Design and analysis of a novel fine pitch and highly stretchable interconnect

Purpose - The purpose of this paper is to demonstrate electromechanical properties of a new stretchable interconnect design for fine pitch applications in stretchable electronics. Design/methodology/approach - A patterned metal interconnect with a zigzag shape is adhered on an elastomeric substrate. In situ home-built electromechanical measurement is carried out by the four-probe technique. Finite element method is used to analyze the deformation behavior of a zigzag shape interconnect under uniaxial tensile loading. Findings - The electrical resistance remains constant until metal breakdown at elongations beyond 40 percent. There is no significant local necking in either the transverse or the thickness direction at the metal breakdown area as shown by both scanning electron microscopy micrographs and resistance measurements. Micrographs and simulation results show that a debonding occurs due to the local twisting of a metal interconnect, out-of-plane peeling, and strain localized at the crest of a zigzag structure. Originality/value - In this paper, the zigzag shape is, for the first time, proven as a promising design for stretchable interconnects, especially for fine pitch applications.