Stretchability of Polymer-Supported ITO Serpentine Thin Films
Shixuan Yang (University of Texas at Austin), Nanshu Lu (University of Texas at Austin)
Mechanics of Thin Films and Multilayered Structures
Tue 10:45 - 12:15
Salomon 203
High-performance flexible electronics integrate high-quality inorganic electronic materials such as metal, semiconductor and oxide with polymer substrates. To minimize strains in inorganic materials under large deformation, metals and ceramics can both be patterned into serpentine structures. When the polymer substrate is stretched, the serpentines can rotate and twist to accommodate the applied deformation, resulting in minimized system-level stiffness and greatly reduced strain in the inorganic materials. Although serpentines of metal thin films have been widely studied, ceramic materials such as inorganic semiconductors and indium tin oxide (ITO, an optically transparent and electrically conductive material) have been rarely investigated. This study reveals the fundamental deformation and failure mechanisms of polymer-supported ceramic serpentines through both analytical and experimental means. ITO serpentines are patterned on both polyimide and PDMS substrates with systematically changing geometries. We found that in addition to serpentine geometry, substrate plays an important role in the stretchability of the ITO serpentines. Our experimental results have been validated and explained through finite element and semi-analytical modeling. Results from this study may provide guidelines of designing future serpentine-based stretchable electronics.