Nano-sculptured thin film thickness variation with incidence angle

We present a new network modeling approach for various thin film growth techniques that incorporates re-emitted particles due to the non-unity sticking coefficients. We model re-emission of a particle from one surface site to another one as a network link, and generate a network model corresponding to the thin film growth. Monte Carlo simulations are used to grow films and dynamically track the trajectories of re-emitted particles. We performed simulations for normal incidenc...

Strain engineering is the art of inducing controlled lattice distortions in a material to modify specific physicochemical properties. Strain engineering is applied for basic fundamental studies of physics and chemistry of solids but also for device fabrication through the development of materials with new functionalities. Thin films are one of the most important tools for strain engineering. Thin films can in fact develop large strain due to the crystalline constrains at the ...

Diffraction of light beams from the phase steps due to the abrupt changes in the boundary of step leads to Fresnel fringes that their visibility and intensity profile depend on the change of the step height or light incident angle. The visibility has been utilized in measurements of different physical quantities. In this paper, for the first time to our knowledge, by introducing the fitting method as a fast method we show that by fitting the theoretical intensity distribution...

We propose a numerical tool to mimic the pulsed deposition of nanoparticles, a technique used to fabricate thin films from the deposition of nanoparticles upon a substrate. We employ such tool under different initial conditions, in particular exploring the effect of depositing an heterogeneous/homogenenous sample of nanoparticles in terms of their morphology (size and shape). We monitor how changing the nature of the building block affects the porosity and roughness of the gr...

In this paper, we introduce a novel artificial neural network (ANN) based scheme to estimate the thickness of thin films deposited on a given substrate. Here we consider the visible interference pattern between a plane wave and a diverging wave reflected from the thin film surface that records the thickness information of the thin film. We assume a uniform thickness profile of the film. However, the thickness increases as the deposition takes place. We extract the intensity d...

In this paper we present a generalization of a simple solid-on-solid epitaxial model of thin films growth, when surface morphology anisotropy is provoked by anisotropy in model control parameters: binding energy and/or diffusion barrier. The anisotropy is discussed in terms of the height-height correlation function. It was experimentally confirmed that the difference in diffusion barriers yields anisotropy in morphology of the surface. We got antisymmetric correlations in the...

We propose a model for predicting the fluctuations of electron states in thin films as function of film thickness. The model was derived based on the assumption of the existence of potential barrier fluctuations on the film surface. Since the wave functions of electrons in the film is determined by the boundary conditions of potential on the film surface, potential fluctuations on the film surface implies the fluctuations of electron states in the film. The model was then ext...

We report on the investigation of height distributions (HDs) and spatial covariances of two-dimensional surfaces obtained from extensive numerical simulations of the celebrated Clarke-Vvedensky (CV) model for homoepitaxial thin film growth. In this model, the effect of temperature, deposition flux, and strengths of atom-atom interactions are encoded in two parameters: the diffusion to deposition ratio $R=D/F$ and $\varepsilon$, which is related to the probability of an adatom...

The high inertia of classical fluid coating processes severely limits the possibility of controlling the deposited film thickness through the entrainment velocity. We describe and characterize a new experimental device where the inertia is dramatically reduced, allowing for millimeter-scale patterning with micrometer-accurate thickness. Measuring precise film profiles over large spatial extents with high temporal resolution poses a challenge, which we overcome using a custom ...

We showed that a wetting layer in epitaxially strained thin films which decreases with increasing lattice mismatch strain arises due to the variation of nonlinear elastic free energy with film thickness. We calculated how and at what thickness a flat film becomes unstable to perturbations of varying size for films with both isotropic and anisotropic surface tension. We showed that anisotropic surface tension gives rise to a metastable enlarged wetting layer. The perturbation ...