摘要FCBGA封装形式是一种比较先进的封装技术，它有许多的优点，例如可以有效提高芯片的利用效率，抗干扰能力强，散热效果优越等。随着科学技术水平的提高，越来越多的高科技产品涌现出来，由此推动电子器件的封装技术也需要得到进一步的提高。而焊点的失效将会导致封装的可靠性受到破坏，因此对于焊点的研究是研究封装技术的重中之重。因此本文将对FCBGA器件进行有限元模拟，并对其焊点进行重点分析。80316

本文采用ANSYS软件建立FCBGA封装模型，并在温度循环载荷的作用下，分析整体器件以及焊点的应力应变和蠕变变形，以此来判断其整体以及焊点的可靠性。

本文通过改变焊点的尺寸、数量、材料这三种方式，来对焊点的可靠性进行分析研究。其结果表明，无论改变焊点的尺寸、数量还是材料，其应力应变以及蠕变变化的最大值都发生在拐角处的焊点与芯片的焊接面上，这就说明拐角处的焊点对于器件整体的可靠性发挥着至关重要的作用。

该论文有图42幅，表5个，参考文献31篇。

毕业论文关键词：FCBGA封装结构  有限元法  可靠性

Optimization design and reliability of lead free solder joints for FCBGA devices

Abstract FCBGA package is a kind of advanced packaging technology and it has many advantages。 For example, it can effectively improve the efficiency of the use of the chip, the ability to resist interference, heat dissipation and so on。 With the improvement of the level of science and technology, more and more high-tech products have emerged, which promote the packaging technology of electronic devices also need to be further improved。 The failure of solder joint will lead to the reliability of the package to be damaged, so the research of the solder joint is the most important content of packaging technology。 Therefore, this paper will carry on the finite element simulation of FCBGA devices, and focus on the analysis of the solder joints。

In this paper, the ANSYS software is used to build the FCBGA package model, under the action of temperature cyclic loading, the stress and strain of the whole device and the creep deformation of the solder joint are analyzed, in order to judge the reliability of the whole and the solder joint。

In this paper, the reliability of solder joints is studied by changing the size, quantity and material of the solder joints in three ways,。The results show that the maximum value of the stress and strain as well as the maximum value of creep changes occur at the corner of the solder joint and the welding surface of the chip, regardless of the size, the number or the material of the solder joints, this shows that the solder joint which at the corner plays a vital role in the reliability of the overall device。

This paper has 42 figures, 5 tables and 31 references。

Key Words: FCBGA package structure  Finite element method  Reliability

目录

摘要Ⅰ

AbstractⅡ

目录Ⅲ

图清单V

表清单VI

1 绪论1

1。1引言1

1。2集成电路技术的发展与表面组装技术2

1。3 FCBGA封装技术5

1。4国内外发展现状5

1。5本文研究内容6

1。6本文研究的意义6

1。7本章小结7

2 有限元模拟分析方法8

2。1有限元模拟分析方法简介8

2。2 对ANSYS软件的介绍8

2。3 ANSYS典型的分析过程9

2。4本章小结10

3 FCBGA封装结构的有限元模拟11

3。1 FCBGA有限元模型的建立11

3。2模型的参数选择13

3。3载荷的施加13

3。4模拟计算结果以及对其的分析处理14

3。5本章小结25