Within-Wafer and Within-Die Uniformity of Bond Strength for Hybrid Bonding

Hybrid bonding is a promising vertical interconnection method for advanced 3D/chiplet integration. However, there are still some issues to be solved before it can be implemented into mass production with robust process integration. One of these is to establish a method for measuring bond strength precisely. Double-cantilever-beam test is the most frequently used method for measuring bond strength for hybrid bonding, however, it can only evaluate the edge/bevel region. In addition, it is inapplicable to D2W bonding without making a notch in chip side. In this study, we propose Nanoindentation (NI) test as alternatives to DCB measurement, which can measure the bond strength of the entire region of the wafer without special sample preparation at the bonding step. In this paper, we demonstrated the uniformity measurement within-wafer and within-die originated from W2W and D2W bonded samples using NI test.