Large-area stretchable oxide thin-film transistor arrays with sandwiched molybdenum in serpentine structure

Abstract

Stretchable electronics are gaining attention with the development of skin-compatible health monitoring sensors and robotics applications. However, existing stretchable electronics show a tradeoff between reliability and stretchability when constructing transistor arrays. We aim to construct highly stretchable thin-film transistor (TFT) arrays with high reliability for large sensor backplanes. The fabricated structure comprises oxide TFTs and serpentine-shaped molybdenum interconnects that are sandwiched between top and bottom polyimide layers, achieving robustness under repeated tensile strain. Different materials for polyimide etch masks (i.e., aluminum, silicon nitride, and indium tin oxide) are tested. Within an 83.7 mm × 61 mm area, TFT arrays with a resolution of 25 pixels per inch can be stretched up to 30% without considerable performance degradation. As our TFTs are fabricated using common materials from display manufacturing, our development and findings may substantially benefit stretchable electronic industries where high reliability is required for large-area panels.