Study on Vision System for High Accurate Positioning and Process Control in Micro-Joining

在这项研究中，讨论了微连接中高精度定位和过程控制的视觉系统。结果如下：1）通过分离视野的成像方法实现高精度视觉传感。本研究提出的分离观察方法可以通过带有棱镜的电视摄像机拍摄不同的两个区域的图像，从而实现高精度视觉传感。2）使用灰度方差的微接头图案匹配。我们关注表示局部区域灰度分布的方差值，并阐明通过该方差值进行的图案匹配对于引起的亮度变化是最有效的3）采用区分阈值法自动检测微接头。提出了一种基于统计方法和发生概率分布的微接头图像阈值选择方法，并阐明了当亮度变化时，采用该方法自动提取微接头场可以获得相同的结果。4）单点TAB中通过控制加载曲线进行低温小变形粘合。单点TAB技术中采用的热超声粘合工艺占主导地位。由金凸块和 TAB 引线之间界面处的塑性流动引起。在初始接触过程中，存在最小的加载力以获得接触，而另一方面，在后期的粘合过程中，在较低的加载力下，超声能量对界面的贡献变大。

In tis study, the vision system for high accurate positioning and process control in the micro joining are discussed. The followings are results.1) High accurate visual sensing by imaging method with separated fields of vision.An separative wiewing method that is proposed in this research enables to take a image for the different two regions by a TV camera with a prism and makes possible a high accurate visual sensing.2) Pattern matching of micro joints using variance of gray level.We paid attention to the variance value which presents the distribution of gray level in a local region and clarified that the pattern matching by this variance value is the most effective for the change of the brightness caused by the surface roughness or the viewing condition.3) Automatic detection of micro joints by distinguished thresholding method.We proposed a new threshold selection method of the micro-joints images based on the statistical method and occurred probability distribution, and clarified that it is most effective that the automated extraction of micro-joint fields can be obtained the same result by this method when the change of the brightness caused.4) Low temperature and small deformation bonding by control of loading profile in single point TAB.The thermosonic bonding process used in the single point TAB technology is dominated by the plastic flow at the interface between a gold bump and TAB lead. In the initial contact process, the minimum loading force exists to obtain the contact, and the other hands, in the latter adhesion process, the contribution of the ultrasonic energy into the interface becomes larger under the lower loading force.