Highly sensitive interdigitated thermistor based on PEDOT:PSS for human body temperature monitoring

Abstract

This work introduces a wearable, highly sensitive human body temperature sensor. The proposed thermistor sensor employs a poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) as a temperature sensing layer and interdigitated electrodes (IDEs) from Silver nanoparticles deposited on Polyimide (PI) and Epson glossy paper substrates. The IDEs were patterned using inkjet printer Drop-on-demand PiXDRO LP50. The PEDOT:PSS layer was added by drop casting technique. The sensitivity of fabricated sensors was tested for different IDE number of fingers to investigate their response to the temperature range of 28-50 °C. The sensors performed linearly in the tested temperature range. Repeatability has been verified for five temperature measurement cycles. The achieved sensitivities are −1.462% /°C and −3.202%/°C for Epson paper and PI substrates, respectively. The sensor bendability results highlight the capability of the proposed sensor to be utilized for the wearable human body temperature reading.