改善封装产品冲切毛刺的探讨

Study for Improving Cutting Burrs Problem of IC Packaging

切筋、成形是集成电路封装的重要工序之一。切筋、成形过程产生的毛刺,不仅影响到外观质量,而且会影响到产品的电性能、安全和可靠性。文章首先叙述了切筋、成形过程产生的几种形态的毛刺,接着从模具结构特点讲述了产生这些毛刺的原因。然后针对产生的原因,提出了几种改善措施。重点对模具的改善、易损件的控制和框架设计制造及框架材料的选择等问题阐述了自己的见解。要改善和消除封装产品冲切、成形过程产生毛刺的现象,对模具结构、刀具形状及精度和框架材料提出了较高的要求。最后,建议了几种新的去毛刺工艺,希望起到抛砖引玉的作用。

Trimming ＆ Forming process is one of the important processes of IC packaging. During this process, cutting burrs have bad effect on product＇ s visual quality, as well as the electrical properties, safety and reliability. In this paper, it first introduces several kinds of burrs generated during trimming ＆ forming process. Then, reasons that the burrs can exist are analyzed in terms of tooling configuration characteristics. After that, we propose several corrective measures based on these reasons. The measures here put emphasis on improving tooling, control of the wearing parts, lead frame design and manufacturing and the way to select the material of lead frame. Finally it is concluded that we must have more demanding requirements on the tooling configuration, cutting tool＇ s shape and precision, and the material of lead frame to improve the trimming ＆ forming process and eliminate the cutting burrs. In addition, several new deburring techniques are proposed in the paper.