Sun Yameng, Ma Kun, Song Yifan, Zi Tongtong, Liu Xun, Feng Zheng, Zhou Yang, Liu Sheng
Laboratory for Electronic Manufacturing and Packaging Integration, The Institute of Technological Sciences, Wuhan University, Wuhan 430070, China.
School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430070, China.
Micromachines (Basel). 2023 Aug 30;14(9):1695. doi: 10.3390/mi14091695.
There is an increasing demand for the use of automotive sensors where complex working environments may easily lead to failure. Wire pull and shear test models based on finite-element analysis are established to evaluate their reliability by investigating the failure mode and mechanism of gold wire bonding. The effect of shear force position and pull force position on failure is also analyzed. The bonding failure was verified by experiments, which is consistent with the simulation result. The results show that: (1) The three-dimensional quantitative modeling reveals the process of bonding delamination and stress concentration. (2) The bonding-slip method (BSM) is adopted in the gold ball detaching process. The concept of three states, including deformation accumulation, cracking, and disengagement, was put forward to reveal the interface stress evolution trend according to the shear testing results. The results indicate that in the interface, the stress in the deformation accumulation state decreases from the tensile side (or compression side) to the center, and the stress in the cracking and disengagement states reduces gradually from the tensile side to the edge. When the interface is completely separated, the failed shear force concentrates on 42 g. The concept and theory proposed in this work can effectively reveal the failure mechanism of bonding interface and help to establish a new failure criterion.
在复杂工作环境中，汽车传感器的使用需求日益增长，而这种环境可能容易导致传感器失效。基于有限元分析建立了引线拉力和剪切力测试模型，通过研究金线键合的失效模式和机理来评估其可靠性。还分析了剪切力位置和拉力位置对失效的影响。通过实验验证了键合失效，实验结果与模拟结果一致。结果表明：(1)三维定量建模揭示了键合分层和应力集中的过程。(2)在金球分离过程中采用了键合滑移法(BSM)。根据剪切测试结果，提出了包括变形累积、开裂和脱离在内的三种状态的概念，以揭示界面应力演变趋势。结果表明，在界面中，变形累积状态下的应力从拉伸侧(或压缩侧)向中心减小，开裂和脱离状态下的应力从拉伸侧向边缘逐渐减小。当界面完全分离时，失效剪切力集中在42 g。本文提出的概念和理论能够有效揭示键合界面的失效机理，并有助于建立新的失效准则。
