scholarly journals A Parametric Three-Dimensional Phase-Field Study of the Physical Vapor Deposition Process of Metal Thin Films Aiming at Quantitative Simulations

Coatings ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 607 ◽  
Author(s):  
Shenglan Yang ◽  
Jing Zhong ◽  
Miao Chen ◽  
Lijun Zhang
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Deposition Rate ◽  
Phase Field ◽  
Physical Vapor Deposition ◽  
Three Dimensional ◽  
Quantitative Relationship ◽  
Deposition Process ◽  
Model Parameters ◽  
Metal Thin Films

In this paper, a parametric three-dimensional (3D) phase-field study of the physical vapor deposition process of metal thin films was performed aiming at quantitative simulations. The effect of deposition rate and model parameters on the microstructure of deposited thin films was investigated based on more than 200 sets of 3D phase-field simulations, and a quantitative relationship between the deposition rate and model parameters was established. After that, the heat maps corresponding to the experimental atomic force microscopy images were plotted for characterization of the surface roughness. Different roughness parameters including the arithmetic average roughness (Ra), root mean square roughness (Rq), skewness (Rsk), and kurtosis (Rku), as well as the ratio of Rq to Ra were calculated and carefully analyzed. A quantitative relationship between the surface roughness and the deposition rate and model parameters was obtained. Moreover, the calculated Rq to Ra ratios for the thin films at the deposition rates of 0.22 and 1.0 nm s−1 agreed very well with the experimental data of the deposited Mo and Ti thin films. Finally, further discussion about the correlative behaviors between the surface roughness and the density was proposed for reasoning the shadowing effect as well as the formation of voids during the thin film production.

scholarly journals Surface roughness minimum: Ag thin layer deposited on a glass

2001 ◽  
Vol 66 (7) ◽  
pp. 483-490 ◽  
Author(s):  
R. Petrovic ◽  
S. Strbac ◽  
N. Bundaleski ◽  
Z. Rakocevic
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Thin Layer ◽  
Layer Thickness ◽  
Deposition Rate ◽  
Turning Point ◽  
Deposition Time ◽  
Substrate Surface ◽  
Deposition Process ◽  
Silver Thin Films

In this paper the results of an examination of the surface roughness and morphology dependence of silver thin films up to 100 nm thick deposited on a microscope glass on the deposition rate and on the deposition time are presented. It was found that, for a constant deposition rate, the surface roughness exhibits minimum at a certain layer thickness. This coincides with the turning point when the influence of the substrate surface on the deposition process becomes negligible, i.e., to the change in the nature of the system substrate/deposit from Ag/glass to Ag/Ag. For a constant layer thickness, sthe surface roughness minimum, achieved at a certain deposition rate, coincides to the turning point when the average free path for vertical adatom mobility becomes zero.

scholarly journals Modeling the Layer-by-Layer Growth of HKUST-1 Metal-Organic Framework Thin Films

Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1631
Author(s):  
Qiang Zhang ◽  
Yohanes Pramudya ◽  
Wolfgang Wenzel ◽  
Christof Wöll
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Deposition Rate ◽  
Layer Growth ◽  
Coarse Grained ◽  
Structural Defects ◽  
Effect Of Temperature ◽  
Layer By Layer ◽  
Reactant Concentration ◽  
Metal Organic

Metal organic frameworks have emerged as an important new class of materials with many applications, such as sensing, gas separation, drug delivery. In many cases, their performance is limited by structural defects, including vacancies and domain boundaries. In the case of MOF thin films, surface roughness can also have a pronounced influence on MOF-based device properties. Presently, there is little systematic knowledge about optimal growth conditions with regard to optimal morphologies for specific applications. In this work, we simulate the layer-by-layer (LbL) growth of the HKUST-1 MOF as a function of temperature and reactant concentration using a coarse-grained model that permits detailed insights into the growth mechanism. This model helps to understand the morphological features of HKUST-1 grown under different conditions and can be used to predict and optimize the temperature for the purpose of controlling the crystal quality and yield. It was found that reactant concentration affects the mass deposition rate, while its effect on the crystallinity of the generated HKUST-1 film is less pronounced. In addition, the effect of temperature on the surface roughness of the film can be divided into three regimes. Temperatures in the range from 10 to 129 °C allow better control of surface roughness and film thickness, while film growth in the range of 129 to 182 °C is characterized by a lower mass deposition rate per cycle and rougher surfaces. Finally, for T larger than 182 °C, the film grows slower, but in a smooth fashion. Furthermore, the potential effect of temperature on the crystallinity of LbL-grown HKUST-1 was quantified. To obtain high crystallinity, the operating temperature should preferably not exceed 57 °C, with an optimum around 28 °C, which agrees with experimental observations.

