Energy | Materials Science and Engineering at Penn State

Suzanne Mohney

Suzanne Mohney
Professor of Materials Science and Engineering and Electrical Engineering
N-209 Millennium Science Complex
(814) 863-0744
mohney@matse.psu.edu
www.esm.psu.edu/mohney/

Biographical Sketch:

Suzanne Mohney has been a Professor of Materials Science and Engineering since 2004 and holds the title of Professor of Electrical Engineering. Prior to 2004, she was an Associate or Assistant Professor at Penn State. She earned a Ph.D. in Materials Science at the University of Wisconsin in 1994 and a B.S.Ch.E. summa cum laude from Washington University in St. Louis in 1987. She has been a recipient of research awards from The Electrochemical Society and the Penn State College of Earth and Mineral Science, as well as an award for outstanding teaching from the College. She currently serves as the Editor-in-Chief of the TMS-IEEE Journal of Electronic Materials.

Research Interests:

Electronic materials
Metals in electronics
Compound semiconductors
Wide band gap semiconductors

Areas of Research:

Our research group investigates electronic and photonic materials. Many of our projects focus on metal/semiconductor contacts for electronic and optoelectronic devices. We are also investigating semiconductor nanowires for nanoscale electronics and quantum dots for more efficient white lighting. In addition, we study metallic thin films for interconnects, electronic packaging, and microelectromechanical systems (MEMS).
The metal/semiconductor contacts we study are an essential part of electronic and optoelectronic devices, including transistors, laser diodes, and solar cells. Controlled metallurgical reactions between the contact metals and the semiconductor are required to engineer the electrical properties of the contacts. On the other hand, uncontrolled reactions can result in nonuniform contacts and poor thermal stability during processing, packaging, or long-term operation. Through an examination of the thermodynamics and kinetics governing interfacial reactions, contacts with greatly improved thermal stability, uniformity, and electrical performance can be designed. This work also involves study of current transport in the contacts and materials characterization using techniques such as transmission electron microscopy, Auger depth profiling, and atomic force microscopy. We work with many families of semiconductors, some of which have been commercialized and others that are in the early stages of development. These materials include III-V compound semiconductors, GaN, SiC, and Si.
Our research on semiconductor nanowires and quantum dots, MEMS, and novel semiconductors is very interdisciplinary, involving collaborations with faculty in electrical engineering, physics, chemical engineering, and other materials disciplines. We also frequently work with researchers from government laboratories and industry.

Technology Impacted By Research:

Microelectronics
Energy
Communication
Lighting

Journal Articles and Publications:

C. M. Eichfeld, S. S. A. Gerstl, T. Prosa, Y. Ke, J. M. Redwing and S. E. Mohney, “Local Electrode Atom Probe Analysis of Silicon Nanowires Grown with an Aluminum Catalyst,” Nanotechnology 23, 215205 (2012).
F. Zhang, J. Liu, G. J. You, C. F. Zhang, S. E. Mohney, M. J. Park, J. S. Kwak, Y. Q. Wang, D. D. Koleske, and J. Xu, “Nonradiative Energy Transfer Between Colloidal Quantum Dot-Phosphors and Nanopillar Nitride LEDs,” Optics Express 20, A333–A339 (2012).
J. A. Howell, S. E. Mohney, and C. L. Muhlstein, “Developing Ni-Al and Ru-Al Thin Films for Microelectromechanical Systems,” J. Vac. Sci. Technol. B 29, 042002–13 (2011).
B. P. Downey, J. R. Flemish, and S. E. Mohney, “Investigation of Polarity Effects on the Degradation of Pd/Ti/Pt Ohmic Contacts to p-type SiC Under Current Stress,” J. Vac. Sci. Technol. B 29, 061205 (2011).
K. Sarpatwari, S. E. Mohney, and O. O. Awadelkarim, “Effects of Barrier Height Inhomogeneities on the Determination of the Richardson Constant,” J. Appl. Phys. 109, Article 014510 (2011).
B. P. Downey, S. Datta, and S. E. Mohney, “Numerical study of reduced contact resistance via nanoscale topography at metal/semiconductor interfaces,” Semicond. Sci. Tech. 25, Article 015010 (2010).
K. Sarpatwari, N. S. Dellas, O. O. Awadelkarim, and S. E. Mohney, “Extracting the Schottky barrier height from axial contacts to semiconductor nanowires,” Solid-State Electron. 7, 689–685 (2010).
N. S. Dellas, J. Liang, B. J. Cooley, N. Samarth, and S. E. Mohney, “Electron microscopy of MnAs/GaAs core/shell nanowires,” Appl. Phys. Lett. 97, 072505 (2010).
R. Dormaier, Q. Zhang, B. Liu, Y. C. Chou, M. D. Lange, J. M. Yang, A. K. Oki, and S. E. Mohney, “Thermal Stability of Pd/Pt/Au Contacts to InAlAs/InAs Heterostructures for High Electron Mobility Transistors,” Journal of Applied Physics 105, Article 044505 (2009).
N. S. Dellas, B. Z. Liu, S. M. Eichfeld, C. M. Eichfeld, T. S. Mayer, and S. E. Mohney, “Orientation Dependence of Nickel Silicide Formation in Contacts to Silicon Nanowires,” Journal of Applied Physics 105, Article 094309 (2009).

