多层InA s量子点的光致发光研究  

Photoluminescence of Multilayer InAs Quantum Dots

作　　者：孔令民[1] 蔡加法[1] 陈厦平[1] 朱会丽[1] 吴正云[1] 牛智川[2] 

机构地区：[1]厦门大学物理系,福建厦门361005 [2]中国科学院半导体研究所超晶格国家重点实验室,北京100083

出　　处：《半导体光电》2005年第6期519-522,526,共5页Semiconductor Optoelectronics

摘　　要：采用MBE设备生长了多层InAs/GaAs量子点结构,测量了其变温光致发光谱和时间分辨光致发光谱。结果表明多层量子点结构有利于减小发光峰的半高宽,并且可以提高发光峰半高宽和发光寿命的温度稳定性。实验发现,加InGaAs盖层后,量子点发光峰的半高宽进一步减小,最小达到23.6 meV,并且发光峰出现红移。原因可能在于InGaAs盖层减小了InAs岛所受的应力,阻止了In组分的偏析,提高了InAs量子点尺寸分布的均匀性和质量,导致载流子在不同量子点中的迁移效应减弱。Multilayer InAs/GaAs quantum dots structures were grown by molecular-beam epitaxy （MBE）. The steady-state and time-resolved photoluminescence of the samples were measured at various temperatures. Results showed that multilayer structures could not only narrow the photoluminescence FWHM（full width at the half maximum） but enhance the stability of the photoluminescence lifetime and FWHM. As for the quantum dots with InGaAs cap layer, the photoluminescent spectra became narrower（the narrowest FWHM was only 23. 6 meV） and the photoluminescent wavelength became longer. The possible reason for the above phenomena was that the InGaAs cap layer could both release the strains in InAs islands and inhibit segregation of In components, resulting in the weaker migration among different quantum dots.

关 键 词：多层InAs量子点 光致发光 时间分辨谱 

分 类 号：O472.3[理学—半导体物理]