Characteristic reliability of a hybrid-type temperature sensor using poly-Si thin-film transistors

We are developing hybrid-type temperature sensors using poly-Si thin-film transistors (TFTs). In this study, first, we evaluate the characteristic change of the off-leakage current of the TFT by changing the temperature several times. It is found that there is no historical effect even if the temperature changes very much. Next, we evaluate that by applying the actual driving condition. It is found that the valid evaluation can be obtained only by considering the pulse voltage bias. Finally, we evaluate the characteristic change of the oscillation frequency of the hybrid-type temperature sensor. It is found that the oscillation frequency increases along the time. It is thought that the change of the oscillation frequency can be explained by the characteristic change of the off-leakage current of the TFT by applying the actual driving condition.