Flexible Multi-Modal Sensor for Electronic Skin

Flexible sensors have been developed over the decades due to their potential in various applications. However, recent developments in interactive user interface, healthcare device, tactile sensor, and artificial electronic skin require device with multifunctional properties such as various detection ability and good mobility. Research on such devices are still under developing. In this report, we demonstrate a flexible multimodal (pressure, temperature) sensor using embedded indium tin oxide (ITO). For the pressure sensor, the embedded ITO was adopted as a conductive layer with triple layer pyramid structure. We utilized water-soluble sacrificial layers for eco-friendly method. The triple layer pyramid-structured pressure sensor shows excellent sensitivity in dynamic range of 100 Pa to 10 kPa with high reliability of 10(5) cycles. For the temperature sensor, we used comb like structure with ITO. It shows negative temperature coefficient on resistance with good linearity. Due to the vertically stacked structure, we were able to ignore interface effect. This work present that the opportunity of transparent electrode towards flexible multimodal sensors that can be employed for various flexible applications.