Vacuum underfill technology for advanced packaging

We developed vacuum assisted underfill 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 such an advanced package. It was also confirmed that the newly developed underfill materials have good reliability on the large die package. © 2011 IEEE.