Electrical Characterization of the Self-Heating Effect in Oxide Semiconductor Thin-Film Transistors Using Pulse-Based Measurements

The self-heating effect (SHE) in top-gate In–Ga–Zn–O (IGZO) thin-film transistors (TFTs) was examined systematically using short electrical pulse measurement methods. The temperature dependence of the pulse measurements of IGZO TFTs revealed a significant increase in temperature during the measurements, suggesting that conventional measurements can overestimate the device performance significantly. The effective temperature was introduced and extracted for IGZO TFTs at various heating powers and ambient temperatures. The short sampling time was determined to be a key in characterizing the intrinsic device properties that are not influenced by the SHE. The cooling behavior after self-heating was also examined using multipulse measurements. Because heating and cooling are significant even in a very short time, it is essential to consider the operation condition of the devices when characterizing TFTs to estimate the precise performance and reliability in a real operation.