摘要
通过对不同In含量的InGaN/GaN量子阱材料的变温光致发光(PL)谱进行实验分析,得出样品激活能和PL谱峰值能量随温度变化的S形曲线中拐点温度与In含量的关系。说明对于我们的样品,这种S形曲线并不是来源于量子限制Stark效应(QCSE),而是与量子阱中In团簇有关。对比结果表明,含In量越多的材料其局域的能量越大,由热扰动脱离局域所需要的温度越高。
Temperature-dependent photoluminescence（PL） of InGaN/GaN multiple quantum wells（MQWs） is studied.Three samples have different percentage composition of In： 10%,14% and 17%.With increasing temperature,we can observe ＂S-shaped＂ behavior of the peak energy for all three samples.Because the second temperature turn of the ＂S-shaped＂ curves are different for each samples,and the blueshift energy of 10 meV in our samples is less than the energy shift result from QCSE,the S-shape is unrelated with QCSE.By using multi-channel Arrhenius plot formula,the samples’ activation energies are calculated,which stand for the level of localized In-cluster.And it is found that both the activation energies and the second temperature turn of the ＂S-shaped＂ curves increase with increasing the content of indium for three samples.This phenomenon can be demonstrated by the reason that the sample which containing much In has lager activation energy,the photo-carriers need much thermal energy to get out of the local potential minima induced by In-cluster.These results further illustrate that the emission of InGaN/GaN multiple quantum wells is due to the radiative recombination of excitons localized in potential minima induced by In-cluster.
出处
《发光学报》
EI
CAS
CSCD
北大核心
2010年第6期864-869,共6页
Chinese Journal of Luminescence
基金
国家自然科学基金(60776042)
国家重大科学研究计划(2009CB930504)资助项目
关键词
In团簇
INGAN
变温PL
激活能
In cluster
InGaN
temperature-dependent PL
activation energy
