Autonomous Oxygen Doping of Intrinsically Stretchable Polymer Semiconductors for Skin Electronics

The doping systems for intrinsically stretchable polymer semiconductors are remained an emerging challenge in advancement of skin electronics despite a significant development for few decades. Here, we introduce an oxygen doping system enabled by ambient oxygen molecules in air as dopants for intrinsically stretchable polymer semiconductors. The oxygen molecules can act as acceptor like dopants when they chemically adsorbed on the semiconductors through a diffusion-controlled process influenced by oxygen partial pressure and humidity. The controlled oxygen doping condition significantly increases the hole concentration of the semiconductors by two orders of magnitude (3.37×10¹⁷ cm^-2), which leads to enhanced almost all electrical performances such as transconductance, field-effect mobility, and on/off ratio of the field-effect transistors with superior air stability. Demonstrating the practical application of our approach, we fabricate active-matrix arrays and logic devices such as inverter, NOR, and NAND gates with the oxygen-doped stretchable polymer semiconductors, exhibiting excellent operational reliability under 30% biaxial strain. This advancement marks a significant step toward the industrialization of high-performance skin electronics.