Growth of silver on zinc oxide via lattice and off-lattice adaptive kinetic Monte Carlo

Abstract

The growth of Ag on ZnO was modeled using a reactive force field potential and a combination of molecular dynamics and adaptive kinetic Monte Carlo (AKMC) simulations. An adaptive lattice-based AKMC model is described as a method of extending timescales and length scales that can be simulated. Reusing previously found transitions to reduce computational time is discussed for both the lattice and off-lattice AKMC approaches. With these methods, growth of over 1 monolayer's worth of Ag is simulated corresponding to a real deposition time of up to 0.1 s. The results show that the deposited silver aggregates on the surface through mainly single atom moves with few concerted motions. Initially silver adatoms do not agglomerate and the energy barriers for silver dimers to form are larger than for them to break apart. The first layer of silver grows as a series of connected regions rather than forming well-defined centro-symmetric islands.

Ultrathin sputter-deposited plasmonic silver nanostructures

“…The reported large diffusivity of Ag on various weakly interacting substrates supports this argument. 46,47 In any case, it seems that the silver growth on AZO is improved by the presence of the structure, making stable nanostructured Ag lms as thin as 6 nm possible. The formation of Ag grains on the side walls of the nanostructures was further investigated by change of the geometry of the nanostructured resist, prior to deposition of 10 nm AZO and 6 nm Ag.…”

Modelling thin film growth in the Ag–Ti system

“…Super-basins are built on-the-fly by exploring all states connected by lowbarrier transitions and then removing these transitions from the KMC event table allowing only the escaping transitions to be included -hence accelerating the simulation time. The super-basin method implemented in our code is an extension of the on-lattice method described in [2] and the off-lattice method further described in [29] where local basins are built from defect volumes, rather than including the whole system. This allows multiple basins to exist simultaneously.…”

“…To optimise the coatings requires a knowledge of how the different materials grow. One such interface considered by our group, [2] involved modelling Ag growth on a ZnO substrate. This showed that the Ag atoms would cover the ZnO surface before growing in islands under normal operating conditions.…”

“…For example using temperature accelerated dynamics, Sprague et al [14] have shown that different growth patterns can occur when growing Cu on Ag if MD alone is used. In this paper we investigate the initial phases of growth of Ti on both Ag (100) and (111) surfaces and also consider Ag growth on Ti using a hybrid MD and adaptive KMC [15,16] approach that has been used successfully by our group on other systems such as Ag growth on Ag [17] and Ag on ZnO [2].…”

Coarse‐grained approach to amorphous and anisotropic materials in kinetic Monte Carlo thin‐film growth simulations: A case study of TiO2and ZnO by plasma‐enhanced chemical vapor deposition

“…The major aim is to provide straightforward paths in the experimental routes toward the optimization of the properties and final performance in the targeted applications. Depending on the scale and nature of the features to be studied, the simulations usually range from those based on molecular dynamics (MD), [1,2] kinetic Monte Carlo (KMC), [3,4] or hybrid methods [5][6][7][8] to continuum methods. [9][10][11][12] There is a wide range of technological applications for which the growth of thin films in multilayer systems (or even in more complex nanostructures) is a fundamental part.…”