Present understanding of Eu luminescent centers in Eu-doped GaN grown by organometallic vapor phase epitaxy
Present understanding of Eu luminescent centers in Eu-doped GaN grown by organometallic vapor phase epitaxy
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DOI:
10.7567/jjap.53.05fa13
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发表时间:
2014-05-01
影响因子:
1.5
通讯作者:
Dierolf, Volkmar
中科院分区:
文献类型:
--
作者:
Fujiwara, Yasufumi;Dierolf, Volkmar
We have succeeded in growing Eu-doped GaN (GaN:Eu) layers with high crystalline quality by organometallic vapor phase epitaxy, and have demonstrated a low-voltage current-injected red emission from a light-emitting diode (LED) using the GaN: Eu layer with an applied voltage of as low as 3V. By optimizing growth conditions and device structures, the light output power has increased steadily to up to sub-mW at an injected current of 20 mA. For further improvement of the output power, Eu luminescent centers have been spectroscopically investigated in GaN: Eu. A variety of Eu luminescent sites and a strongly site-dependent energy transfer process were clearly revealed. The energy-transfer efficiency was markedly enhanced by codoping of Mg with Eu. A proposed model for centers with high energy-transfer efficiencies is discussed in relation to the local structure. (C) 2014 The Japan Society of Applied Physics