An Improvement of Plasma Cleaning Time towards Leadframe Oxidation Performance

Abstract

Package delamination causing the tendency to absorb humidity which lead to device failure towards Integrated Circuit (IC) packaging[1]. Most of the screened unit being analyzed and results showed failure due to popcorn effect. Popcorn effect caused by moisture penetration effecting the packaging to expend causing delamination and cracking during high temperature application. In this paper, delamination had been filtered from Scanning Acoustic Microscope (SAM) towards the failure units and once package encapsulation had been done the root cause being identified as leadframe oxidation problem. The leadframe oxidation can be easily observed during wire bonding and oven curing process since it involved with high temperature process which the indication showed leadframe discolouration appearance. The aim of this work is to evaluate plasma parameter to achieve delamination free product by assessing the plasma cleaning time. Additional plasma cleaning before molding process had been identified as a solution towards free leadframe oxidation process which leads to zero delamination issue for package that using Copper leadframe. Higher plasma cleaning time produced significantly lower leadframe oxidation issue however the Unit Per Hour (UPH) will be effected.