Electrical level of defects in single-layer two-dimensional TiO2

作者：Xining Song, Luyuyan Hu, D. H. Li, L. Chen, Qingqing Sun, Peng Zhou, D. W. Zhang · 发表于：Scientific Reports · 年份：2015 · DOI：10.1038/srep15989 · 被引用次数：13 · 研究领域：2D Materials and Applications、Graphene research and applications、ZnO doping and properties

The remarkable properties of graphene and transition metal dichalcogenides (TMDCs) have attracted increasing attention on two-dimensional materials, but the gate oxide, one of the key components of two-dimensional electronic devices, has rarely reported. We found the single-layer oxide can be used as the two dimensional gate oxide in 2D electronic structure, such as TiO2. However, the electrical performance is seriously influenced by the defects existing in the single-layer oxide. In this paper, a nondestructive and noncontact solution based on spectroscopic ellipsometry has been used to detect the defect states and energy level of single-layer TiO2 films. By fitting the Lorentz oscillator model, the results indicate the exact position of defect energy levels depends on the estimated band gap and the charge state of the point defects of TiO2.