Observing the Delamination Interface in Multi Layered Thin Films with a MgAg Alloy Top Layer and Organic Semiconductor under Layers on a Flexible Substrate

摘要

In this study, tensile tests of single layer and multi-layer specimens were conducted based on Al or MgAg alloy as metal electrode and tris (8-hydroxyquinolinato) aluminum or 4,4'-Bis(N-carbazolyl)-1,1'-biphenyl as lower organic layer and polyethylene naphthalate as substrate with measuring electric resistance change, then the surface and cross section were observed to investigate the occurrence of cracking and the location of delamination, finally the damage phenomenon was discussed. For cross-sectional observation, the specimens were embedded in a resin, cut with a microtome, and observed with a scanning electron microscope. As a result, the following conclusions were obtained. Further, the delamination was observed at the interfaces between the metal electrode layer and the lower organic semiconductor layer in both of the specimens. The cracks were observed in both the metal electrode layer and the lower organic semiconductor layer, but the number of cracks is larger in the electrode layer, and it has been suggested that the metal electrode layers are dominant in crack generation.