Linear organic transistor based temperature sensor between 230 and 330 K

In this paper, the stability and the linearity of a single-ended temperature sensor, consisting of a diode-connected organic thin film transistor (OTFT), are investigated in a wide temperature range from 230 to 330 K. While the sensor fabricated on silicon dioxide (SiO2) shows instability due to threshold voltage shift affected by temperature, the device in which SiO2 is covered by a polymeric buffer layer shows a good stability with an error lower than 1%. It also achieves a linearity of 99.95% when biased with a current of 22 nA, with a high sensitivity of about 100 mV/K, exceeding that of silicon-based sensors. The model used to describe the device behavior demonstrates that the linearity is given by the compensation of two non-linear functions of temperature.