Reliability of μPILR Packages under Shock Loading

摘要

Portable consumer electronics is a critical market segment for modern electronics devices which includes lightweight systems such as cell phone, laptop computer, PDA, etc. Due to an ever increasing demand for integration of higher functionality, miniaturization is a parallel ongoing trend for design of microelectronics packages used in such devices. One of the resulting challenges is maintaining or improving reliability of second level interconnects for these packages with respect to mechanical and thermomechanical loading. Board-level drop or impact response of a surface mounted package assembly is an increasingly important facet of the reliability evaluation for application in hand-held or mobile electronics for obvious reasons. Rupture of L2 interconnects (solder joints) and test board pad/trace failures are the most commonly observed modes of failure due to shock loading conditions. Various design and test parameters such as materials, geometry and loading configuration affect the failure mechanism involved. This paper presents JEDEC standard JESD22-B111 compliant drop testing results for a new interconnect platform- a novel design using miniature copper contacts (μPILR). An independent numerical (Explicit Dynamic Finite Element Analysis) study is performed to examine μPILR design as well as comparable BGA (Ball Grid Array) design for their response to shock loading conditions at level 2 (L2) interconnects. The μPILR design is intended for higher adaptability to increasing I/O density and improvised test/burn-in capabilities. Drop testing is performed according to JEDEC board level shock testing standard JESD22-B111 for 0.4 mm, 0.5 mm, 0.65 mm pitch μPILR test vehicles. Finite Element Analysis was conducted to study 0.5 mm pitch μPILR and BGA designs.