Ray Adomaitis received his B.S. and Ph.D. in Chemical Engineering from the Illinois Institute of Technology. After two years working on computational nonlinear dynamics as a postdoctoral researcher at Princeton University, he joined the Institute for Systems Research (ISR) at the University of Maryland as a postdoctoral fellow. Currently, he is a Professor and Associate Chair for Undergraduate Studies in the Chemical and Biomolecular Engineering Department with a joint appointment at the ISR at the University of Maryland. He also is affiliated with the Maryland NanoCenter and the University of Maryland Energy Research Center (UMERC).
Ray's research interests focus on simulation and design of thin-film manufacturing processes with applications in microelectronics, alternative energy, nanomanufacturing, and spacecraft systems. Most of his current efforts are directed to developing physically based models of atomic layer deposition surface reaction kinetics to provide simulation tools for the scale-up and optimizion of these manufacturing processes. His teaching activities include undergraduate and graduate-level classes in solar energy, chemical engineering computations, and capstone process design. Among other awards and activities, he is fellow of the American institute of Chemical Engineers.
American Institute of Chemical Engineers, 2011
Young faculty award
NSF Engineering Education Scholar, 1995
University of Maryland awards
- Teacher of the Year, 1996
- Professor of the Year, 1997
- ISR Outstanding Systems Engineering Faculty Award, 2005
Our research focuses on simulation-based design, optimization, and experimental evaluation of advanced materials manufacturing processes. We are particularly interested in developing new reactor designs for thin-film deposition of semiconductor materials for electronic and solar energy applications.
One of our major areas of activity is in the development of next-generation thin film chemical vapor deposition (CVD) and atomic-layer deposition (ALD) systems. We have developed and tested new reactor design concepts which enable explicit manipulation of the gas-phase composition across the substrate surface during processing, making combinatorial CVD studies and other novel operating modes (including deposition on extremely large substrates) possible. Current work relevant to microelectronic and solar cell manufacturing includes Si CVD, epitaxial growth of III-V compounds, and ALD of metal oxide films.
Important numerical tools developed in our research group in close collaboration with industrial partners include a full-wafer response-surface modeling methodology applicable to the optimization and control of film properties across the entire substrate, and a model-free uniformity control approach based on identifying the Nearest Uniformity Producing Profile (NUPP) for reactor systems with rotating substrates.
Professor Adomaitis currently teaches or has previously taught the following courses:
- ENCH 250: Computer Methods in Chemical Engineering
- ENCH 300: Chemical Engineering Thermodynamics
- ENCH 400: Chemical Engineering Thermodynamics
- ENCH 446: Process Engineering Economics and Design II
- ENCH 468L/648L: Photovoltaics: Solar Energy
- Salami, H., A. Uy, A. Vadapalli, C. Grob, V. Dwivedi, and R. A. Adomaitis, “Atomic layer deposition of ultra-thin indium oxide and indium tin oxide films using a trimethylindium, tetrakis(dimethylamino)tin, and ozone precursor system,” submitted for publication (2018)
- Alobaid, A., C. S. Wang, and R. A. Adomaitis, “Mechanism and kinetics of HER and OER on NiFe LDH films in an alkaline electrolyte,” accepted for publication (2018)
- Adomaitis, R. A. “Estimating the thermochemical properties of trimethylaluminum for thin-film processing applications,” J. Vac. Sci. Tech. A 37 (2018) DOI: 10.1116/1.5045342
- Alobaid, A., H. Salami, and R. A. Adomaitis, “On the computation and interpretation of semi-positive reaction network invariants,” Computers & Chem. Eng. 117 (2018) 236-248 DOI: 10.1016/j.compchemeng.2018.06.009
