An experimental study of popcorning in plastic encapsulated microcircuits

A potential reliability problem in plastic encapsulated microcircuits is moisture-induced popcorning, which can arise during the reflow process. This article describes an experimental setup that is used to rapidly assess the moisture sensitivity of plastic encapsulated microcircuits and classify them based on The Institute for Interconnecting and Packaging Electronics Circuits (TPC) and Joint Electron Device Engineering Council (JEDEC) guidelines. Experimental results are then presented which show that only one of the three reflow cycles specified as part of the current guidelines is necessary. The study then presents the role played by the die and die attach material in popcorning, Finally, this study suggests an alternate technique to deter popcorning-the use of optimum temperature ramp rates in board assembly