Mohney

Kwadwo Osseo-Asare

Kwadwo Osseo-Asare
Distinguished Professor of Metallurgy and
Energy and Geo-environmental Engineering
208 Steidle Building
(814) 865-4882
asare@matse.psu.edu

Biographical Sketch:

Coming soon.

Research Interests:

Aqueous Processing: Materials Synthesis & Processing
Nanoparticle Synthesis, Purification, and Assembly
Wet Processing in Semiconductor Fabrication
Chemical-Mechanical Polishing, Surface Cleaning & Finishing
Hydrometallurgy
Separation Science & Technology
Environmental Systems
Applied Aqueous Chemistry: Interfacial and Colloidal Phenomena
Surfactant Science
Semiconductor Electrochemistry
Thermodynamic Modeling

Areas of Research:

Coming soon.

Technology Impacted By Research:

Coming soon.

Journal Articles and Publications:

X. Zeng, J. Quaye, and K. Osseo-Asare "Partition of Hematite in the Triton X-100/Dextran Aqueous Biphase System", Colloids Surf., 246, 135-145 (2004).
P. Suphantharida and K. Osseo-Asare, "Cerium Oxide Slurries in Chemical-Mechanical Polishing: Electrophoretic Mobility and Adsorption Investigations of Ceria/Silicate Interaction", J. Electrochem. Soc., 151, G658-G662 (2004).
Q. Liu and K. Osseo-Asare, "Synthesis of Monodisperse Al-Substituted Hematite Particles from Highly Condensed Metal Hydroxide Gels", J. Colloid Interface Sci., 231, 401-403 (2000).
F. J. Arriagada and K. Osseo-Asare, "Synthesis of Nanosize Silica in a Nonionic Water-in-Oil Microemulsion: Effects of the Water/Surfactant Molar Ratio and Ammonia Concentration", J. Colloid Interface Sci., 211, 210-220 (1999).
D. Wei, and K. Osseo-Asare, "Semiconductor Electrochemistry of Particulate Pyrite: Mechanisms and Products of Dissolution. J. Electrochem. Soc. , 144, 546-553 (1997).

Osseo-Asare

T.C. Mike Chung

T. C. Mike Chung
Professor of Materials Science and Engineering
325 Steidle Bldg.
(814) 863-1394
chung@matse.psu.edu

Biographical Sketch:

Professor Chung obtained his B. S. in Chemistry from Chung Yuan University (Taiwan) in 1976. He came to the U. S. for his graduate study in the Department of Chemistry, University of Pennsylvania in 1979. After finishing his Ph.D work in 1982 on conducting polymers (with Professor A. J. MacDiarmid, Nobel Laureate), he spend two years as a Research Scientist at Institute for polymers and Organic Solids (with Professor Alan J. Heeger, Nobel Laureate), University of California, Santa Barbara. Between 1984 and 1989, he was a Senior Research Staff in Corporate Research, Exxon Company. In 1989 he joined the faculty of the Pennsylvania State University as an associate professor and became professor of Polymer Science in the Department of Materials Science and Engineering in 1993. He is author of about 200 professional publications, including 2 books and 45 U.S. patents.

