PROJECT TITLE :

Highly Reliable and Manufacturable Ultrafine Pitch Cu–Cu Interconnections for Chip-Last Embedding With Chip-First Benefits

ABSTRACT:

Flip-chip packaging of Ultrafine pitch integrated circuits aggravates the strain–strain concerns as the interconnection pitch is decreased, requiring a basically totally different system approach to interconnections, underfill processes and interfaces, and therefore the substrate. This paper demonstrates an innovative and manufacturable answer to achieve excellent reliability at Ultrafine pitch $(simrm 30~murm m)$ using direct copper–copper (Cu–Cu) interconnections with adhesives. A number of 30-$murm m$ bump pitch check vehicles (TVs) were designed with 3 mm $times,$3 mm chips to extract each daisy chain resistance and single-bump resistance knowledge. Assembled bump resistivity was found to be $simrm 3hbox--4times$ below most solders. Performance of those TVs was studied for high temperature storage (HTS) life test, unbiased-highly accelerated stress check (U-HAST) and thermal cycling test (TCT). Test results showed that the assemblies with this next generation interconnection technology depicted excellent reliability results in HTS, U-HAST, and TCT tests. Based mostly on these results, it's concluded that adhesive materials, give distinctive opportunities for Ultrafine pitch and high performance interconnections.