Improving Hot Carrier Reliability of Organic-TFTs by Extended Electrode

This work investigates the impact of source-drain-gate electrode overlap geometry on the reliability of organic thin-film transistors (OTFTs). The degradation of electrical characteristics after stress-induced hot carrier instability (HCI) is analyzed by comparing $\text{I}_{\text {D}}$ - $\text{V}_{\text {G}}$ transfer curves and C-V characteristic curves before and after the stress test. Severe degradation is observed in standard symmetry and source-extended structures, but increased reliability is observed in a drain-extended structure. A physical model is proposed to explain this behavior in the letter, and Technology Computer-Aided Design (TCAD) simulations are used to explore the electrical field distribution in the devices for further understanding.