Vacuum underfill technology for advanced packaging (IMPACT 2011)

We developed vacuum underfill (VCUF) technology for large die (>;18 × 18 mm) with fine pitch area array bumps (<; 150 μm pitch) to solve a critical underfill void issue. Material development and process optimization are the keys to realize a stable process for future package. It was also confirmed that the newly developed underfill materials have good reliability on the large die package with vacuum assisted underfill process.