- Alobaid, A. and R. A. Adomaitis, “Monte Carlo simulation for optimal solar cell configuration,” Proceedings of PSE 2018, (2018)
- Adomaitis, R. A. and K. M. Ng, “Advanced Manufacturing in Chemical Engineering,” Chem. Eng. Progress, October, (2017) 77
- Salami, H., K. Ramakrishnan, and R. A. Adomaitis, “Reaction Path Analysis for Chemical Vapor Deposition and Atomic Layer Deposition Processes: A Study of Titania Thin-Film Deposition,” Physica Status Solidi B, (2017) DOI: 10.1002/pssb.201700091
- Adomaitis, R. A. “Reaction Path Analysis for Atomic Layer Deposition Processes,” Proc. FOCAPO / CPC 2017, Tucson, AZ, (2017)
- Salami, H., A. Poissant, and R. A. Adomaitis, “Anomalously High Alumina Atomic Layer Deposition Growth per Cycle During Trimethylaluminum Under-dosing Conditions,” J. Vac. Sci. Tech. A 35 (2017) 01B101 DOI: 10.1116/1.4963368
- Adomaitis, R. A. “Dynamic Dimension Reduction for Thin-film Deposition Reaction Network Models,” Proc. IFAC DYCOPS-CAB 2016, Trondheim, Norway (2016) 448-453
- Adomaitis, R. A. “Dynamic Order Reduction of Thin-film Deposition Kinetics Models: a Reaction Factorization Approach,” J. Vac. Sci. Tech. A 34 (2016) 01A104 DOI: 10.1116/1.4930591
- Adomaitis, R. A. “Time-Scale Analysis of Atomic Layer Deposition Processes: Predicting the Transition from Mass-Transfer to Kinetically Limited Regimes,” Physica Status Solidi C, 12 (2015) 934-943, DOI: 10.1002/pssc.201510048
- Remmers, E. M., C. D. Travis, and R. A. Adomaitis, “Reaction Factorization for the Dynamic Analysis of Atomic Layer Deposition Kinetics,” Chemical Engineering Science 127 (2015) 374-391 DOI: 10.1016/j.ces.2015.01.051
- Travis, C. D. and R. A. Adomaitis, “Modeling Alumina Atomic Layer Deposition Reaction Kinetics During the Trimethylaluminum Exposure,” Theoretical Chemistry Accounts 133 (2013) 1414, DOI: 10.1007/s00214-013-1414-0
- Travis, C. D. and R. A. Adomaitis, “Dynamic Modeling for the Design and Cyclic Operation of an Atomic Layer Deposition (ALD) Reactor,” Processes 1 (2013) 128-152, DOI: 10.3390/pr1020128
- Travis, C. D. and R. A. Adomaitis, “Modeling ALD Surface Reaction and Process Dynamics using Absolute Reaction Rate Theory,” Chemical Vapor Deposition 19 (2013) 4-14, DOI: 10.1002/cvde.201206985
- Adomaitis, R. A. and A. Schwarm "Systems and Control Challenges in Photovoltaic Manufacturing Processes - A Modeling Strategy for Passivation and Anti-reflection Films,'' Proc. CPC VIII, Savannah, GA (2012).
- Adomaitis, R. A. "A Ballistic Transport and Surface Reaction Model for Simulating Atomic Layer Deposition Processes in High Aspect-Ratio Nanopores,'' Chemical Vapor Deposition, 17 (2011) 353-365, DOI: 10.1002/cvde.201106922.
- Adomaitis, R. A. "Ballistic Transport and Reaction Modeling of Atomic Layer Deposition Manufacturing Processes,'' Proc. 2011 IFAC World Congress, Milan (2011).
- Arana-Chavez, D., E. Toumayan, F. Lora, C. McCaslin, and R. A. Adomaitis "Modeling the Transport and Reaction Mechanisms of Copper Oxide CVD,'' Chemical Vapor Deposition 16 (2010) 336-345, DOI: 10.1002/cvde.201006873.
- Adomaitis, R. A. "Development of a Multiscale Model for an Atomic Layer Deposition Process,'' J. Crystal Growth 312 (2010) 1449-1452, DOI: 10.1016/j.jcrysgro.2009.12.041.
- Guglietta, G. T. Wanga, R. Pati, S. Ehrman, and R. A. Adomaitis "Chemical Vapor Deposition of Copper Oxide Films for Photoelectrochemical Hydrogen Production,'' Proc. of SPIE Vol. 7408 740807-1, Solar Hydrogen and Nanotechnology IV, F. Osterloh, Ed. (2009).
- Dwivedi, V. and R. A. Adomaitis "Multiscale Simulation and Optimization of an Atomic Layer Deposition Process in a Nanoporous Material,'' ECS Transactions 25 (2009) 115-122, DOI: 10.149/1.3207582.
- Leon, M. del Pilar and R. A. Adomaitis "Full Wafer Mapping and Response Surface Modeling Techniques for Thin Film Deposition Processes,'' J. Crystal Growth 311 (2009) 3399-3408.