Effect Of Phosphorus On Ge/Si(001) Island Formation

2002 ◽  
Vol 737 ◽  
Author(s):  
Theodore I. Kamins ◽  
Gilberto Medeiros-Ribeiro ◽  
Douglas A. A. Ohlberg ◽  
R. Stanley Williams
Keyword(s):  
Deposition Rate ◽  
Strain Energy ◽  
Competitive Adsorption ◽  
Lattice Mismatch ◽  
Three Dimensional ◽  
Deposition Process ◽  
Thin Layers ◽  
Island Size ◽  
Partial Pressures ◽  
Intermediate Size

ABSTRACTWhen Ge is deposited epitaxially on Si, the strain energy from the lattice mismatch causes the Ge in layers thicker than about four monolayers to form distinctive, three-dimensional islands. The shape of the islands is determined by the energies of the surface facets, facet edges, and interfaces. When phosphorus is added during the deposition, the surface energies change, modifying the island shapes and sizes, as well as the deposition process. When phosphine is introduced to the germane/hydrogen ambient during Ge deposition, the deposition rate decreases because of competitive adsorption. The steady-state deposition rate is not reached for thin layers. The deposited, doped layers contain three different island shapes, as do undoped layers; however, the island size for each shape is smaller for the doped layers than for the corresponding undoped layers. The intermediate-size islands are the most significant; the intermediate-size doped islands are of the same family as the undoped, multifaceted “dome” structures, but are considerably smaller. The largest doped islands appear to be related to the defective “superdomes” discussed for undoped islands. The distribution between the different island shapes depends on the phosphine partial pressure. At higher partial pressures, the smaller structures are absent. Phosphorus appears to act as a mild surfactant, suppressing small islands.

scholarly journals Manipulation and Applications of Hotspots in Nanostructured Surfaces and Thin Films

Nanomaterials ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1667 ◽  
Author(s):  
Xiaoyu Zhao ◽  
Jiahong Wen ◽  
Aonan Zhu ◽  
Mingyu Cheng ◽  
Qi Zhu ◽  
...  
Keyword(s):  
Thin Films ◽  
Physical Vapor Deposition ◽  
Molecular Spectroscopy ◽  
Deposition Process ◽  
Etching Time ◽  
Nanostructured Surfaces ◽  
Surface Enhanced ◽  
Surface Enhanced Raman ◽  
Potential Applications ◽  
Enhanced Raman Scattering

The synthesis of nanostructured surfaces and thin films has potential applications in the field of plasmonics, including plasmon sensors, plasmon-enhanced molecular spectroscopy (PEMS), plasmon-mediated chemical reactions (PMCRs), and so on. In this article, we review various nanostructured surfaces and thin films obtained by the combination of nanosphere lithography (NSL) and physical vapor deposition. Plasmonic nanostructured surfaces and thin films can be fabricated by controlling the deposition process, etching time, transfer, fabrication routes, and their combination steps, which manipulate the formation, distribution, and evolution of hotspots. Based on these hotspots, PEMS and PMCRs can be achieved. This is especially significant for the early diagnosis of hepatocellular carcinoma (HCC) based on surface-enhanced Raman scattering (SERS) and controlling the growth locations of Ag nanoparticles (AgNPs) in nanostructured surfaces and thin films, which is expected to enhance the optical and sensing performance.

Dislocation Nucleation and Propagation During Deposition of Cubic Metal Thin Films

2001 ◽  
Vol 677 ◽  
Author(s):  
W. C. Liu ◽  
Y. X. Wang ◽  
C. H. Woo ◽  
Hanchen Huang
Keyword(s):  
Thin Films ◽  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
Three Dimensional ◽  
Thin Film Deposition ◽  
Dislocation Nucleation ◽  
Film Deposition ◽  
Film Material ◽  
Metal Thin Films ◽  
Dynamics Simulations

ABSTRACTIn this paper we present three-dimensional molecular dynamics simulations of dislocation nucleation and propagation during thin film deposition. Aiming to identify mechanisms of dislocation nucleation in polycrystalline thin films, we choose the film material to be the same as the substrate – which is stressed. Tungsten and aluminum are taken as representatives of BCC and FCC metals, respectively, in the molecular dynamics simulations. Our studies show that both glissile and sessile dislocations are nucleated during the deposition, and surface steps are preferential nucleation sites of dislocations. Further, the results indicate that dislocations nucleated on slip systems with large Schmid factors more likely survive and propagate into the film. When a glissile dislocation is nucleated, it propagates much faster horizontally than vertically into the film. The mechanisms and criteria of dislocation nucleation are essential to the implementation of the atomistic simulator ADEPT.

