Design and Fabrication of WLP Compatible Miniaturized Pressure Sensor System with Through Silicon Via (TSV) Interconnects

In this paper, a Wafer Level Packaging (WLP) compatible pressure sensor system enabled with Through Silicon Via (TSV) and Au-Sn inter-chip micro-bump bonding is designed and fabricated in lab, in which TSV transmits electrical signal from piezoresistive circuit to processing circuit vertically.

The pressure sensor system includes TSV integrated piezoresistive pressure sensor chip and Read-Out Integrated Chip (ROIC) in which TSV also incorporated. Two CMOS compatible fabrication process flows for pressure sensor system are demonstrated. And, flip chip bonding structure of TSV integrated pressure sensor with a ROIC are realized using one of these two process flows. Inter-chip interconnects enabled with TSV and micro-bump bonding is obtained.