STUDY ON EVALUATION METHOD OF RESIDUAL STRESS AND JOINT RELIABILITY OF SEMICONDUCTOR DEVICE BASED ON ULTLASONIC MEUREMENT TECHNOLOGY

本研究的目的是建立一种利用声显微镜测量的表面声波速度来评估半导体器件微连接的残余应力和可靠性的技术。首先，检查了通过表面声波速度评估树脂封装器件的应力的方法。接着，提出了测定作为半导体的阻挡金属的TiN薄膜的弹性模量的方法。最后，根据数值分析结果，对半导体器件微焊点的热应力特性和可靠性进行了分析。得到的主要结果如下：（1）高精度地测量了拉伸和压缩载荷下的声表面波速度。结果，计算出树脂材料的声弹性系数。此外，可以清楚地看出，具有应力分布的测试样本的应力可以被测量 ...更多信息 当然。并提出了利用声显微镜测量表面声波速度的残余应力评价方法。（2）在基体上沉积TiN薄膜的试样的声表面波速度取决于基体的声表面波速度。因此，表面声波速度只有薄膜不能被测量。因此，将实验结果整理成由弹性理论计算的简单方程，即可计算出薄膜的声表面波速度。此外，我们还提出了一种薄膜弹性模量的快速分析方法。(3)To阐明了热应力的性质，通过弹性理论和数值分析，考察了各种参数对热应力的影响。为进一步提高节点的稳定性提供了依据。此外，通过使用临界能量释放速率来计算粘合剂的剥离强度。从上述结果可以清楚地看出，当剥离长度较短时，接头稳定性得到保证。少

The purpose of this study is to establish the technique for the evaluation of the residual stress and the reliability of the microjoints of the semiconductor device by using the surface acoustic wave velocity measured by the acoustic microscope. First, the method of the stress evaluation of the resin packaged device by the surface acoustic wave velocity was examined. Next, we proposed the method of measuring the elastic modulus of the TiN thin film used as a barrier metal of the semiconductor. Finally, the characteristic on thermal stress and the reliability of the microjoints of the semiconductor device were examined based on the numerical analysis results. The main results obtained are as follows:(1)The surface acoustic wave velocity is measured in high accuracy under the tensile and the compressive load. As a result, the acoustoelasticity coefficient of the resin material was calculated. Moreover, it is clear that the stress of the test specimen with stress distribution could be mea … More sured. And, we proposed the residual stress evaluation method by the surface acoustic wave velocity measured by the acoustic microscope.(2)The surface acoustic wave velocity of the test specimen which deposits the TiN thin film on the substrate depends on the surface acoustic wave velocity of the substrate. Therefore, the surface acoustic wave velocity only of thin film cannot be measured. Therefore, the surface acoustic wave velocity only of thin film could be calculated by arranging the experimental result by the simple equation calculated from the elasticity theory. Moreover, we proposed the technique for reversely analyzing the elastic modulus of thin film.(3)To clarify the property of the thermal stress generated by mounting, the influence of various parameters on the thermal stress was examined by the elasticity theory and the numerical analysis. A basic knowledge to improve the joint stability further was obtained from the result of the above. Moreover, the peel strength of the adhesive was calculated by using a critical energy release rate. From result of the above, it become clear that the joint stability is secured when peel length is short. Less