Chip Underfill

As microelectronic packaging technology continues to evolve toward higher integration and ultra-thin designs, advanced interconnection processes such as Flip Chip and Chip Scale Packaging (CSP) have become mainstream. However, the inherent coefficient of thermal expansion (CTE) mismatch between silicon chips and organic substrates causes interconnect solder balls to endure long-term alternating thermo-mechanical stresses during service, which easily leads to the initiation and propagation of fatigue cracks. Meanwhile, drop impacts and bending deformations experienced by portable devices also pose severe threats to the structural integrity of solder joints. To address these reliability challenges, Underfill technology has emerged.