High-Density Hybrid Substrate for Heterogeneous Integration

In this study, a high-density organic hybrid substrate for heterogeneous integration is investigated. Emphasis is placed on the design, materials, process, fabrication, characterization, and reliability of the hybrid substrate supporting three chips. The hybrid substrate consists of a fine metal linewidth and spacing redistribution-layer (RDL)-substrate, an interconnect-layer substrate, and a high-density interconnect (HDI) substrate. The heterogeneous integration of three chips on the hybrid substrate is characterized by continuity test and reliability assessed by reflow test and drop test. A nonlinear finite element analysis is performed to show the state of stress and strain at the conductive-paste-filled vias of the interconnect-layer substrate and critical solder joints under a thermal cycling condition.