Thin film deposition with time-varying temperature

Assis, Thiago A. de; Reis, F. D. A. Aarão

doi:10.1088/1742-5468/2013/10/p10008

Cited by 7 publications

(5 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results for small R (100 or less) and small thicknesses (1000 monolayers or less) show features of anomalous roughening, i. e. the log w × log r curves for different times are split for small r. This was already observed for ǫ = 0 in Ref. [33]. For R ≥ 10 3 , the curves for short times are also split, but coincide after ≈ 100 monolayers.…”

Section: Local Roughness Scalingsupporting

confidence: 65%

Dynamic scaling and temperature effects in thin film roughening

Assis¹,

Reis²

2015

J. Stat. Mech.

Self Cite

View full text Add to dashboard Cite

The dynamic scaling of mesoscopically thick films (up to 10 4 atomic layers) grown with the Clarke-Vvedensky model is investigated numerically for broad ranges of values of the diffusion-to-deposition ratio R and lateral neighbor detachment probability ǫ, but with no barrier at step edges. The global roughness scales with the film thickness t as W ∼ t β / R 3/2 (ǫ + a) , where β ≈ 0.2 is the growth exponent consistent with Villain-Lai-Das Sarma (VLDS) scaling and a = 0.025. This general dependence on R and ǫ is inferred from renormalization studies and shows a remarkable effect of the former but a small effect of the latter, for ǫ ≤ 0.1. For R ≥ 10 4 , very smooth surfaces are always produced. The local roughness shows apparent anomalous scaling for very low temperatures (R ≤ 10 2 ), which is a consequence of large scaling corrections to asymptotic normal scaling. The scaling variable R 3/2 (ǫ + a) also represents the temperature effects in the scaling of the correlation length and appears in the dynamic scaling relation of the local roughness, which gives dynamic exponent z ≈ 3.3 also consistent with the VLDS class.

show abstract

Section: Local Roughness Scalingsupporting

confidence: 65%

Dynamic scaling and temperature effects in thin film roughening

Assis¹,

Reis²

2015

J. Stat. Mech.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Note that each sample simulated here is grown at a constant temperature, which is the most usual condition in experiments. Significantly different results are observed if the temperature changes during the growth of a film, possibly including apparent anomalous roughening [45]; however, this case is not considered here.…”

Section: Discussionmentioning

confidence: 92%

Temperature Effects in the Initial Stages of Heteroepitaxial Film Growth

Reis

2022

Surfaces

View full text Add to dashboard Cite

Kinetic Monte Carlo simulations of a model of thin film heteroepitaxy are performed to investigate the effects of the deposition temperature in the initial growth stages. Broad ranges of the rates of surface processes are used to model materials with several activation energies and several temperature changes, in conditions of larger diffusivity on the substrate in comparison with other film layers. When films with the same coverage are compared, the roughness increases with the deposition temperature in the regimes of island growth, coalescence, and initial formation of the continuous films. Concomitantly, the position of the minimum of the autocorrelation function is displaced to larger sizes. These apparently universal trends are consequences of the formation of wider and taller islands, and are observed with or without Ehrlich-Schwöebel barriers for adatom diffusion at step edges. The roughness increase with temperature qualitatively matches the observations of recent works on the deposition of inorganic and organic materials. In thicker films, simulations with some parameter sets show the decrease of roughness with temperature. In these cases, a re-entrance of roughness may be observed in the initial formation of the continuous films.

show abstract

“…However, the scaling of the local roughness at short scales does not provide estimates of the roughness exponent in agreement with the universality classes they belong for several irreversible growth models in both oneand two-dimensional substrates [22]. This caveat was also observed for the CV model in both irreversible [23] and reversible [19] aggregation versions. Then, a direct measurement of the roughness exponent corresponding to CV model is still lacking.…”

Section: Introductionmentioning

confidence: 78%

Optimal detrended fluctuation analysis as a tool for the determination of the roughness exponent of the mounded surfaces

2017

View full text Add to dashboard Cite

We present an optimal detrended fluctuation analysis (DFA) and applied it to evaluate the local roughness exponent in non-equilibrium surface growth models with mounded morphology. Our method consists in analyzing the height fluctuations computing the shortest distance of each point of the profile to a detrending curved that fits the surface within the investigated interval. We compare the optimal DFA (ODFA) with both the standard DFA and nondetrended analysis. We validate the ODFA method considering a one-dimensional model in the Kardar-Parisi-Zhang universality class starting from a mounded initial condition. We applied the methods to the Clarke-Vvdensky (CV) model in 2 + 1 dimensions with thermally activated surface diffusion and absence of step barriers. It is expected that this model belongs to the nonlinear Molecular Beam Epitaxy (nMBE) universality class. However, an explicit observation of the roughness exponent in agreement with the nMBE class was still missing. The effective roughness exponent obtained with ODFA agrees with the value expected for nMBE class whereas using the other methods it does not. We also characterized the transient anomalous scaling of the CV model and obtained that the corresponding exponent is in agreement with the value reported for other nMBE models with weaker corrections to the scaling.

show abstract

Thin film deposition with time-varying temperature

Cited by 7 publications

References 54 publications

Dynamic scaling and temperature effects in thin film roughening

Dynamic scaling and temperature effects in thin film roughening

Temperature Effects in the Initial Stages of Heteroepitaxial Film Growth

Optimal detrended fluctuation analysis as a tool for the determination of the roughness exponent of the mounded surfaces

Contact Info

Product

Resources

About