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

本文对微连接中高精度定位和过程控制的视觉系统进行了研究。以下是结果。1)采用分离视野的成像方法实现高精度视觉感知。本研究提出了一种分离滤波方法，利用带棱镜的电视摄像机对不同的两个区域进行成像，实现了高精度的视觉感知。2)利用灰度方差对微关节进行模式匹配。我们关注了表示局部区域灰度分布的方差值，明确了由该方差值匹配的模式对于表面粗糙度或观看条件引起的亮度变化是最有效的。3)基于区分阈值法的微关节自动检测。提出了一种基于统计方法和发生概率分布的微关节图像阈值选择方法，并阐明了当亮度变化引起微关节场自动提取时，采用该方法可获得相同的结果是最有效的。4)通过控制单点压片加载轮廓，实现低温小变形粘接。单点贴片技术中的热声键合过程主要是由金包和贴片引线之间界面的塑性流动所主导的。在初始接触过程中，存在最小的加载力来获得接触，另一方面，在后一粘附过程中，在较低的加载力下，超声能量进入界面的贡献变大。

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.