Realization of Visible‐Light Detection in InGaZnO Thin‐Film Transistor via Oxygen Vacancy Modulation through N<sub>2</sub> Treatments
Xindi Xu, Meng Zhang, Yuyang Yang, Lei Lü, Lin Feng, Man Wong, Hoi Sing Kwok
Abstract
Abstract InGaZnO (IGZO) thin‐film transistors (TFTs) have gained widespread use in active matrix (AM) displays due to their decent field‐effect mobility and low off current. However, the wide bandgap of IGZO limits their application in visible light detection. This study presents an industry process‐compatible method to achieve visible light detection in IGZO TFTs through N 2 treatment during the sputtering and annealing process for the first time. A comparison with control IGZO TFTs shows that the N 2 ‐treated IGZO TFTs exhibit a high responsivity of 0.66 A W −1 and detectivity of 5.40 × 10 14 Jones for visible light detection. Based on X‐ray photoelectron spectroscopy analysis and technology computer‐aided design simulations, a model, focusing on oxygen vacancy modulation, is proposed to explain the visible‐light sensitivity in IGZO TFTs with N 2 treatment. This work opens up new possibilities for the integration of IGZO photodetector into AM display panels to realize in‐cell environmental detection and biometric recognition.