Underlying strain-induced growth of the self-assembled Ge quantum-dots prepared by ion beam sputtering deposition

作者：Yang Jie^*; Wang Chong; Jin Ying-Xia; Li Liang; Tao Dong-ping; Yang Yu

来源：Acta Physica Sinica, 2012, 61(1): 016804.

• Ge quantum dots
• strain
• ion beam sputtering

The quantum-dot samples with single Ge layer and twofold stacked Ge layers are prepared by ion beam sputtering deposition. The different sizes and morphologies of quantum-dots are characterized using atomic force microscope technique. The effects of strain from the capped Ge quantum-dots on the upper Ge wetting layer and the nucleation are also investigated by the buried strain model. The results show that the non-uniform strain in the Si spacing layer which caps the buried quantum-dot layer, leads to the decrease of Ge critical thickness in the upper layer, which increases the upper dot size. The strain intensity increases with the decrease of Si spacer thickness, which results in the changes of dot shape and size in the upper layer. Furthermore, the strain also modulates the distribution of upper quantum-dot layer.

• 出版日期2012-1
• 单位云南大学; 昆明理工大学