Shelf-Life Evaluation of Lead-Free Component Finishes
The integrated circuit (IC) industry is converting to lead (Pb)-free termination finishes for leadframe-based packages. IC component users need to know the maximum length of time that components can be stored prior to being soldered. This study predicts shelf life of the primary Pb-free finishes being proposed by the industry. Components were exposed to a controlled environment, with known aging acceleration factors. The Pb-free components were exposed to a Battelle Class 2 environment both in and outside of their normal packing materials. Results show that the Pb-free-finished ICs stored in tubes, trays, or tape-and-reel packing material pass solderability testing after 96-h exposure to the Class 2 environment. This exposure correlates to eight years in an uncontrolled indoor environment, such as a warehouse.