Anomalous Kinetic Roughening of Nanostructured Ag Islands on Liquid Surfaces

作者:Zhang, Chuhang*; Lv, Neng; Zhu, Yuhong; Zhang, Xiaofei; Ye, Gaoxiang
来源:Journal of the Physical Society of Japan, 2012, 81(3): 034602.
DOI:10.1143/JPSJ.81.034602

摘要

By atomic force microscopy, the surface evolution and kinetic roughening of nanostructured Ag islands on silicone oil surfaces are studied. It is found that the islands are composed of quasi-circular granules with planar size around 50.0 nm, which is approximately independent of nominal thickness d. Our measurement indicates that the geometrical shape of the granules changes from plateau to sphere as d goes up. The dynamic scaling analysis reveal that the roughness exponent alpha varies between 0.80 and 0.90 as d increases. The average roughness w(rms) shows power-law relationship with d and the growth exponent beta = 0.53 +/- 0: 03 when d <= 4.0 nm. However, w(rms) deviates obviously from the power-law relationship for the samples with d > 4: 0 nm. This anomalous behavior of beta is explained by the competition between the shadowing and reemission processes, and then the kinetic evolution and formation mechanism of the islands are presented.