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

Cracking and delamination behavior of small rounded-rectangular gold thin films called "strips" with a thickness less than one micrometer was observed under cyclic and stepwisely-increased trapezoidal tensions. Three strips in different directions were deposited on a polycarbonate plate specimen which was subjected to tensile loading. Straight slit and Vickers indentation were introduced as initial defects on each strip and cracking and delamination which were initiated around the defects were observed. In strips with slit, delamination was observed when introducing the slit. It was suggested that the delamination was caused by the residual stress accumulated during deposition. The growth of delamination was also observed during cyclic tension. In strips with indentation, complex cracking and delamination behavior was observed depending on the strip direction, which seemed to be attributed to the interactive effect of residual stress by deposition and external mechanical loading.