作为典型的透明导电氧化物,CdO. 剂离子半径和电子结构对电荷传输和频段结构的影响的系统学
Yu Yang1, Shu Jin, Julia E Medvedeva
1Department of Chemistry, Materials Research Center, Northwestern University, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|June 16, 2005
概括
用添加的氧化 (CYO) 薄膜具有出色的光学透明度和导电性. 在透明导电氧化物中的应用中,Y注增强了光带间隙,在1.2-1.3%的注下达到最佳性能.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 薄膜技术 薄膜技术
背景情况:
- 透明导电氧化物 (TCO) 对光电子设备至关重要.
- 氧化 (CdO) 是一个有前途的TCO材料,但它的特性可以通过剂调整.
- (Y) 兴奋剂提供了一种修改CdO电气和光学特性的途径.
研究的目的:
- 为了合成和表征添加CdO (CYO) 薄膜.
- 调查Y兴奋剂对CdO结构,电气和光学性能的影响.
- 使用实验和理论方法,将Y兴奋剂与其他兴奋剂 (In, Sc) 的效果进行比较.
主要方法:
- 金属有机化学蒸汽沉积 (MOCVD) 用于薄膜生长.
- 用X射线衍射 (XRD) 来进行相位结构和微观结构分析.
- 光学传导率和电导率的测量.
- 电子带结构计算.
主要成果:
- 在玻璃和MgO100) 基板上成功生长了纯相,多晶CYO薄膜.
- 电影在可见范围内显示>80%的光学传导率.
- Y兴奋剂扩大了带间距到3.27 eV (Burstein-Moss转移).
- 最佳的Y兴奋剂 (1.2-1.3%) 产生了8,540 S/cm (玻璃) 和17,800 S/cm (MgO100) 的导电率.
- 剂的离子半径和电子结构显著影响网格参数,载体移动性和效.
结论:
- 兴奋剂有效地提高了基于CdO的透明导电氧化物的性能.
- 这项研究提供了有关CdO系统的结构-属性关系的见解.
- 实验和理论发现强调了选择剂对于优化TCO特征的重要性.
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