Effect of Humidity on Properties of Aqueous-Processed Tb-Doped Indium Oxide Thin-Film Transistors

Lee

ACS Appl. Electron. Mater.

et al. 2023

Here, we investigate the effect of increasing temperature on threshold voltage (V TH ) stability in self-aligned coplanar amorphous indium-zinc-tin oxide (a-IZTO) thin-film transistors (TFTs). An analytical model of the temperature dependency of V TH stability reveals the importance of device geometry and subgap density-of-state (DOS) reductions in highly stable a-IZTO TFTs. The validity of the analytical model is confirmed using experiments and technology computer-aided design simulations to predict quantitative relationships under various shifts in temperatures, subgap DOS, and V TH . The role of hydrogen impurity in performance and V TH stability is also examined. The incorporation of hydrogen in a-IZTO channels improves TFT performance and thermal stability (ΔV TH /ΔT = 3.18 mV/K) due to hydrogen's role as a passivation center. However, excessive incorporation of hydrogen increases subgap DOS distribution, causing a slight deterioration in thermal stability (ΔV TH /ΔT = 3.31 mV/K). This suggests that hydrogen can be converted from a shallow donor to an acceptor-like deep trap state. Our findings inform future designs of stable oxide semiconductor TFTs in terms of thermal stability in emerging organic light-emitting diode, augmented and virtual reality, memory, logic, and monolithic three-dimensional applications.

Section: Resultsmentioning

confidence: 99%

Theoretical Modeling of a Temperature-Dependent Threshold-Voltage Shift in Self-Aligned Coplanar IZTO Thin-Film Transistors

Lee

ACS Appl. Electron. Mater.

et al. 2023

“…8 Thus, researchers have proposed many methods to improve the performance of In 2 O 3 TFTs. For example, the performance of TFTs has been improved by selecting suitable dopants as carrier suppressors such as Tb, 9 B, 10 Sr, 11 and Ni. 12 Standard electrode potential (SEP), electronegativity and the ability to bind oxygen are the main criteria for selecting a suitable dopant.…”

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Electrical performance of La-doped In₂O₃ thin-film transistors prepared using a solution method for low-voltage driving

Du,

Tuokedaerhan,

Zhang

2024

RSC Adv.

Physica Status Solidi (a)

“…[11] In general, PBS and PBTS induce a positive threshold voltage shift (ΔV TH ), while NBS and NBIS lead to a negative ΔV TH in oxide semiconductor TFTs. [9,[12][13][14] Currently, NBIS instability is the main critical issue for display applications, especially for switching TFTs that are continuously negatively biased and exposed to light during their operation. [1,3] It is widely accepted that the NBIS instability in oxide semiconductor TFTs is closely associated with deep-subgap defects in oxide semiconductors, which are primarily caused by excess oxygen vacancies.…”

mentioning

confidence: 99%

Improved Performance and Bias Stability of Indium‐Tin‐Zinc‐Oxide Thin‐Film Transistors Enabled by an Oxygen‐Compensated Capping Layer

Xiao,

Jin,

Lee

et al. 2023

In this work, the effects of oxygen compensated capping layer (CCL) on the electrical performance and stability of indium‐tin‐zinc‐oxide (ITZO) thin‐film transistors (TFTs) are investigated. Two different channel structures, namely single and dual channels, are tested for the ITZO TFTs. The dual‐channel layer is created by depositing an oxygen CCL on the oxygen uncompensated channel layer (UCL), while the single‐channel layer consists only of the oxygen UCL. It is found that the oxygen CCL is critical for enhancing the electrical properties of dual‐channel ITZO TFT and its stability under different stress modes such as dynamic stress, positive bias temperature stress, and negative bias illumination stress. The dual‐channel ITZO TFT exhibits a saturation field‐effect mobility of 16.69 cm2 V‐1s‐1, a threshold voltage of 6.80 V, and a sub threshold swing of 0.22 V dec‐1. Furthermore, it is revealed that the higher metal‐oxide concentration, and fewer defects in the dual‐channel, which lead to enhanced electrical performance and stability of the device. This work demonstrates the potential of utilizing the oxygen CCL for highly reliable operation of oxide semiconductor TFTs.This article is protected by copyright. All rights reserved.