A brief review of mathematical models of thin film growth and surfaces

Abstract

The morphology of thin films has been extensively studied in the last years. The properties of a thin film are closely related to its microstructure, especially to its morphology and surface roughness. Optical reflectivity, conductivity, and porosity are characteristics that depend on the film structure. The knowledge of atomistic details of the thin film growth process is useful for the development of new techniques and the control of thin films and new materials. Models of growth process are very powerful tools that can help researchers to predict and control physical, chemical, and mechanical properties. In this work we briefly summarize the theoretical models that have been used in the studies of thin films growth. By describing the deposition process of atoms/molecules on the surface of the substrate, one can study the evolution of the bulk and the surface roughness of a thin film. If an experimental growth process is appropriately described by a theoretical model (or even a combination of one or more different models), it can also provide indications to control the surface roughness and porosity of the film. Controlling the growth process one can obtain materials with a set of desired properties, namely tribological, porosity, and electrical ones. These characteristics are necessary for example, for hosting a solid lubricant on the surface of the material. We believe that the models presented in this work can be very useful in understanding the mechanisms of control and adherence of electrodeposited films which are commonly used in medical applications such as stent devices. We also believe that the models can be helpful to the understanding surface problems related to the superficial defects in stents.

On Ballistic Deposition Process on a Strip

“…The BD models date back to [57] and [54], where a variation of the model was proposed to describe sedimentation and aggregation in colloids. Models of this type have been applied to study formation, morphology, and surface roughness of sedimentary rocks [22] and thin films [21, 34].…”

Atomic-scale investigation of MgO growth on fused quartz using angle-dependent NEXAFS measurements

“…[1][2][3] Based on various approaches, mathematical models developed for the determination of lm growth were illustrated by Forgerini and Marchiori (2014). 4 The microstructural evolution of lm growth is governed by number of different processes, such as nucleation, coalescence, competitive grain growth, and recrystallization. 5 In addition to these processes, it is reported that processes like adsorption and surface reaction not only promote lm growth but also inuence the surface properties of thin lms.…”

Theoretical and experimental studies of ternary and quaternary nitrides for machining and thermoelectric materials

“…Crystal growth or island growth is when individual dispersed crystals grow from many nuclei, but when this occurs the final orientation is not always determined. This can later be changed, when it grows as part of a polycrystalline structure and there is for the collective behavior of the polycrystalline film a dependence of for instance grain size and surface conditions [41,44].…”