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报道了利用分子束外延技术在（001）GaAs衬底上生长的单层及多层InAs量子点材料的透射电子显微镜（TEM）研究结果，并对量子点的结构特性进行了讨论．结果表明：多层量子点呈现明显的垂直成串排列趋势；随着InAs量子点层数的增加，量子点的密度下降，其尺寸随层数的增加趋向均匀．在试验条件下，5层量子点材料的InAs量子点厚度和GaAs隔离层的厚度的选择都比较合理，其生长过程中的应变场更有利于自组织量子的形成．
The results of transmission electron microscopy (TEM) studies of single and multi-layer InAs quantum dots grown on (001) GaAs substrate by molecular beam epitaxy are reported, and the structural characteristics of QDs are discussed. The results show that the multi-layer quantum dots show a remarkable vertical string-like arrangement. As the number of InAs quantum dots increases, the density of quantum dots decreases and its size tends to be uniform with the increase of the number of layers. Under the experimental conditions, the thickness of InAs quantum dots and the thickness of GaAs isolation layer in five layers of quantum dot material are all reasonable, and the strain field in the growth process is more conducive to the formation of self-organized quantum.