Chip-to-Wafer Hybrid Bonding for high performance 2.5D applications

Abstract

Chip to wafer hybrid bonding is the prefer choice for high performance 2.5D application as it offered very high dense I/O population down to 10¼m pitch with 5¼m pad diameter. This type of pitch and pad diameter cannot be obtained with conventional copper bump with solder cap. The conventional copper bump with solder cap had issue with solder merging, void and cracked solder. We had demonstrated good Cu-Cu interface with 10¼m pitch with 5¼m Cu pad diameter.