Theoretical and experimental analyses of the deposited silver thin films

Abstract

The silver thin films have been prepared using magnetron DC‐sputtering. We discuss in detail the thin films AFM images and their properties in different sputtering times of 2 to 6 minutes. Despite the low thickness of the films, the roughness saturation amounts, Ws, are well separated. The surface data do not follow the normal Family‐Vicsek scaling, and we have the local growth exponent, β(Ws(t)∼tβ). We obtained the global roughness scaling exponent α=0.36 and growth exponent, β=0.50. We also obtain the fractal spectrum of the data, f(α). The results show that the spectrum is right‐hook like. It distinguishes between different film thicknesses even in small sizes of hundreds of nanometers. Furthermore, we measure the surface conductivities and compare them to the thin film roughnesses. We investigate the roughness and fractality of the AFM data, looking for their relations to width and conductivity of the silver thin film samples.

Fractality and roughness of the ZnO:Cu composite thin films annealed in different temperatures

“…Afterwards, the same procedure was conducted in ethanol and acetone. Finally, all the samples were dried in the presence of nitrogen flow [10].…”

“…Multifractal spectra, f (a) is usually employed to describe multifractality. Here, we used the box-counting method [10,19]. In this method the image is decomposed into boxes of size l × l. The average of the film deposition probability in box (i, j) is called p ij (l):…”

“…Please note that as p ij (l) is a probability distribution we have i,j p ij (l) = 1 over all boxes of size l. Moreover, we have p ij (l) l a ′ and the number of boxes of scaling exponent a ′ should scale as N a ′ l −f (a ′ ) . a ′ is also Lipschitz-Hölder exponent which is the singularity of the subset of probabilities [10,19,21]. N a ′ is the number of boxes of size L with the same Lipschitz-Hölder exponent a ′ .…”

“…From a theoretical point of view, research into the roughness of empirically prepared layers with the help of data obtained from AFM is an interesting topic. In this case, Abdolvahab et al recently showed that silver thin films are characterised by using roughness and multifractal analysis even in small thicknesses of the order of tens of nanometres [10,11].…”

Kinetic Monte Carlo simulation of polycrystalline silver metal electrodeposition: scaling of roughness and effects of deposition parameters

“…It can be concluded that the surface roughness depends strongly on the type of the used electrolyte. On the other hand, it is found that the growth exponent of some physical vapour deposition (PVD) models 68,71 is lower than that of electrodeposition models due to the medium and conditions of thin film deposition. As shown in Table 2, in the study of silver nanoparticle deposition at an argon gas pressure of 30 Pa, the growth exponent b is found to be 0.27.…”