Thin Small Leadless Package's (TSLP): Adhesion Failure Analysis After Electroless Nickel Immersion Gold (ENIG) Process

Electroless Nickel Immersion Gold (ENIG) plating could offer superior durability and high corrosion resistance as well as providing excellent solderability. However, in plating chemistry field, poor intermetallic between 2 metals will lead to adhesion failure, and which would impact customer mounting application or even field failures. The main challenges to achieved robust manufacturing process is to understand adhesion failure mode between Nickel (Ni bump) to Nickel Phosphorous (Ni-P), based on several factors. A fundamental aspect underlying the coating process can be defined in bath technique, parameter and pre-process preparation. In this study, author investigating on previous series of improvement actions in adhesion failure. Based on lesson learn, all implemented action done with assumption that individual quality indices are independent to each other. But in real practise, the assumption may not be valid always. A Series of Block RSM were performed to verified current control in TSxP Galvanic Manufacturing line. Introduction of outlier parameter in the DOE is to increase the experiment window, and adhesion test act as output response (C=0). Then, developed mathematical model from RSM regression were used to validated and analysed the develop model with current production window (loading factor). From RSM analysis, “ZERO” adhesion failure event can be achieved via optimization of current production window (loading factor).