Abstract

Significant progress has been made in the advancement of light-emitting devices in both the blue and the red parts of the emission spectrum. However, the quantum efficiency of green light-emitting diodes is still significantly lower as compared to blue- and red-emitting devices. This efficiency lag is commonly known as the “green gap” in the solid-state lighting industry. The efficiency issues in the green emission spectrum restrain further advancement in solid-state lighting. A combination of efficient blue, green, and red light-emitting devices is a promising solution toward efficient white light-emitting diodes. Despite the efficiency gap in the green emission, the lighting industry continues to produce relatively efficient white light-emitting diodes using down-conversion phosphors. However, the fruits of the solid-state white lighting could be fully achieved through color-mixing approaches rather through phosphor-based conversion. Therefore, to produce efficient green light-emitting diodes, their inherent issues such as the density of different types of defects and internal electric field should be reduced. In this study, we review various challenges and prospects of green light-emitting diodes. Broadly, the first part of this review explains the complex factors that degrade the performance of InGaN/GaN multiquantum well green light-emitting diodes, whereas the second part focuses on different strategies to enhance the internal quantum efficiency of green light-emitting diodes.

摘要

在发射光谱的蓝色和红色部分的发光器件的进步方面取得了重大进展。然而，与蓝色和红色发光器件相比，绿色发光二极管的量子效率仍然明显较低。这种效率滞后在固态照明行业通常被称为“绿色差距”。绿色发射光谱中的效率问题限制了固态照明的进一步发展。高效的蓝色、绿色和红色发光器件的组合是实现高效白色发光二极管的有前途的解决方案。尽管绿色发射的效率存在差距，但照明行业继续使用下转换磷光体生产相对高效的白色发光二极管。然而，固态白光照明的成果可以通过颜色混合方法而不是基于磷光体的转换来完全实现。因此，要生产高效的绿色发光二极管，应减少其固有的问题，例如不同类型缺陷的密度和内部电场。在这项研究中，我们回顾了绿色发光二极管的各种挑战和前景。从广义上讲，本综述的第一部分解释了降低 InGaN/GaN 多量子阱绿色发光二极管性能的复杂因素，而第二部分则侧重于提高绿色发光二极管内量子效率的不同策略。它们的固有问题，例如不同类型缺陷的密度和内部电场应该减少。在这项研究中，我们回顾了绿色发光二极管的各种挑战和前景。从广义上讲，本综述的第一部分解释了降低 InGaN/GaN 多量子阱绿色发光二极管性能的复杂因素，而第二部分则侧重于提高绿色发光二极管内量子效率的不同策略。它们的固有问题，例如不同类型缺陷的密度和内部电场应该减少。在这项研究中，我们回顾了绿色发光二极管的各种挑战和前景。从广义上讲，本综述的第一部分解释了降低 InGaN/GaN 多量子阱绿色发光二极管性能的复杂因素，而第二部分则侧重于提高绿色发光二极管内量子效率的不同策略。