The epitaxial growth and unique morphology of InAs quantum dots embedded in a Ge matrix
The epitaxial growth and unique morphology of InAs quantum dots embedded in a Ge matrix
复制标题
DOI：
10.1088/1361-6463/ac95a3
复制
发表时间：
2022-12-08
影响因子：
3.4
通讯作者：
Liu，Huiyun
中科院分区：
文献类型：
--
作者：
Jia，Hui;Yang，Junjie;Liu，Huiyun
在这项工作中，我们研究了在Ge衬底上外延生长InAs量子点。通过改变生长温度、沉积厚度和InAs的生长速率等生长参数，利用固体源分子束外延技术在Ge衬底上成功地外延生长了高密度（1.2× 1011 cm− 2）的InAs量子点，并在量子点上覆盖Ge层。发现了镶嵌在Ge基质中的金字塔和多面体形状的InAs量子点，这与InAs/GaAs或InAs/Si系统中的透镜形或截短的椭圆形量子点不同。此外，与200 nm的Ge盖层，三分之一的嵌入式量子点被发现与尺寸为7-9 nm的椭圆形和六边形的纳米空隙，据我们所知，这是第一次观察到的InAs量子点嵌入在Ge矩阵。这些结果提供了一个新的可能性，集成在IV族硅光子学平台上的量子点器件。
In this work, we investigate the epitaxial growth of InAs quantum dots (QDs) on Ge substrates. By varying the growth parameters of growth temperature, deposition thickness and the growth rate of InAs, high density (1.2× 10 11 cm− 2) self-assembled InAs QDs were successfully epitaxially grown on Ge substrates by solid-source molecular beam epitaxy and capped by Ge layers. Pyramid-and polyhedral-shaped InAs QDs embedded in Ge matrices were revealed, which are distinct from the lens-or truncated pyramid-shaped dots in InAs/GaAs or InAs/Si systems. Moreover, with a 200 nm Ge capping layer, one-third of the embedded QDs are found with elliptical and hexagonal nanovoids with sizes of 7–9 nm, which, to the best of our knowledge, is observed for the first time for InAs QDs embedded in a Ge matrix. These results provide a new possibility of integrating InAs QD devices on group-IV platforms for Si photonics.