Characterizing and Modelling of the BTI Reliability in IGZO-TFT using Light-assisted I-V Spectroscopy
Zhicheng Wu, Adrian Chasin, J. Franco, Subhali Subhechha, Harold Dekkers, Y V Bhuvaneshwari, A. Belmonte, Nouredine Rassoul, Michiel J. van Setten, V. Afanas'Ev, Romain Delhougne, B. Kaczer, Gouri Sankar Kar
Abstract
The sub-gap Density-of-State (DoS) in IGZO thin-film transistors (TFT) is systematically investigated using a newly developed Light-assisted I-V Spectroscopy (LaIVs). The technique quantifies the sub-gap DoS of pristine IGZO device and how they evolve with the electrical stress. By combining LaIVs with a model of the entire I-V, charge trapping in the gate-dielectric defects and sub-gap DoS changes during Positive Bias Temperature Instability (PBTI) are decoupled. Their time kinetics and voltage acceleration factors are extracted, allowing to project the I-V degradations to any stress time and voltages.