Design, Fabrication, and Characterization of Dense Compressible Microinterconnects

This paper presents gold passivated NiW compressible microinterconnects (CMIs) with 75 μm height and 150 μm in-line pitch. The CMIs are batch fabricated using CMOS-compatible processes. The fabricated CMIs have a measured compliance of up to 13.12 mm/N and demonstrate 45 μm elastic vertical range of motion. Moreover, the CMIs are shown to return to their original geometrical profile after several deflections and consequently are able to maintain contact with their corresponding pads at all times. The measured four-point resistance of a CMI, which includes contact resistance, is as low as 176.3 mΩ.