Investigation of the Self-Heating Effect in High Performance Organic TFTs With Multi-Finger Structure

This study investigated the impact of Joule heating under high current operation on multi-finger organic thin film transistors (OTFTs). The degradation was examined for a range of devices with different numbers of fingers (N = 4, 6, and 10). Due to the heat accumulation during operation, significant electrical degradation was observed at high currents. Under bias stress, with increasing number of fingers, the electrical characteristics exhibited different degrees of degradation, and an abnormal hump was observed in devices with 10 fingers. To examine the effect of self-heating, OTFTs were prepared on two substrates, polyimide and glass, and the causes of degradation were investigated at both room temperature and low temperatures. In addition, AC operation was proposed. Finally, a Silvaco TCAD simulation was made to model the device self-heating and illustrate the effect of the number of fingers on the bias stress.