Development of high throughput adhesive bonding scheme by wafer-level underfill for 3D die-to-interposer stacking with 30µm-pitch micro interconnections

In 3D integration, die stacking together with underfilling by capillary-type underfill are the principal processes within whole conventional assembly process. How to integrate and shorten the total process steps during assembly and increase the die-stacking yield especially for thin die stack to improve the throughput that can meet the requirement from industry will be a crucial issue. In this investigation, we proposed the high throughput adhesive bonding scheme by using wafer-level underfill material for the die-to-interposer stacking with 30µm-pitch micro interconnections. The reliability characterization of the die-to-interposer stack by such bonding scheme was implemented and confirmed.