Evaluation of Laser Releasable Temporary Bonding Adhesives for the Thinned Wafer Integration

Laser release technology is considered as a convenient method in advanced packaging applications, due to its high throughput, low stress, force-free during the release process. In this report, we evaluated two kinds of developed laser releasable temporary bonding adhesives to bond a device wafer onto a glass carrier. We demonstrated the coating uniformity, backgrinding, thermal stability, PECVD SiO
₂
deposition, high vacuum survivability, and PVD Ti/Cu deposition to investigate the performance of these temporary bonding adhesives for advanced packaging integration processes. Material B was failed to survive the thermal simulation test, emerging a gas pocket in the bond line. In contrast to Material B, the Material A presented completely excellent properties to satisfy all the simulation tests even under the high temperature and high vacuum conditions. Material A has successfully undergone laser ablation and cleaned with organic solvent without residues on the thinned wafer. Hence, Material A is recommended as a candidate for system-in-packaging (SiP), package-on-package (PoP), and heterogeneous integration applications.