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 stretch-ability when constructing transistor arrays. We aim to construct highly stretch-able 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 bot-tom polyimide layers, achieving robustness under repeated tensile strain. Dif-ferent 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 con-siderable performance degradation. As our TFTs are fabricated using common materials from display manufacturing, our development and findings may sub-stantially benefit stretchable electronic industries where high reliability is required for large-area panels.

Keywords

• oxide semiconductor
• serpentine structure
• stretchable interconnect
• thin-film transistor array