Risk of CuxO phase penetration between the Ag plating layer and Cu during high-temperature reliability testing of interfaces bonded to cold sintered Ag nano-porous sheets on direct Ag-plated Cu substrates

초록

This study was carried out to understand the high-temperature stability of Ag nano-porous sheet bonded joints during thermal aging. The joints have been designed to be between two Ag metallization layers directly plated on copper layers of the die and substrate. The CuxO penetration between Ag plated layer and Cu substrate formed during thermal aging at 250 degrees C from 125 h, during which CuxO layer continuously grew up to 1000 h. The growing CuxO phase penetrated between the Ag plating and Cu, leading to voids that developed into a delamination layer over time. The delamination and continuous voids formed between CuxO layer and Cu had a critical effect on reducing the bonding strength. In this study, we thoroughly investigated the issues that may arise during thermal reliability testing at 250 degrees C when bonding commercial Ag nano-porous sheets directly Ag-plated onto Cu, from the perspective of microstructural development.

키워드