Emission efficiency enhanced by introduction of the homogeneous localization states in InGaN/GaN multiple quantum well LEDs
Emission efficiency enhanced by introduction of the homogeneous localization states in InGaN/GaN multiple quantum well LEDs
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通过在 InGaN/GaN 多量子阱 LED 中引入均匀局域态来提高发射效率
DOI：
10.1016/j.allcom.2016.04.259
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发表时间：
2016
影响因子：
6.2
通讯作者：
Du G. T.
中科院分区：
文献类型：
--
作者：
Yang J.;Zhao D. G.;Jiang D. S.;Chen P.;Zhu J. J.;Liu Z. S.;Liu J. P.;Zhang L. Q.;Yang H.;Zhang Y. T.;Du G. T.
采用金属有机物化学气相沉积（MOCVD）技术，在不同温度下生长了一系列结构相似的InGaN/GaN多量子阱（MQW）LED，并对其结构和光学特性进行了详细的研究。结果发现，当InGaN量子阱的生长温度从820 °C降低到770 °C时，LED的输出功率显著增加。这是由于局域化态随生长温度的降低而变化的结果。在较低温度（LT）生长的InGaN/GaN多量子阱中，大的和高铟含量的富In区域伴随缺陷的形成被更好地抑制，而更浅和更均匀的局域态的形成，表现为有效的发光中心，更有利。因此，在LT生长的InGaN/GaN多量子阱LED中观察到增强的发射强度。
A series of InGaN/GaN multi-quantum well (MQW) LEDs are grown by using metalorganic chemical vapor deposition (MOCVD) with similar structure but at different temperature, their structural and optical characteristics are investigated in detail. It is unexpectedly found that the output power of LEDs increases markedly when the growth temperature of InGaN QWs decreases from 820 °C to as low as 770 °C. This is attributed to the variation of localization states with the decrease of growth temperature. In the lower temperature (LT) grown InGaN/GaN MQWs, the formation of large and high indium content In-rich regions accompanied with defects is better suppressed, while the formation of shallower and more homogeneous localization states, behaving as effective luminescence centers, are more favored. Therefore, enhanced emission intensity is observed in the LT-grown InGaN/GaN MQW LEDs.