在InAs合体量子点固体之间调整连接的分子表面编程
Maral Vafaie1, Amin Morteza Najarian1, Jian Xu1
1The Edward S. Rogers Department of Electrical and Computer Engineering, University of Toronto, Toronto, ON M5S 3G4, Canada.
概括
无重金属的化环状量子点 (CQD) 是为改进的短波长红外光探测器设计的. 分子表面修饰器成功调整了能量水平,提高了设备的性能并减少了暗电流.
科学领域:
- 材料科学 材料科学 材料科学
- 光电学是指光电子产品.
- 纳米技术 纳米技术
背景情况:
- 没有重金属的III-V体量子点 (CQD) 对光电子有前景.
- 大直径的化 (InAs) CQD 能够实现短波红外 (IR) 应用.
- 之前对InAs CQD光二极管的尝试由于能量水平错位而失败.
研究的目的:
- 为了提高光探测器性能,使用INA CQD开发一个整形连接点.
- 为了克服基于INA的CQD设备中的能量水平错位问题.
- 使用分子表面修饰器调整INA CQD的电子特性.
主要方法:
- 合成的大直径的InaCQDs.
- 使用分子表面修饰剂 (碳酸盐和硫酸盐连接体) 来调整CQD能量水平.
- 利用光物理研究和密度函数理论 (DFT) 进行分析.
- 制造和测试的光二极管设备.
主要成果:
- 开发了具有向上移动的价值带段的InAs CQD (最浅的4.8 eV).
- 在>1μm时实现了35%的外部量子效率 (EQE) 的光二极管.
- 暗电流密度降低至<400 nA cm-2 .
- 与之前的III-V CQD光检测器相比,已经证明了显著的性能改进.
结论:
- 分子表面的修改是有效的调整INA的CQD能量水平.
- 开发的InAs CQD光二极管显示了用于短波长红外探测的增强性能.
- 这项工作推动了无重金属III-V CQD光电子领域的发展.
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