Fabrication of Multilayer Interconnection Using Ultraviolet Nanoimprint Lithography

Advanced large scale integrated circuits (LSI) and smart sensor systems require nanoscale interconnection to transmit signals. In this work, an approach to realize multilayer interconnection based on ultraviolet nanoimprint lithography (UV-NIL) technology and copper electroplating is discussed. UV-NIL is a low-cost, mass-production technology. Nanoscale dot array patterns and line array patterns of nickel and copper were formed on a silicon substrate using UV-NIL in combination with electroplating. Imprinted 220 nm hole patterns and 150 nm line patterns were formed on photocurable resin with high dimensional accuracy. Using these resin patterns as a mask layer, 245 nm metal dot and 195 nm metal line array patterns were successfully fabricated by electroplating.