Crack Observation of Wave-Shaped Metal Track on Stretchable Substrate

Abstract

This paper reports observation and analysis of crack propagation on wave-shaped metal tracks on stretchable substrates. Copper tracks with various thicknesses and amplitudes of wave-shapes were fabricated by photolithography on polyurethane substrates. Crack characteristics in the tracks under stretching load of the samples were investigated with respect to elongation at break, crack width, and the number of induced cracks. As result, the elongation when the first break occurs increases with track thickness. The crack width increases with the elongation of the samples at the first break. The gradient of the number of the cracks decreased as the track thickness increased.