Film Adhesion of Flexible Electronics Influenced by Interlayers
As flexible electronics emerge for applications such as medical sensors and foldable displays, there is a need to understand the interfacial behavior between the conducting elements and the compliant polymer substrate that the devices are prepared on. Compression-induced delamination is a technique that uses the buckling dimensions to evaluate the interfacial adhesion of materials on flexible substrates quantitatively. This study shows that spontaneous buckles are formed in gold (Au) films, which are deposited without an interlayer. Conversely, external loading is required to delaminate the Au film with the tantalum (Ta) adhesion layer indicating higher adhesion energy.