材料科学
带隙
脉冲激光沉积
紫外线
椭圆偏振法
谱线
光电子学
费米能级
宽禁带半导体
激光器
直接和间接带隙
分析化学(期刊)
薄膜
光学
化学
纳米技术
电子
物理
色谱法
量子力学
天文
作者
Nhan V. Nguyen,Nam V. Nguyen,Jason Hattrick‐Simpers,Oleg A. Kirillov,Martin L. Green
摘要
Transparent conducting oxides are electrically conductive materials with high optical transmittance in the visible region of the spectrum and are useful in a wide range of applications. In this study, the optical spectra of a set of single-phase transparent conducting oxides TiO2, ZnO, and SnO2 grown by pulse laser deposition are measured by vacuum ultraviolet spectroscopic ellipsometry and the optical bandgaps are determined to be 3.30 ± 0.05 eV, 3.13 ± 0.05 eV, and 3.95 ± 0.05 eV, respectively. Differences between these values and previous measurements are discussed. SnO2 and ZnO optical responses at the bandgap reveal that they are a direct bandgap, while TiO2 appears to show an indirect type. For the interfacial electronic characteristics, the internal photoemission measurement shows that the electronic barriers of these naturally n-type-doped metal oxides adjacent to an Al2O3 layer originate from the Fermi level in their conduction bands. The band offset determination shows that the barrier heights are similar and have a small internal field dependence. The work functions are then estimated from the measured barrier heights.
科研通智能强力驱动
Strongly Powered by AbleSci AI