Ga induced 2D superstructural phase diagram on trenched Si(5 5 12) surface

详细信息	查看全文 | 推荐本文 |

• 作者：Praveen Kumar^a ; Mahesh Kumar^b ; S.M. Shivaprasad^a ; ^{smsprasad@jncasr.ac.in}
• 关键词：Ga ; Nanowire ; Nanochain ; Phase diagram
• 刊名：Surface Science
• 出版年：2012
• 期刊代码：104_00396028
• 类别：ch
• 出版时间：July, 2012
• 卷：606
• 期：13-14
• 页码：1045-1049
• 文件大小：782 K

摘要

The high index Si(5 5 12) surface offers morphological trenches, which can be interesting for epitaxial growth. In this study, the evolution of Ga adsorption at a very low flux rate of 0.03 ML/min on high index trenched Si(5 5 12) 鈭?#xA0;2 脳 1 reconstructed surface at various substrate temperatures ranging from room temperature (RT) to 600 掳C has been investigated using in-situ AES, LEED and EELS. The Auger uptake curves, which plot the Ga(LMM)/Si(LVV) Auger intensity ratio with Ga adsorption time, show that Ga grows in layer plus islands mode for substrate temperatures in the RT to 350 掳C range, while it grows in Volmer-Weber (3D islands) for higher substrate temperatures (> 350 掳C). We also arrive at a complete 2D superstructural phase diagram for Ga/Si(5 5 12) interfacial system that shows the pathways to attain the different superstructural phases. The formation of Ga nanowires as (2 2 5), (3 3 7) phase and Ga 3D islands in the (1 1 2) 鈭?#xA0;6 脳 1, (1 1 2) 鈭?#xA0;6 脳 2 phases and other Ga induced superstructural phases like (7 7 17) + 2x(1 1 3), (2 2 5) + (3 3 7), 1 脳 1 has been carefully followed. The electronic structures of each of the observed phases have been probed by EELS and each of them is shown to have characteristic features.