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毕业论文-纳米Ag+Cu混合焊膏制备及其低温烧结连接用于电子封装，共91页，45485字
中文摘要
为保护环境和防止铅对人体的伤害，电子工业无铅化越来越显得重要；同时，
随着芯片集成度越来越高，发热量上升，互连材料在低温下焊接高温下稳定服役
的性能也成为电子工业中的一个挑战。纳米颗粒的小尺寸效应带来的高表面活性，
有利于其在低温下烧结致密。因 Ag、Cu 具有良好的导电、导热和力学性能，其纳
米颗粒膏有望作为理想无铅互连材料。本文中，在用液相化学还原法分别制备纳
米 Ag（约 40nm）、纳 米 Cu（约 100nm）颗粒膏后，机械混合制得 Ag 与 Cu 配比
不同的（Ag+Cu）纳米混合膏，并对各种焊膏进行了烧结性能及其低温烧结连接
Cu 箔与 Cu 丝的试验研究，测试了接头的拉剪性能并分析断裂方式。结果表明，
纳米 Cu 中适量添加纳米 Ag 颗粒可改善烧结性和连接性；提高烧结连接温度和压
力、延长保温时间有利于高强度接头的形成；针对搭接长度为 4.5mm 的 Cu 箔与
Cu 丝接头，连接温度高于 180℃、保温时间长于 30min、连接压力约 400N 时均可
获得断裂发生在母材 Cu 中的高强度接头。接头拉剪断裂方式包括：断裂在母材
Cu 丝中；断裂在烧结层中；断裂在 Cu 与烧结层的结合界面上；断裂时部分发生
在烧结层中，部分发生在结合界面。
关键词：纳米焊膏；低温烧结连接；拉剪断裂力

ABSTRACT
In order to avoid the environment pollution and the human body's injury led by the
element Pb and its compounds, lead-free requirement in electronics industry is
increasingly imperious. At the same time, higher heat generation from chips would be
accompanied with the high chip integration. In this case, it becomes a challenge for the
interconnected materials, which are bonded at low temperature, to then serve stably at
high temperature. As well known, the huge surface energies due to the small size effect
of nano particles are beneficial to their sintering compaction at low temperature. The
Nano Ag and nano Cu particles are hoped to be the ideal lead-free interconnection
materials because of their metal properties, such as high mechanical properties, and
good electrical and thermal conductivity. In this paper, nano Ag paste with a particle
diameter of about 40nm and nano Cu paste with a particle diameter of about 100nm
were prepared by using the liquid phase chemical reducing process, respectively. The
nano metal particle composite pastes with a various mol rate of nano Cu to nano Ag
were mechanically made up by mixing the mentioned Ag paste and Cu paste. In
succession, the sinterting properties of the (Ag+Cu) composite paste and the low
temperature sintering bonding of Cu foil to Cu fine wire were carried out, which is
accompanied with the joints’ property test and fracture mode analysis. The results
showed that the addition of nano-Ag particles can improve the sintering ability and
bonding ability of nano-Cu paste. Also, the higher sintering bonding temperature and
pressure and the longer sintering time can help the formation of the strong joints. For
the joints of the copper foil to wire with an overlapping of 4.5mm under the bonding
conditions of sintering temperature higher than 180℃, pressing load of about 400N and
holding time longher than 30min, the fracture would occur in the copper wire base
metal, which indicated that robust bonding was achieved. The joints’ fracture
modes/positions contain: 1) in the copper wire base metal, 2) in the sintered bonding
layer, 3) at the bonding interface; 4) both of in the sintered bonding layer and the
bonding interface.
Key words: Nano particle paste; low temperature sintering bonding; tensile shear
fracture force

目录
中文摘要 ..III
ABSTRACT..IV
第 1 章
引言.1
1.1 研究背景 ..... 1
1.1.1 电子封装无铅化要求 ..... 1
1.1.2 传统铅锡焊料的特点 ..... 4
1.1.3 无铅互连材料的要求 ..... 4
1.1.4 课题研究的目的和意义 ... 5
1.2 无铅互连材料的研究现状 ....... 5
1.2.1 低温无铅钎料的研究现状 . 5
1.2.2 高温无铅钎料研究现状 ... 7
1.2.3 微/纳米金属颗粒膏 ...... 8
1.2.4 纳米Ag和Cu颗粒的制备方法 ...... 15
1.3 本文的主要研究内容 .. 16
第 2 章 试验材料、设备与方法18
2.1 纳米颗粒制备用试剂与设备 .... 18
2.2 纳米金属颗粒制备原理 19
2.3 母材及其接头制备方法和性能测试 ...... 20
2.4 差热分析和显微分析仪器 ...... 23
第 3 章 纳米Ag、Cu及其混合焊膏的制备与低温烧结性能..25
3.1 纳米Ag膏多元醇法制备 25
3.2 纳米Cu膏的制备 ...... 26
3.3 Cu+Ag混合纳米焊膏的制备 ..... 27
3.4 TG/DSC热特性分析 .... 28
3.5 纳米焊膏的烧结性能 .. 29
3.6 烧结后的XRD分析 ..... 32
3.7 小结 32
第 4 章 纳米焊膏低温烧结连接Cu箔与Cu丝研究 34
4.1 纳米焊膏烧结连接铜箔和铜丝前的准备和接头制备 34
4.2 连接温度和Cu与Ag配比对接头拉剪断裂力及断裂方式的影响 34
4.3 连接压力和Cu与Ag配比对接头拉剪断裂力和断裂方式的影响 41
4.4 保温时间和Cu与Ag配比对接头拉剪断裂力和断裂方式的影响 44
4.5 接头低温烧结连接形成及其拉剪断裂模式的分析探讨 ...... 48
4.6 对课题深入研究的建议 51
4.7 本章小结 .... 51
第 5 章
结论53
插图索引 ...54
表格索引 ...57
参考文献 ...58
致谢
声明
附录A 书面翻译 ......63