Electrical components can fail during their function in an electrical circuit, especially in a harsh environment. One of the possible failure reasons is the electrochemical migration, which leads to a short circuit or change of electrical parameters of components. This paper focuses on electrochemical effects and explains mechanisms leading to the formation of a conductive path within a component molded in a plastic package. Appropriate diagnostic methods - SEM/EDS and penetration tests have been chosen in order to find the root cause for short circuit creation. It was found that the conductive path appeared due to electrochemical migration of silver between the Electrically Conductive Adhesive (ECA) joints connecting the capacitor package. A tiny gap that was found between the molding compound and the leadframe of the package, showed to be the necessary condition for the electrochemical migration to appear. The main aim of this work was not just to identify the cause of an inadvertent conductive path creation, but also to identify the part of the manufacturing process, where similar problems can be prevented.

电气组件在电路中运行期间可能会发生故障，尤其是在恶劣的环境中。可能的故障原因之一是电化学迁移，这会导致短路或组件电气参数的变化。本文着重于电化学效应，并解释了导致在塑料封装中模制的部件内形成导电路径的机理。适当的诊断方法-已选择SEM / EDS和渗透测试，以找出造成短路的根本原因。发现导电路径的出现是由于银在连接电容器组的导电胶（ECA）接头之间的电化学迁移。在模塑料和封装的引线框架之间发现了一个很小的间隙，表明这是发生电化学迁移的必要条件。这项工作的主要目的不仅是要确定造成无意的导电路径的原因，而且还要确定制造过程中可以避免类似问题的部分。