Internal Quantum Efficiency and Nonradiative Recombination Rate in InGaN-Based Near-Ultraviolet Light-Emitting Diodes
Internal Quantum Efficiency and Nonradiative Recombination Rate in InGaN-Based Near-Ultraviolet Light-Emitting Diodes
复制标题
DOI：
10.1143/jjap.51.072102
复制
发表时间：
2012-07-01
影响因子：
1.5
通讯作者：
Yamada, Yoichi
中科院分区：
文献类型：
--
作者：
Kohno, Takakazu;Sudo, Yasuhiro;Yamada, Yoichi
通过激发功率密度依赖性和温度依赖性光致发光（PL）光谱研究了在不同衬底上生长的三种类型的 InGaN 基近紫外发光二极管（LED）的内量子效率（IQE）。在 GaN 包覆层的带间激励和 InGaN 有源层的选择性激励下评估了 IQE。在两种激发条件下都可以清楚地观察到 IQE 和螺纹位错密度之间的相关性。此外，还通过时间分辨 PL 光谱研究了辐射和非辐射复合的动力学。通过测量温度依赖性非辐射复合寿命来评估非辐射复合率。基于具有不同螺纹位错密度的三种 LED 的 IQE 和非辐射复合率之间的相关性，讨论了我们估计 IQE 的方法的有效性。 (C) 2012 日本应用物理学会
The internal quantum efficiency (IQE) of three types of InGaN-based near-UV light-emitting diodes (LEDs) grown on different substrates was studied by excitation-power-density-dependent and temperature-dependent photoluminescence (PL) spectroscopy. IQE was evaluated under both the band-to-band excitation of GaN cladding layers and the selective excitation of InGaN active layers. A correlation between IQE and threading dislocation density was clearly observed under both excitation conditions. In addition, the dynamics of radiative and nonradiative recombinations was studied by time-resolved PL spectroscopy. The rate of nonradiative recombination was evaluated by measuring temperature-dependent nonradiative recombination lifetime. The validity of our method for estimating IQE is discussed on the basis of the correlation between IQE and nonradiative recombination rate for three LEDs with different threading dislocation densities. (C) 2012 The Japan Society of Applied Physics