Leaky atomic traps: Upward diffusion of Au from nanoscale pits on ionic-crystal surfaces

作     者：M. Goryl F. Buatier de Mongeot F. Krok A. Vevecka-Priftaj M. Szymonski 

作者机构：Center for Nanometer-Scale Science and Advanced Materials (NANOSAM) Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University ulica Reymonta 4 30-059 Krakow Poland Dipartimento di Fisica Università di Genova Via Dodecaneso 33 16146 Genova Italy Department of Physics Polytechnic University of Tirana Sheshi “Nene Tereza” No. 4 Tirana Albania 

出 版 物：《Physical Review B》 (Phys. Rev. B Condens. Matter Mater. Phys.)

年 卷 期：2007年第76卷第7期

页      面：075423-075423页

核心收录：

学科分类：0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

摘      要：We have investigated the formation of gold nanoclusters during submonolayer deposition on atomically flat KBr and RbI (001) ionic-crystal substrates, as well as on substrates patterned with two-dimensional (2D) nanoscale pits produced by electron stimulated desorption. In this way, it is possible to produce atomic steps free from stress and local charging, which are normally considered the reason for enhanced cluster nucleation. Easy nucleation of the Au clusters inside the pits at the lower side of the atomic step edge is not observed, while nucleation of the Au nanoclusters is found to occur preferentially at the upper step edges. Moreover, we observe that gold atoms landing inside the bottom of the pits are able to escape from them by means of thermally activated upward diffusion at the step edges. We propose that the preferential Au nucleation sites at the edges of 2D pits are activated by F centers produced in electronic processes used for nanopatterning of the ionic crystals.