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Search Publications by: Daniel Wheeler (Fed)

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Displaying 1 - 25 of 53

Phase Field Benchmark Problems for Nucleation

June 1, 2022
Wenkun Wu, David M. Taboada, Jonathan E. Guyer, Peter W. Voorhees, James A. Warren, Daniel Wheeler, Tamas Pusztai, Laszlo Granasy, Olle G. Heinonen
We present nucleation phase field model benchmark problems, expanding on our previous benchmark problems on diffusion, precipitation, dendritic growth, linear elasticity, fluid flow and electrochemistry. Nucleation is the first step in the formation of

How important is microstuctural feature selection for data-driven structure-property mapping?

January 6, 2022
Hao Liu, Berkay Yucel, Daniel Wheeler, Baskar Ganapathysubramanian, Surya Kalidindi, Olga Wodo
Data-driven approaches now allow for systematic mapping of microstructure to properties. In particular, we now have d\ iverse approaches to "featurize" microstructures, creating a large pool of machine-readable descriptors for subsequent stru\ cture

PFHub: The Phase-Field Community Hub

April 17, 2019
Daniel Wheeler, Trevor Keller, Jonathan E. Guyer, James A. Warren, Stephen DeWitt, Andrea Jokisaari, Daniel Schwen, Larry Aagesen, Olle Heinonen, Michael Tonks, Peter Voorhees
An online portal provides a valuable space for scientific communities to summarize a shared challenge, collect attempts at a solution, and present a quantitative comparison of past attempts in a compelling way. An exemplar of such a portal is μMAG. The

Microstructure Knowledge Systems for Capturing Process-Structure Evolution Linkages

June 14, 2017
James A. Warren, Daniel Wheeler, David Brough, Surya Kalidindi
This paper develops and demonstrates a novel data science framework for capturing and communicating critical information regarding the evolution of material structure in spatiotemporal multiscale simulations of various processing operations employed by the

Spatial-Temporal Modeling of Extreme Bottom-Up Filling of Through-Silicon-Vias

December 6, 2013
Daniel Wheeler, Thomas P. Moffat, Daniel Josell
Extreme bottom-up superfilling of annular through-silicon-vias (TSV) during copper electrodeposition has been reported wherein metal deposits on the bottom surface of the TSV with negligible deposition on its sidewalls or the field around it. The growth

Modeling Extreme Bottom-Up Filling of Through Silicon Vias

August 29, 2012
Daniel Josell, Daniel Wheeler, Thomas P. Moffat
Extreme bottom-up superfilling of through silicon vias (TSV) was recently described wherein deposition occurs on the bottom surface of the vias with negligible deposition on their sidewalls or the field around them. The process uses a deposition

Predicting Microstructure Development During Casting of Drug Eluting Coatings

September 19, 2010
David M. Saylor, Jonathan E. Guyer, Daniel Wheeler, James A. Warren
We have devised a novel diffuse interface formulation to model the development of chem- ical and physical inhomogeneities, i.e. microstructure, during the process of casting drug eluting coatings. These inhomogeneities, which depend on the coating

Modeling Reactive Wetting when Inertial Effects are Dominant

June 30, 2010
Daniel Wheeler, James A. Warren, William J. Boettinger
Recent experimental studies of molten metal droplets wetting and spreading on high temperature reactive substrates have established that the majority of triple-line motion occurs when inertial effects are dominant. In light of these studies, this paper

FiPy: PDEs in Python

February 23, 2009
Jonathan E. Guyer, Daniel Wheeler, James A. Warren
Partial differential equations (PDEs) are ubiquitous to the mathematical description of physical phenomena. They describe the relationships between functions of more than one independent variable and partial derivatives with respect to those variables

A Finite Volume PDE Solver Using Python (FiPy)

October 16, 2008
Jonathan E. Guyer, Daniel Wheeler, James A. Warren
We present an object oriented partial differential equation (PDE) solver written in Python based on a standard finite volume (FV) approach.The solution of coupled sets of PDEs is ubuquitous in the numerical simulation of science problems. Numerous PDE

Control of Overfill Bumps in Damascene Cu Electrodeposition

October 16, 2008
Soo K. Kim, Daniel Wheeler, Daniel Josell, Thomas P. Moffat
Electroanalytical measurements and feature filling experiments have been conducted to study the effect of dodecyltrimethylammonium chloride (DTAC) and branched polyethyleneimine (PEI) on Cu deposition as levelers in the presence of various combinations of

Modeling Superconformal Electrodeposition Using an Open Source PDE Solver

October 16, 2008
Daniel Wheeler, Jonathan E. Guyer
Superconformal electrodeposition enables the void-free filling of high aspect ratio features such as trenches or vias in the Damascene metallization process. Superconformal electrodeposition, also known as superfill, occurs when particular combinations of

Superfilling When Adsorbed Accelerators Are Mobile

February 6, 2007
Daniel Josell, Thomas P. Moffat, Daniel Wheeler
Bottom-up superfill during electrodeposition that is used for industrial processing of damascene copper interconnects has also been demonstrated during electrodeposition of silver and gold. The Curvature Enhanced Accelerator Coverage (CEAC) mechanism has

Curvature Enhanced Adsorbate Coverage Model for Electrodeposition

January 11, 2006
Thomas P. Moffat, Daniel Wheeler, Soo K. Kim, Daniel Josell
The impact of leveling additives acting through the traditional leveling mechanism of accumulation and consumption has been coupled with the Curvature Enhanced Accelerator Coverage (CEAC) mechanism previously used to explain bottom-up superfill of features

Gold Superfill in Sub-Micrometer Trenches: Experiment and Prediction

November 16, 2005
Daniel Josell, Daniel Wheeler, Thomas P. Moffat
Bottom-up deposition of gold in fine trenches, also called superfill, was recently demonstrated using a submonolayer coverage of preadsorbed, deposition-rate-accelerating lead followed by gold electrodeposition. The present study has used experiments on

FiPy: A Finite Volume PDE Solver Using Python

September 1, 2005
Daniel Wheeler, Jonathan E. Guyer, James A. Warren
The solution of coupled sets of partial differential equations (PDEs) is ubiquitous in continuum models for phase transformations, such as in phase field or level et simulations. We are developing an object-oriented PDE solver, written in the Python

Superconformal Deposition and the CEAC Mechanism

February 27, 2004
Thomas P. Moffat, Daniel Wheeler, Daniel Josell
The mechanism and modeling of superconformal film growth used in the electrochemical fabrication of 3-D Cu interconnects is briefly reviewed. The central role of electrolyte additives in controlling feature filling is fully described by the curvature