- Oliver, J. D., B. H. Ponczak, R. P. Parikh, and R. A. Adomaitis "Uniformity Improvement of Planetary Epitaxial Growth Processes through Analysis of Intentionally Stalled SiC Wafers,'' Mat. Sci. Forum, 615-617 (2009) 101-104.
- Adomaitis, R. A. "The Nearest Uniformity Producing Profile (NUPP) Optimization Criterion for Thin-Film Processing Applications,'' J. Process Control 18 (2008) 922-930.
- Sreenivasan, R., R. A. Adomaitis, and G. W. Rubloff "A Comparative Study of Reactor Designs for the Production of Graded Films with Applications to Combinatorial CVD,'' J. Crystal Growth 310 (2008) 270-283.
- Adomaitis, R. A. "Intentionally Patterned and Spatially Non-Uniform Film Profiles in Chemical Vapor Deposition Processes,'' Surface and Coatings Technology 201 (2007) 9025-9029.
- Cai, Y., L. Henn-Lecordier, G. W. Rubloff, R. Sreenivasan, J.-O. Choo, and R. A. Adomaitis, "Multiplexed Mass Spectrometric Sensing in a Spatially Programmable Chemical Vapor Deposition System,'' J. Vac. Sci. Tech. B 25 (2007) 1288-1297.
- Adomaitis, R. A., I. G. Kevrekidis, and R. de la Llave, "A Computer-Assisted Study of Global Dynamic Transitions for a Non-Invertible System,'' Int. J. Bifurcation Chaos 17 (2007) 1305-1321.
- Adomaitis, R. A. "The Trouble with Spurious Eigenvalues,'' Int. J. Bifurcation Chaos 17 (2007) 1375-1381.
- Parikh, R. P., R. A. Adomaitis, J. D. Oliver, and B. H. Ponczak "Implementation of a Geometrically-based Criterion for Film Uniformity Control in a Planetary SiC CVD Reactor System,'' J. Process Control 17 (2007) 477-488.
- Parikh, R. P., R. A. Adomaitis, M. E. Aumer, D. Partlow, D. Thomson, and G. W. Rubloff ``Validating Gallium Nitride Growth Kinetics Using a Precursor Delivery Showerhead as a Novel Chemical Reactor,'' J. Crystal Growth 296 (2006) 15-26.
- Sreenivasan, R. R. A. Adomaitis, and G. W. Rubloff :A Demonstration of Spatially Programmable Chemical Vapor Deposition: Model-Based Uniformity/Non-uniformity Control.'' J. Vac. Sci. Tech. B 24 (2006) 2706-2715.
- Chen, J. and R. A. Adomaitis "An Object-Oriented Framework for Modular Chemical Process Simulation with Semiconductor Processing Applications,'' Computers & Chem. Eng, 30 (2006) 1354-1380.
- Parikh, R. P. and R. A. Adomaitis "An Overview of Gallium Nitride Growth Chemistry and its Effect on Reactor Design: Application to a Planetary Radial-Flow CVD System,'' J. Crystal Growth 286 (2006) 259-278.
- Cho, S. G. W. Rubloff, M. E. Aumer, D. B. Thomson, D. P. Partlow, R. Parikh, and R. A. Adomaitis "In-situ Chemical Sensing in AlGaN/GaN HEMT MOCVD Process for Real-Time Prediction of Product Crystal Quality and Advanced Process Control,'' J. Vac. Sci. Tech. B 23 (4) (2005) 1386-1397.
- Choo, J. O., R. A. Adomaitis, L. Henn-Lecordier, Y. Cai, and G. W. Rubloff "Development of a Spatially Controllable Chemical Vapor Deposition Reactor with Combinatorial Processing Capabilities,'' Review of Scientific Instruments, 76, 062217 (2005).
- Adomaitis, R. A. "Identification of a Deposition Rate Profile Subspace Corresponding to Spatially-Uniform Films in Planetary CVD Reactors: A New Criterion for Uniformity Control,'' Computers & Chem. Eng, 29 (2005) 829-837.
- Choo, J. O., R. A. Adomaitis, G. W. Rubloff, L. Henn-Lecordier, and Y. Liu "Simulation-Based Design and Experimental Evaluation of a Spatially Controllable Chemical Vapor Deposition Reactor,'' AIChE Journal, 51 (2005) 572-584.
