| Popis: |
Pre-plated leadframe (PPF) is usually plated with nickel-palladium plating, and the hardness of the plating is much higher than tin (Sn) plating. However, in some cases, it is observed that the PPF is more prone to damage that resulted in exposed copper (Cu). The damage is induced by mechanical contact of the test pin with external lead of integrated circuit (IC) package. Currently, at Sn and PPF plating processes, quality checks such as plating layer hardness, thickness, grain size, surface roughness, and etc. were carried out. There is no measurement method that characterizes the damage resistance of a particular plating layer. This work studies the application of scratch test as a damage test method to characterize the in leadframe plating surface of both Sn and PPF, in relation with various types of diamond indenter and scratch techniques which is progressive load scratch and constant load scratch test. Recommendation is given at the end of this paper. |
