Cracking behavior of thin gold strip deposited on polycarbonate plate under Cyclic and stepwisely-increased tension

Abstract

Abstract. Thin metal films deposited on polymers have been attracting much attention in flexible electronics. Various combinations of film and polymer substrate are expected to be developed. In this paper, deformation and fracture of thin metal film on polymer substrate was briefly analysed and the influencing factors were summarized. After that, focusing on the shape and thickness of thin metal film on polymer substrate, cracking behavior of small roundedrectangular thin gold films called "strips" with a thickness less than one micrometer was observed under cyclic and stepwisely-increased trapezoidal tensions. The strips were deposited on a polycarbonate plate specimen, and wide and narrow strips with different thickness were prepared for the tests. The cracking behaviour was successfully observed and the increasing rate of crack number with the load or strain was examined. Since most cracks were initiated from the small defects, the crack initiation behavior was correlated with the distribution of defects.

Cracking effects in squashable and stretchable thin metal films on PDMS for flexible microsystems and electronics

“…In an effort to understand the experimental observations concerning the cracking of the longitudinally orientated lines one can look to existing models for explanations. It is well known that a thin brittle film—deposited onto, and subsequently supported on a flexible substrate—can fracture into a pattern of parallel cracks 49 , 50 , 57 – 63 . This cracking can be of a spontaneous nature 50 , 58 —initiated by random process defects 64 , or controlled for practical applications—using deliberately pre-patterned defects 65 , 66 or by the presence of boundaries 44 .…”

Ultra-stretchable active metasurfaces for high-performance structural color

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