Flexible Integrated Sensors: Transverse Piezoresistance and Longitudinal Thermal Resistance of One Single Carbon Fiber Beam

Abstract Electronic skins require to integrate multiple‐sensing functions to sense stimuli from the outside environment (such as pressure, temperature, and humidity), and to distinguish the signals from the different stimuli. Here, reported is the feasibility to use only one single carbon fiber beam (CFB) to simultaneously detect pressure and temperature changes from the outside environment, and the signals from pressure and temperature stimuli can be effectively distinguished through its transverse piezoresistance and longitudinal thermal resistance. This work also reveals that the transverse piezoresistance follows the electron quantum tunneling between the carbon fibers, while the longitudinal thermal resistance follows the impurity scattering mechanism. The flexible pressure sensors, temperature sensors, and their integrated sensors can be easily constructed like blocks to use the same material CFBs, and these sensors have demonstrated unique advantages in wearable healthcare monitoring devices and electronic skin products.