Han Youngmin, Lee Dong Hyun, Cho Eou-Sik, Kwon Sang Jik, Yoo Hocheon
Department of Electronic Engineering, Gachon University, Seongnam 13120, Republic of Korea.
Micromachines (Basel). 2023 Jul 8;14(7):1394. doi: 10.3390/mi14071394.
Oxygen vacancies are a major factor that controls the electrical characteristics of the amorphous indium-gallium-zinc oxide transistor (a-IGZO TFT). Oxygen vacancies are affected by the composition ratio of the a-IGZO target and the injected oxygen flow rate. In this study, we fabricated three types of a-IGZO TFTs with different oxygen flow rates and then investigated changes in electrical characteristics. Atomic force microscopy (AFM) was performed to analyze the surface morphology of the a-IGZO films according to the oxygen gas rate. Furthermore, X-ray photoelectron spectroscopy (XPS) analysis was performed to confirm changes in oxygen vacancies of a-IGZO films. The optimized a-IGZO TFT has enhanced electrical characteristics such as carrier mobility (μ) of 12.3 cm/V·s, on/off ratio of 1.25 × 10 A/A, subthreshold swing () of 3.7 V/dec, and turn-on voltage (V) of -3 V. As a result, the optimized a-IGZO TFT has improved electrical characteristics with oxygen vacancies having the highest conductivity.
氧空位是控制非晶铟镓锌氧化物晶体管（a-IGZO TFT）电学特性的主要因素。氧空位受a-IGZO靶材的组成比和注入氧流量的影响。在本研究中，我们制备了三种具有不同氧流量的a-IGZO TFT，然后研究了电学特性的变化。进行原子力显微镜（AFM）分析以根据氧气速率分析a-IGZO薄膜的表面形貌。此外，进行X射线光电子能谱（XPS）分析以确认a-IGZO薄膜氧空位的变化。优化后的a-IGZO TFT具有增强的电学特性，例如载流子迁移率（μ）为12.3 cm/V·s，开/关比为1.25×10 A/A，亚阈值摆幅（）为3.7 V/dec，开启电压（V）为-3 V。结果，优化后的a-IGZO TFT具有改善的电学特性，其氧空位具有最高的电导率。
