Compliant cantilevered spring interconnects for flip-chip packaging

A new highly-compliant cantilevered spring interconnect is being developed to enable a fine-pitch, high density I/O architecture for the next generation chip and probing technology. This technology meets the requirements of National Technology Roadmap for Semiconductor (NTRS) for 2012 and beyond. Based on its unique structure, a new contact mode - sliding contact with no solder is being tested. To understand the reliability of the package with this novel compliant spring interconnect structure and the typical behavior of the sliding contact, test vehicles with different orientations of the cantilevered springs (21 /spl mu/m pitch) have been fabricated, assembled and subjected to thermal cycling test. In-situ resistance and temperature measurements have been conducted. Material characterization of underfill has also been conducted.