The role of Ag buffer layer in Fe islands growth on Ge (111) surfaces.

Autor: Tsu-Yi Fu, Jia-Yuan Wu, Ming-Kuan Jhou, Hung-Chan Hsu
Předmět:
Zdroj: Journal of Applied Physics; 2015, Vol. 117 Issue 17, p17B724-1-17B724-4, 4p, 2 Color Photographs, 1 Diagram
Abstrakt: Sub-monolayer iron atoms were deposited at room temperature on Ge (111)-c(2 × 8) substrates with and without Ag buffer layers. The behavior of Fe islands growth was investigated by using scanning tunneling microscope (STM) after different annealing temperatures. STM images show that iron atoms will cause defects and holes on substrates at room temperature. As the annealing temperature rises, iron atoms pull out germanium to form various kinds of alloyed islands. However, the silver layer can protect the Ag/Ge(111)-(√3×√3) reconstruction from forming defects. The phase diagram shows that ring, dot, and triangular defects were only found on Ge (111)-c(2 × 8) substrates. The kinds of islands found in Fe/Ge system are similar to Fe/Ag/Ge system. It indicates that Ge atoms were pulled out to form islands at high annealing temperatures whether there was a Ag layer or not. But a few differences in big pyramidal or strip islands show that the silver layer affects the development of islands by changing the surface symmetry and diffusion coefficient. The structure characters of various islands are also discussed. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index