报告题目：Importance of interfaces in semiconductor devices based on low-dimensional materials

报告人：Prof. Yutaka Ohno
（Institute of Materials and Systems for Sustainability,Nagoya University,Japan yohno@nagoya-u.jp）

时间：2025年2月28日（周五），下午4:00

地点：师昌绪楼403室

摘要：

In semiconductor devices,it is no exaggeration to say that the possibility of practical application is determined by the ability to control the interface. In silicon,the excellent insulator/semiconductor interface obtained through thermal oxidation has made it possible to manufacture highly reliable large-scale integrated circuits,and the high-k gate insulator introduced with miniaturization has been achieved based on an understanding and control of interface phenomena,contributing to ultra-high density integration and low power consumption.

In contrast,in FETs using carbon nanotubes (CNTs) and 2D materials,it is known that there is a significant degree of instability in the characteristics (hysteresis and current drift) and low-frequency noise due to traps near the gate insulator interface,and that the carrier polarity and threshold voltage change due to fixed charges near the interface. However,there are no examples of completely removing defects and contamination from the surface of the material to form a clean,controlled interface,and so the design and demonstration experiments of integrated circuits are being carried out using ready-made characteristics.

In this seminar,the interface characteristics of CNT TFTs,in particular,the structure,electrical property,and traps of the oxide/CNT interface,based on various characterization methods. We also report a flexible CNT TFT with an inorganic polymer as the gate insulator,which show ionic conduction at very low-frequency. The result suggests a new possibility for the suppression of low-frequency noise through the screening of trap charges by accumulated ions.

报告人简介：

大野雄高（Yutaka Ohno），日本名古屋大学工学研究部教授，可持续发展材料与系统研究所、未来电子创新集成研究中心主任，日本物理学会、应用物理学会、电子信息与通信工程学会、富勒烯和纳米管研究学会以及美国化学学会成员，获得3项学术奖励。主要从事碳纳米管电子器件的物性及机制研究。他提出了接触金属功函数方法和栅氧化层引入电荷的方法，实现了晶体管极性的有效控制，成为基于碳纳米管CMOS器件的标准技术。他开发出基于碳纳米管的可塑性电子器件，获得了高性能的薄膜晶体管，其迁移率比有机及其他类型器件提高几个数量级。Ohno教授发表期刊学术论文129篇，引用超过3000次，h因子为31，在国际会议作邀请报告73次，日本学术会议邀请报告44次，9次大会特邀报告。