Abnormal Output Characteristics of p-Type Low Temperature Polycrystalline Silicon Thin Film Transistor Fabricated on Polyimide Substrate

• Main Authors: Seok-Woo Lee, Chang Bum Park, Pyo Jin Jeon, Sung-Wook Min, June Yeong Lim, Han Sol Lee, Jae-Sung Yoo, Soon Sung Yoo, Seongil Im
• Format: Article
• Language: English
• Published: IEEE 2016-01-01
• Series: IEEE Journal of the Electron Devices Society
• Subjects: Thin-film transistor (TFT),; LTPS; self-heating effect; hot carrier effect; polyimide (PI); flexible
• Online Access: https://ieeexplore.ieee.org/document/7302517/

We report on an abnormal output characteristics in p-type low temperature polycrystalline silicon thin-film transistors fabricated on polyimide (PI); negative differential conductance behavior is often observed in saturation region of drain current from large width devices. To understand such abnormal output characteristics, device dimension dependence was studied in a systematic way. As a result, we found that enhanced self-heating is mainly responsible originating from the poor thermal conductivity of PI substrate. A related degradation model is also proposed.