22.2: The influence of Oxygen Partial Pressure on the Performance of back‐channel‐etched a‐ZTO Thin‐Film Transistors

Abstract

In this work, we demonstrate that back‐channel‐etched a‐ZTO thin‐film transistors (TFTs) are close to realize industrial mass production. The effects of sputtering oxygen partial pressure on the electrical characteristics were mainly explored. Results indicated that both of sub‐threshold swing (SS) and field‐effect mobility (µsat) decreases as oxygen partial pressure increases, while threshold voltage (Vth) increases. The optimal TFTs exhibited the excellent performances: a modest µsat of 7.30 cm2/Vs, a suitable Vth of 5.29V and the SS of 0.41V/decade. Not only the variation of Vth shift (ΔVth) is +1.14 under PBS, but also ΔVth is ‐0.56 under NBS. Compared with IGZO channel layer, the promising ZTO material is abundant and non‐toxic. Therefore relevant TFTs prospectively contribute to reduce industrial production costs and environmental protection.