- Adomaitis, R. A. "A Reduced-Basis Discretization Method for Chemical Vapor Deposition Reactor Simulation,'' Mathematical and Computer Modeling, 38 (2003) 159-175.
- Adomaitis, R. A. "Objects for MWR,'' Computers & Chem. Eng, 26 (2002) 981-998.
- Adomaitis, R. A. "Spectral Filtering for Improved Performance of Collocation Discretization Methods,'' Computers & Chem. Eng, 25 (2001) 1621-1632.
- Lin, Y.-h. and R. A. Adomaitis, "Simulation and Model Reduction Methods for an RF Plasma Glow Discharge,'' Journal of Computational Physics, 171 (2001) 731-752.
- Chang, H. -Y., R. A. Adomaitis, J. N. Kidder, Jr., and G. W. Rubloff, "Influence of Gas Composition on Wafer Temperature in a Tungsten Chemical Vapor Deposition Reactor: Experimental Measurements, Model Development, and Parameter Estimation,'' J. Vac. Sci. Tech. B, 19 (2001) 230-238; also ISR TR 2000-09.
- Rico-Martinez, R., R. A. Adomaitis, and I. G. Kevrekidis, "Noninvertibility in Neural Networks,'' Computers & Chem. Eng, 24 (2000) 2417-2433.
- Adomaitis, R. A. and Y. -h. Lin, "A Collocation/Quadrature-Based Sturm-Liouville Problem Solver,'' Applied Math. and Computation, 110 (2000); 205-223; also ISR TR 99-1.
- Adomaitis, R. A., Y. -h. Lin, and H. -Y. Chang, "A Computational Framework for Boundary-Value Problem Based Simulations,'' Simulation, 74 (2000) 28-38.
- Lin, Y. -h., H. -Y. Chang, and R. A. Adomaitis, "MWRtools: A Library for Weighted Residual Method Calculations'' Computers & Chem. Eng, 23 (1999) 1041-1061; also ISR TR 98-24.
- Theodoropoulou, A., E. Zafiriou, and R. A. Adomaitis, "Inverse Model Based Real-Time Control for Temperature Uniformity of RTCVD,'' IEEE Trans. Semicond. Manuf., 12 (1999) 87-101.
- Chang, H. -Y. and R. A. Adomaitis, "Analysis of Heat Transfer in a Chemical Vapor Deposition Reactor: An Eigenfunction Expansion Solution Approach,'' Int. J. Heat Fluid Flow, 20 (1999) 74-83; also ISR TR 97-84.
- Lin, Y. -h. and R. A. Adomaitis, "A Global Basis Function Approach to DC Glow Discharge Simulation,'' Phys. Lett. A, 243 (1998) 142-150; also ISR TR 97-81.
- Adomaitis, R. A. and Y. -h. Lin, "A Technique for Accurate Collocation Residual Calculations,'' Chem. Engng J., 71 (1998) 127-134; also ISR TR 98-6.
- Theodoropoulou, A., R. A. Adomaitis, and E. Zafiriou, "Model Reduction for RTCVD Optimization,'' IEEE Trans. Semicond. Manuf. 11 (1998) 85-98; also ISR TR 97-78.
American Institute of Chemical Engineers (AIChE)
- Fellow, 2011
- Physically based modeling for predictive simulation of a net-zero home
- Species-Reaction Graphs for Reaction Network Analysis in Thin-Film Deposition Processes
- Systems Engineering-Based Model Development: Predictive Simulation of a Net-Zero Home
- Thin-film manufacturing process technology
- Materials, Nano, & Bio Research for Systems
- Thin film process simulation and design
- Multiscale ALD and CVD Simulation
- Full Wafer Map Response Surface Models for Combinatorial Chemical Vapor Deposition Systems
- An Object-Oriented Modular Simulation Framework for Semiconductor CVD Processing Systems
- Reaction Kinetics and Transport Model for Gallium Nitride MOVPE Reactor Showerhead Design
- Gas Flow Modeling in MEMS Based Microvalves for Next-Generation CVD Reactor Designs
- Development of a Spatially Controllable Chemical Vapor Deposition System: Preliminary Experimental Evaluation
- Design and Simulation of Mass Spectrometry System Monitor Programmable CVD Process
- Process Sensing and Simulation for GaN-based Semiconductor Electronics