的力学性能 ............................................................................................................ 19 5.3.2 铜线的电性能 ................................................................................................................ 20 5.3.3 铜线的热学性能 ............................................................................................................ 20 5.3.4 铜线优势 ........................................................................................................................ 21 5.4 试验材料及方法 .................................................................................................... 21
5.4.1 球焊机设备与改进 ........................................................................................................ 21 5.4.2 用DOE试验法对铜线球焊参数进行改进 .................................................................... 22 5.5 试验结果与分析 .................................................................................................... 30
5.5.1 剪切力与拉力 ................................................................................................................ 30 5.5.2 弧度 ................................................................................................................................ 31 5.5.3 可靠性 ............................................................................................................................ 31 5.5.4 不良品 ............................................................................................................................ 31 5.5.5 金铜丝球焊焊点金属间化合物生长 ............................................................................ 31 5.5.6 金铜丝球焊焊点剪切断裂载荷和失效模式 ................................................................ 32 5.5.7 金铜丝球焊拉伸断裂载荷和失效模式 ........................................................................ 32 5.5.8 铜丝球焊产品的电性能 ................................................................................................ 33 5.6 铜丝球焊产品的电性能可靠性 ............................................................................. 33 5.7 结论 ......................................................................................................................... 34 5.8 本章小结 ................................................................................................................ 34 总结与展望 ........................................................................................................................... 35 参考文献 ............................................................................................................................... 36 致 谢 ................................................................................................................................... 38
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