Choi Ilgyu, Lee Hyunjoong, Lee Cheul-Ro, Jeong Kwang-Un, Kim Jin Soo
Department of Electronic and Information Materials Engineering, Division of Advanced Materials Engineering, and Research Center of Advanced Materials Development (RCAMD), Chonbuk National University, Jeonju 54896, Republic of Korea.
Nanotechnology. 2018 Aug 3;29(31):315603. doi: 10.1088/1361-6528/aac414. Epub 2018 May 11.
This paper reports the formation of GaN and InN quantum dots (QDs) with symmetric spherical shapes, grown on SiN/Si(111). Spherical QDs are grown by modulating initial growth behavior via gallium and indium droplets functioning as nucleation sites for QDs. Field-emission scanning electron microscope (FE-SEM) images show that GaN and InN QDs are formed on curved SiN/Si(111) instead of on a flat surface similar to balls on a latex mattress. This is considerably different from the structural properties of In(Ga)As QDs grown on GaAs or InP. In addition, considering the shape of the other III-V semiconductor QDs, the QDs in this study are very close to the ideal shape of zero-dimensional nanostructures. Transmission-electron microscope images show the formation of symmetric GaN and InN QDs with a round shape, agreeing well with the FE-SEM results. Compared to other III-V semiconductor QDs, the unique structural properties of Si-based GaN and InN QDs are strongly related to the modulation in the initial nucleation characteristics due to the presence of droplets, the degree of lattice mismatch between GaN or InN and SiN/Si(111), and the melt-back etching phenomenon.
本文报道了在SiN/Si(111)上生长的具有对称球形形状的氮化镓（GaN）和氮化铟（InN）量子点（QD）的形成情况。球形量子点是通过镓和铟液滴作为量子点的成核位点来调节初始生长行为而生长的。场发射扫描电子显微镜（FE-SEM）图像显示，GaN和InN量子点形成于弯曲的SiN/Si(111)上，而不是类似于乳胶床垫上的球那样形成于平坦表面。这与在砷化镓（GaAs）或磷化铟（InP）上生长的铟镓砷（In(Ga)As）量子点的结构特性有很大不同。此外，考虑到其他III-V族半导体量子点的形状，本研究中的量子点非常接近零维纳米结构的理想形状。透射电子显微镜图像显示形成了具有圆形的对称GaN和InN量子点，与FE-SEM结果吻合良好。与其他III-V族半导体量子点相比，基于硅的GaN和InN量子点的独特结构特性与由于液滴的存在导致的初始成核特性调制、GaN或InN与SiN/Si(111)之间的晶格失配程度以及回熔蚀刻现象密切相关。
