高性能柔性透明金属氧化物/碳纳米管复合薄膜晶体管研究

项目名称： 高性能柔性透明金属氧化物/碳纳米管复合薄膜晶体管研究

项目编号： No.61504004

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 无线电电子学、电信技术

项目作者： 张敏

作者单位： 北京大学

项目金额： 18万元

中文摘要： 显示技术发展对新型薄膜晶体管提出了更高要求。要求薄膜晶体管反应速度快，具备较高的迁移率；优良的开关比和低功耗；柔性可弯折，其工艺需要与柔性衬底及显示面板材料工艺相兼容；材料轻薄透明，满足透光率要求。现有的薄膜在具备各自优势同时都有各自不足。在该项目中，我们创新提出和实现柔性透明的独立栅氧化铟镓锌/碳纳米管复合薄膜晶体管。通过结合碳纳米管的高迁移率、优越机械柔韧性和稳定性，以及IGZO的较成熟工艺和IGZO-金属较好的金半接触，并引入ITO电极、碳基柔性透明电极和高-K介质，优化器件结构工艺，实现同时具备高性能、柔性透明、独立开关的先进薄膜晶体管,以满足各种有源矩阵背板的要求，可应用于大面积高均匀性的柔性显示和可穿戴设备等领域。目标实现载流子迁移率为30cm2/Vs以上，为同等条件下IGZO薄膜晶体管的两倍以上，同时器件开关比为1E6以上，器件阈值电压可调，并具备较好的器件均匀性。

中文关键词： IGZO；碳纳米管；透明薄膜晶体管；沟道层；柔性

英文摘要： In recent years, the development of the display technology call out higher challenge for thin film transistor performance. The advanced thin film transistor devices require fast response, that is， the high mobility and high transmission speed; excellent on/off current ratio and low power consumption in order to meet the mobile or wearable device needs. Thin film transistors and the substrate need to be flexible, bendable, and its preparation process needs to be compatible with flexible substrate technology. The active channel material is expected to be thin and transparent as to meet the requirements of light transmission rate and to increase the aperture ratio of the display panel. The fabrication process also needs to be compatible to the panel material. Current thin film transistors have the advantages as well as their own shortcomings on performance and process. To meet the requirements above, in this project we propose to achieve independent-gate Indium-Gallium-Zinc-Oxide /carbon nanotubes (IGZO/CNT) composite thin film transistor based on mainly the sputtering process for the large-area high- uniformity applications. The transistors own high mobility, superior mechanical flexibility and stability, as well as better contact resistance by combining the advantages of carbon nanotubes and IGZO. Carrier mobility of the composite TFT is expected to be more than 30cm2/Vs, and the on/off current ratio keeps above 1E6. The channel length can cover 2µm-20µm simultaneously. Threshold voltages of the devices are adjustable and device uniformity and stability are improved by the CNT features and density. The flexible transparent electrodes and high-k dielectric will also be explored to be integrated into the novel composite devices to improve the light transmission rate and higher current, to meet the expectation of various large-area active matrix backplane applications including the flexible display, sensor networks, wearable devices etc. The composites are mainly fabricated based on sputtering process which is more easily compatible with IGZO thin film transistor process equipment and will further promote the IGZO/CNT composite material and carbon based flexible electrode toward industry applications.

英文关键词： IGZO;Carbon nanotube;Transparent thin-film transistor;Channel;Flexible