Characteristic Length of Metallic Nanorods under Physical Vapor Deposition

By using physical vapor deposition (PVD) to grow metallic nanorods, the characteristic length is controllable, which can be identified by two different growth modes: Mode I and Mode II. In Mode I, the growth of metallic nanorods is dominated by the monolayer surface steps. Whereas in Mode II, the growth mechanism is mainly determined by the multilayer surface steps. In this work, we focused on the analysis of the physical process of Mode I, in which the adatoms diffuse on the monolayer surface at beginning, then diffuse down to the next monolayer surface, and finally result in the metallic nanorods growth. Based on the physical process, both the variations of the characteristic length and the numerical solutions were theoretically proposed. In addition, the two-dimensional (2D) lattice kinetic Monte Carlo simulations were employed to verify the theoretical derivation of the metallic nanorods growth. Our results pay a new way for modifying the performance of metallic nanorods-based applications and devices.