Uniform formation of high-density InAs quantum dots by InGaAs capping growth

作者：Tonomura Shinichi; Yamaguchi Koichi^*

来源：Journal of Applied Physics, 2008, 104(5): 054909.

DOI：10.1063/1.2975366

We studied the capping growth process of an InGaAs on high-density InAs/GaAs(001) quantum dots (QDs) with a bimodal size distribution grown by molecular beam epitaxy. Atomic force microscopy and reflection high energy electron beam diffraction observations revealed that the bimodal size distribution is composed of larger QDs with {110} facets and smaller QDs with {136} facets. In addition, it was found that, during the InGaAs capping growth, the height of larger QDs decreased, while the height of smaller QDs increased due to the incorporation of indium adatoms. As a result, the size fluctuation of the QDs was suppressed as compared to GaAs capping growth. We achieved a narrow photoluminescence (PL) linewidth of 24 meV and an enhanced PL peak intensity.

• 出版日期2008-9-1