Electrodeposition simulation

H. Li, F. Czerwinski, J. A. Szpunar. Monte-Carlo simulation of texture and microstructure development in nanocrystalhne electrodeposits. Nanostruct Mater 9 673, 1997. 

A hanging mercury drop electrodeposition technique has been used [297] for a carbon filament flameless atomic absorption spectrometric method for the determination of copper in seawater. In this method, copper is transferred to the mercury drop in a simple three-electrode cell (including a counterelectrode) by electrolysis for 30 min at -0.35 V versus the SCE. After electrolysis, the drop is rinsed and transferred directly to a prepositioned water-cooled carbon-filament atomiser, and the mercury is volatilised by heating the filament to 425 °C. Copper is then atomised and determined by atomic absorption. The detection limit is 0.2 pg copper per litre simulated seawater. 

Boltzmann term, 1078 computer simulation. 1161 current density, 1078, 1081 current potential relation, 1082 doping, 1073 effect of light on, 785 -/junction, 1081 electrode kinetics of, 170 electrodeposition on, 1344... 

In a similar spirit, Alkire, Braatz and co-workers developed coupled hybrid continuum-KMC simulations to study the electrodeposition of Cu on flat surfaces and in trenches (Drews et al., 2003b, 2004 Pricer et al., 2002a, b). A 3D KMC simulation accounted for the surface processes as well as diffusion in the boundary layer next to the surface, whereas a ID or 2D continuum model (with adaptive mesh) was applied to simulate the boundary layer farther away. In... 

His research group successfully started extensive investigations on the electrodeposition of silver [24—26] and gold [26] nanoparticles on graphite surfaces. Combined with Brownian dynamic simulations for the growth of metal nanoparticle ensembles [22, 23], the work focused on the development of nontemplate, electrochemical routes to dimensionally uifiform metal structures. 

An Analysis of Feature-Scale Simulation of Patterned Electrodeposition. 144... 

Perhaps the first numerical investigation of lithographically patterned electrodeposition was published by Alkire et al. [46]. In this work, the finite-element method was used to calculate the secondary current distribution at an electrode patterned with negligibly thin insulating stripes. (This is classified as a secondary current distribution problem because surface overpotential effects are included but concentration effects are not.) Growth of the electrodeposit was simulated in a series of pseudosteady time steps, where each node on the electrode boundary was moved at each... 

Fig. 21. Four simulated shape histories for nickel electrodeposition into a 50 p V groove on a ratating disk electrode with coumarin as a leveling agent. (A) No coumarin present (C-D) 0.68 mM coumarin at 150, 360, and 900 r. p. m. (Reprinted by permission of the publisher, The Electrochemical Society, Inc. [58]).

It is therefore appropriate to list a number of noteworthy general observations and trends related to microfabrication by electrodeposition, deposit uniformity, and the use of numerical simulation. 

Enough is known about the fundamental forces that determine the current distribution to carry out fairly accurate simulations of simple systems. Although in the electronics industry predictions are currently quite useful for guiding the design and production of components made by patterned electrodeposition, there is ample opportunity for improvement, especially in the following areas. 

Figure 4.4 Six configurations computed during the KMC simulation of the electrodeposition ofcopperon a substrate (grey spheres) in the presence of additives (red and green spheres) to form a copper film 2-3 atoms thick [183, 184],...

Figure 4.5 The set of transition probabilities from a specific configuration cto a large number of alternative configurations involving a single reaction step (surface diffusion, adsorption, desorption, surface reaction) during the KMC simulation of the electrodeposition of copper.

The coarse-grained approach utilizes a simplified system representation with fewer degrees of freedom, resulting in faster simulations but with reduced spatial and/or temporal resolution [97-99]. Different coarse-graining (CG) schemes have been devised to preserve the most relevant properties of the molecular system. Such methods can be applied to describe time scales that are far beyond the scope of allatom M D or KMC simulations, and thus extend the scope of molecular simulation to the nanoscale. Some examples of successful application of CG methods are the simulation of the different phases of the lipid-water system, interactions of peptides and proteins with biological membranes, and the electrodeposition of copper to form nanowires, nanofilms and nanoclusters in kinetic-limited regimes [182]. 

Figure 4.7 Schematic of the dynamically coupled multiscale simulation of the electrodeposition of copper into a trench to form a copper wire. A finite volume code that simulates the potential field and concentration fields of all chemical species in aqueous solution sends the solution concentrations and potential at the solid-liquid interface to a KMC code, which simulates adsorption, desorption and chemical and electrochemical reactions that occur on the surface. The KMC code...

Carlo Simulation of Copper Electrodeposition with Additives. Int. ]. Multiscale Comput. Eng., 2, 313-327. 

He, Y., Braatz, R. and Alkire, R. (2007) Effect of Additives on Shape Evolution during Electrodeposition. I. Multiscale Simulation with Dynamically Coupled Kinetic Monte Carlo and Moving-Boundary Finite-Volume Codes. /. Electrochem. Soc., 154, D230-D240. 

R.C. (2005b) Coupled Mesoscale-Continuum Simulations of Copper Electrodeposition in a Trench. AIChE/., 50, 226-240. 

Drews, T.O., Braatz, R.D. and Alkire, R.C. (2007) Monte Carlo Simulation of Kinetically-limited Electrodeposition on a Surface with Metal Seed Clusters. Z. Phys. Chem., 221, 1287-1305. 

Simulations of copper electrodeposition in sub-micron features in the presence of a leveling agent indicate that the formation of void-free deposits requires tight control of the operating conditions. For very small features, primarily one dimensionless group (equation 7) dictates the leveling capability of a process. Results also indicate that as feature size is reduced, the deposition tends to become conformal unless the additive chemistry is modified. It is proposed that conformal deposit is not desirable because random variations in deposition rate will lead to void formation in a statistically significant number of features on a wafer. 

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