Research Interests:

Functionalization of polyolefins via the combination of metallocene catalysts and reactive chain transfer agents
Functionalization of fluoropolymers using borane-mediated radical polymerization
Living radical polymerization based on new borane/oxygen initiators
Energy storage via polymer thin film capacitors with high energy density, high power density, and low loss.
Polyolefin-based ion conductors for fuel cells, batteries, electrodialysis, etc.
Oil super-absorbent polymers (oil-SAP) for oil spill recovery and natural gas storage
B/C/M graphitic materials for hydrogen storage

Areas of Research:

Professor Chung is interested in the development of new polymer chemistry that can lead to new materials with unique chemical and physical properties for applications. In his recent research activities, he has been focusing on the technologies relative to energy and environmental issues. Several current research projects include (a) functionalization of polyolefins (PE, PP, EP, etc.) via the combination of metallocene catalysts and reactive comonomers and chain transfer agents to prepare polyolefins containing side-chain or chain-end functional groups, (b) synthesis of long chain branched polyolefin, including i-PP and s-PS, and studying their thin film processing, (c) studying control radical polymerization based on new functional borane/oxygen initiators to prepare functional fluoropolymers, (d) developing new energy storage technology on the polymer thin film capacitors with high energy density, high power density, and low loss, (e) studying new polyolefin-based ion conductors that show high ion conductivity, good fuel selectivity, long term stability, and cost effective, (f) investigating new polyolefin-based oil superabsorbent (oil-SAP) for oil spill recovery, (g) synthesizing boron substituted carbon (B/C) materials and doped derivatives for hydrogen storage. My group at Penn State is recognized as a leading research group in the functionalization of polyolefin and fluoropolymers with more than 180 papers and 50 US and international patents published in the past 20 years.

Technology Impacted By Research:

In light of the 2010 BP disaster in Gulf of Mexico and the 2011 Exxon oil spill in Yellowstone river, showing no effective technology for recovering oil spills and preventing pollution in the air and water, we have recently developed a new polyolefin-based oil super-absorbent polymer (oil-SAP) that exhibits high oil absorption capability (up to 50 times of its weight), fast kinetics, easy recovery from water surface, and no water absorption. The recovered oil/oil-SAP solid is suitable for regular refining process (no pollutants and no wastes). This cost effective new oil-SAP technology shall dramatically reduce the environmental impacts from oil spills and recover most of precious natural resource.

Journal Articles and Publications:

"Functionalization of Polyolefins", T. C. Chung, Academic Press, London, 2002
Synthesis of Functional Polyolefin Copolymers with Graft and Block Structures, T. C. Chung, Progress in Polymer Science 2002, 27, 39.
Ferroelectric Polymers with Giant Electrostriction; Based on Semicrystalline VDF/TrFE/CTFE Terpolymers, T. C. Chung and A. Petchsuk, Ferroelectrics Letters 2001, 28, 135.
Exfoliated PP/Clay Nanocomposites Using Ammonium-Terminated PP as the Organic Modification Montmorillonite, Z. M. Wang, H. Nakajima, E. Manias, and T. C. Chung, Macromolecules 2003, 36, 8919.
Reaction Mechanism of Borane/Oxygen Radical Initiators During the Polymerization of Fluoromonomers, Zhi-cheng Zhang and T. C. Mike Chung, Macromolecules 2006, 39, 5187.
Synthesis and Characterization of Long Chain Branched Isotactic Polypropylene (LCBPP) via Metallocene Catalyst and T-reagent, J. A. Langston, R. H. Colby, F. Shimizu, T. Suzuki, M. Aoki, T. C. Mike Chung, Macromolecules 2007, 40, 2712.
Fluoro-terpolymer Based Capacitors Having High Energy Density, Low Energy Loss, and High Pulsed Charge-discharge Cycles, Zhicheng Zhang, and T. C. Mike Chung, Macromolecules 2007, 40, 783.
Synthesis of Boron-Substituted Carbon (B/C) Materials Using Polymeric Precursors and Evaluation for Hydrogen Physisorption, Youmi Jeong, Alfred Kleinhammes, Yue Wu, and T. C. Mike Chung, J. Am. Chem. Soc. 2008, 130, 6668.
Super-activated Carbon Containing Substitutional Boron (BC_x): Synthesis, Characterization, and Applications in Hydrogen Storage, Youmi Jeong and T. C. Mike Chung, Carbon 2010, 48, 2526.
Synthesis of Functionalized Isotactic Polypropylene Dielectrics for Electric Storage Application, Xuepei Yuan, Yuichi Matsuyama, and T.C. Mike Chung, Macromolecules 2010, 43, 4011.

Chung