在以化物为基础的发光器件中进行载体重组:多声波过程,激发缺陷和混乱的异态接口
Grigorii Savchenko1, Evgeniia Shabunina1, Anton Chernyakov2
1Ioffe Institute, 26 Politekhnicheskaya, St Petersburg 194021, Russia.
Nanomaterials (Basel, Switzerland)
|July 13, 2024
概括
纳米材料障碍 (DND) 显著影响化物发光二极管 (LED) 的性能,与外部量子效率 (EQE) 的降低相关. 激发缺陷 (EDs) 和它们与载体的相互作用导致效率下降和光谱变化.
科学领域:
- 固态物理 固态物理
- 材料科学 材料科学 材料科学
- 光电学是指光电子产品.
背景情况:
- 化物发光二极管 (LED) 对于照明和显示器至关重要.
- 了解重组过程是提高LED效率和性能的关键.
- 纳米材料障碍 (DND) 和激发缺陷 (EDs) 与LED效率限制有关.
研究的目的:
- 调查化物LED中电光特性和DND之间的相关性.
- 阐明DND和EDs在效率下降和光谱特征中的作用.
- 确定载波与ED交互的机制及其对LED性能的影响.
主要方法:
- 研究了从270到540nm发射的化物LED,具有不同的外部量子效率 (EQE).
- 在量子井 (QW) 和异质接口中分析了纳米材料障碍 (DND) 的程度.
- 通过光谱和效率测量,研究了与激发缺陷 (EDs) 的载体相互作用.
主要成果:
- 在LED电光特性和DND.之间发现了显著的相关性.
- 减少EQE与增加的DND和ED度有关.
- 确定了两种与EDs的载体相互作用机制,影响电解发光光谱和EQE.
- 这些机制有助于效率下降和可逆的LED退化.
结论:
- DND和ED是限制不同波长的化物LED性能的关键因素.
- 通过EDs捕获和电离的多声波载体显著影响EQE和效率下降.
- 了解这些重组过程对于设计高效,稳定的化物LED至关重要.
相关概念视频
Carrier Generation and Recombination
560
Carrier generation is the process by which electron-hole pairs (EHPs) are created within the semiconductor. In direct-bandgap semiconductors, such as gallium arsenide (GaAs), this occurs efficiently when energy absorption prompts valence electrons to leap into the conduction band, leaving behind holes.
This process is given by the generation rate G and is efficient due to the conservation of momentum between the valence band maximum and conduction band minimum.
Indirect generation involves an...
This process is given by the generation rate G and is efficient due to the conservation of momentum between the valence band maximum and conduction band minimum.
Indirect generation involves an...
560
Deactivation Processes: Jablonski Diagram
635
Luminescence, the emission of light by a substance that has absorbed energy, is a process that involves the interaction of molecules with light. The energy-level diagram, or Jablonski diagram, is a graphical representation of these interactions, illustrating the various states and transitions a molecule can undergo. In a typical Jablonski diagram, the lowest horizontal line represents the ground-state energy of the molecule, which is usually a singlet state. This state represents the energies...
635
Photoluminescence: Fluorescence and Phosphorescence
2.0K
Photoluminescence is a process where a molecule absorbs light energy and re-emits it in the form of light. This phenomenon occurs when a substance absorbs photons, promoting its electrons to higher energy level excited states, followed by a relaxation process in which the electrons return to their original ground state energy levels and emit light. Photoluminescence is widely observed in various materials, including semiconductors, and organic and inorganic compounds.
A pair of electrons in a...
A pair of electrons in a...
2.0K
Types of Semiconductors
585
Intrinsic semiconductors are highly pure materials with no impurities. At absolute zero, these semiconductors behave as perfect insulators because all the valence electrons are bound, and the conduction band is empty, disallowing electrical conduction. The Fermi level is a concept used to describe the probability of occupancy of energy levels by electrons at thermal equilibrium. In intrinsic semiconductors, the Fermi level is positioned at the midpoint of the energy gap at absolute zero. When...
585


