title: Meniscus-confined three-dimensional electrodeposition for direct writing of wire bonds.
abstract: Continued progress in the electronics industry depends on downsizing, to a few micrometers, the wire bonds required for wiring integrated chips into circuit boards. We developed an electrodeposition method that exploits the thermodynamic stability of a microscale or nanoscale liquid meniscus to "write" pure copper and platinum three-dimensional structures of designed shapes and sizes in an ambient air environment. We demonstrated an automated wire-bonding process that enabled wire diameters of less than 1 micrometer and bond sizes of less than 3 micrometers, with a breakdown current density of more than 10(11) amperes per square meter for the wire bonds. The technology was used to fabricate high-density and high-quality interconnects, as well as complex three-dimensional microscale and even nanoscale metallic structures.
authors.affiliation: Department of Mechanical Science and Engineering, University of Illinois, 1206 West Green Street, Urbana, IL 61801, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Hu
authors.forename: Min-Feng
authors.initials: MF
authors.lastname: Yu