A NEMD Study of the Thermal Conductivity and Surface Roughness of Silicon Thin Films

2008 ◽  
Author(s):  
Tai-Ming Chang ◽  
Chien-Chou Weng ◽  
Mei-Jiau Huang
Keyword(s):  
Thin Films ◽  
Thermal Conductivity ◽  
Surface Roughness ◽  
Surface Potential ◽  
Specular Reflection ◽  
Constant Heat Flux ◽  
Nonequilibrium Molecular Dynamics ◽  
Model Parameters ◽  
Silicon Thin Films ◽  
Three Body

The nonequilibrium molecular dynamics (NEMD) approach is adopted in this work to calculate the in-plane lattice thermal conductivity of Silicon thin films. In the simulation, the Stillinger-Weber (SW) potential is employed to capture both two-body and three-body interactions. The periodic boundary conditions are applied in the in-plane directions of a thin film. An additional surface potential is added to atoms that are near the surfaces. This surface potential imposes a force normal to the plane to prevent atoms from evaporation. A constant heat flux is generated by injecting energy into the system somewhere and withdrawing energy somewhere else via the velocity rescaling method. After a sufficiently long simulation time, the time-averaged temperature distribution is calculated and then the thermal conductivity can be obtained by the Fourier’s law. When the average temperature of the system is lower than the Debye temperature (θD = 645 K for Si), quantum corrections to both the MD temperature and the thermal conductivity are carried out. To speed up the computation, the present MD tool is parallelized based on a spatial decomposition technique. In this study, we attempt to investigate the relationship among the model parameters of the surface potential, the surface roughness, and the specular reflection fraction at the boundary that is often used in many theoretical studies.

TI-X Alloy Composition Modulated Layered Structures

1986 ◽  
Vol 77 ◽  
Author(s):  
A. F. Jankowski ◽  
R. O. Adams ◽  
L. Williams
Keyword(s):  
Thin Films ◽  
Magnetron Sputtering ◽  
Physical Vapor Deposition ◽  
Deposition Process ◽  
Beta Phase ◽  
Layered Structures ◽  
X Ray Diffraction ◽  
Alumina Crucible ◽  
Alloy Series

ABSTRACTThe binary alloy series of Ti-X metallic, composition modulated layered structures has been fabricated via magnetron sputtering. The Ti-X systems (where X is Ta, Mo, or V) explored are exemplary of solid solution systems, such as the supermodulus systems of Cu-Ni, Ag-Pd, Au-Ni, and Cu-Pd (which all feature fee crystalline compatibility). In the present case, the beta-phase of Ti sought in these Ti-X systems suggests bec crystalline compatibility, with interlayer misfit strains not exceeding 10%.The Ti-X series examined, matches elements of high and low atomic number. (Z of Ti, V, Mo, and Ta are 22, 23, 42, and 73, respectively.) Difficulties which arise in a conventional tungsten basket - alumina crucible physical vapor deposition process, i.e. obtaining thr vaporization temperatures for Ti, V, Mo and Ta of 1235, 1332, 1822, and 2240 °C at 130 mPa, respectively, are overcome by magnetron sputtering. Thin films produced by alternate deposition of Ti with V, Mo, or Ta, are desired with individually unique, regular repeating layer thicknesses which range from 1.5 to 15 nm.An initial characterization of the Ti-X composition modulated alloys has been conducted using X-ray diffraction. The pole figure constructions of the various composition wavelengths give a qualitative look at the strain accomodation within the thin films and possible manifestations in mechanical properties.

Microstructures of Ultrathin Films of Sputtered PbTiO3

1994 ◽  
Vol 361 ◽  
Author(s):  
Kiyotaka Wasa ◽  
T. Satoh ◽  
K. Tab Ata ◽  
H. Adachi ◽  
Y. Ichikawa ◽  
...  
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Ultrathin Films ◽  
Crystal Orientation ◽  
Smooth Surface ◽  
Three Dimensional ◽  
Rf Magnetron Sputtering ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dimensional Crystal

ABSTRACTUltrathin films of perovskite PbTiO3, 10–100nm thick, were epitaxially grown on miscut (001)SrTiO3 substrate by rf-magnetron sputtering at 600°C. The electron microscope and high resolution x-ray diffraction analysis suggested the evidence of epitaxial growth of (001)PbTiO3/(001)SrTiO3 with three dimensional crystal orientation. The stoichiometric film shows extremely smooth surface with the surface roughness less than 3nm. Deposition on a miscut substrate under stoichiometric conditions is essential to make continuous thin films of single crystal perovskite PbTiO3.

Sign in / Sign up

Export Citation Format

Share Document