Component Reliability After Long Term Storage

Each year the semiconductor industry routes a significant volume of devices to recycling sites for no reliability or quality rationale beyond the fact that those devices were stored on a warehouse shelf for two years. This study identifies the key risks attributed to extended storage of devices in uncontrolled indoor environments and the risk mitigation required to permit safe shelf-life extension. Component reliability was evaluated after extended storage to assure component solderability, MSL stability and die surface integrity. Packing materials were evaluated for customer use parameters as well as structural integrity and ESD properties. Results show that current packaging material (mold compound and leadframe) is sufficiently robust to protect the active integrated circuits for many decades and permit standard reflow solder assembly beyond 15 years. Standard packing materials (bags, desiccant, and humidity cards) are robust for a 32 month storage period that can be extended by repacking with fresh materials. Packing materials designed for long term storage are effective for more than five years....