A Package Demonstration with Solder Free Compliant Flexible Interconnects.

I. Shubin*, A. Chow, J. Cunningham, M. Giere, N. Nettleton, N. Pinckney, J. Shi, J. Simons, D. Douglas Oracle, 9515 Towne Centre Drive, San Diego, CA USA 92121 E. M. Chow, D. Debruyker, B. Cheng, G. Anderson Palo Alto Research Center (PARC), 3333 Coyote Hill Road, Palo Alto, CA USA 94304 Flexible, stress-engineered spring interconnects is a novel technology potentially enabling room temperature assembly approaches to building highly integrated and multi-chip modules (MCMs). Such interconnects are an essential solder-free technology facilitating the MCM package diagnostics and rework. Previously, we demonstrated the performance, functionality, and reliability of compliant micro-spring interconnects under temperature cycling, humidity bias and high-current soak. Currently, we demonstrate for the first time the package with the 1st level conventional fine pitch C4 solder bump interconnects replaced by the arrays of microsprings. A dedicated CMOS integrated circuits (ICs) have been assembled onto substrates using these integrated microsprings. Metrology modules on the ICs are designed and used to characterize the connectivity and resistance of each micro-spring site.