Stability and Performance Improvements of a-InZnSnO Thin-Film Transistor with HfO2 Gate Dielectrics by Thermal Annealing

• Main Authors: Ruo-Min Hsu, 徐若名
• Other Authors: Ching-Lin Fan
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/km66fx

碩士 === 國立臺灣科技大學 === 電子工程系 === 107 === Me tal oxide semiconductor is considered to be the most competitive TFT material for last decade. It has several advantages such as great uniformity for large size display, low fabrication temperature and low production cost. For next generation display, the TFT device need be improve, spiecially in mobility. To get higher mobility with IZTO-TFT, high-k dielectric was used as a gate insulator in TFT structure. In order to pursue greater metal oxide TFT performance, IZTO was introduced as the active layer. Becauce IZTO-TFT have higher mobility than IGZO-TFT with the same dielectric about 30 (cm2/V s). However, the material properties of indium zinc tin oxide are relatively unstable, so this paper will anneal through high temperature furnace tubes to improve the characteristics and stability of the components, and to explore the effect of high temperature furnace tube annealing on components. First, we tested the temperature and uniformity of the newly purchased high-temperature furnace tubes to determine whether the experimental environmental parameters were consistent. Next, the TFT elements were fabricated by using a shadow mask, which was conditioned by temperature, environment, and annealing time. In order to find the annealing environment parameters with the best component electrical characteristics, and explore the degradation mechanism under continuous bias stress application through the component stability test. By using C-V method capacitance value of the HfO2 insulating layer is measured, and the characteristics of the active layer and the insulating layer film are separately analyzed by XPS and AFM to prove the result of the electrical characteristic. Finally, this experiment found that annealing for one hour in a 350 degree atmosphere is the best annealing process parameter.