Joan M. Redwing received her B.S. in Chemical Engineering from the University of Pittsburgh and her Ph.D. in Chemical Engineering from the University of Wisconsin-Madison. After receiving her Ph.D., she was employed as a research engineer at Advanced Technology Materials, Inc. where she worked on the development of group III-nitride materials and devices. Dr. Redwing joined the faculty of the Department of Materials Science and Engineering at Penn State University in 2000. She holds appointments in the Department of Electrical Engineering and the Department of Chemical Engineering at Penn State and is a member of the Materials Research Institute. Dr. Redwing’s research interests are in the general area of electronic materials synthesis and characterization with a specific emphasis on semiconductor thin film, nanowire and 2D materials fabrication by chemical vapor deposition. She currently serves as secretary of the American Association for Crystal Growth and is an associate editor for the Journal of Crystal Growth and the Journal of Materials Research. She is a co-author on over 250 publications in refereed journals and holds 8 U.S. patents.
Dr. Redwing’s research interests lie in the general area of electronic and optoelectronic materials synthesis and characterization with a special emphasis on chemical vapor deposition processing of semiconductor thin films and nanomaterials.
The development of wide bandgap group III-nitride (AlGaInN) thin films and device structures by metalorganic chemical vapor deposition is an area of continuing research. Group III-nitrides are widely used in light emitting diodes for solid state lighting and in power transistors for radar and communications. The development of group III-nitride devices, however, is often limited by film cracking which results from intrinsic and extrinsic stress due to lattice and thermal expansion mismatches between the film and substrate. The research is focused on the use of in-situ techniques to study dynamic changes in film stress during growth to gain insight into mechanisms of stress generation and relaxation. The growth of group III-nitrides on silicon and other novel substrates is an area of current interest.
The growth of semiconductor nanowires using metal-mediated chemical vapor deposition is another area of active research. The nanowire growth process, known as vapor-liquid-solid growth, uses a metal nanoparticle to promote the growth of nanoscale wires of silicon, germanium and III-V materials. This work is aimed at understanding the fundamental mechanisms of nanowire growth, the role of the metal particle in the growth process and the fabrication of axial and radial junction device structures. The integration of semiconductor nanowires in photovoltaic devices is an area of interest.
A new area of research focuses on the development of chemical vapor deposition techniques for the synthesis of layered semiconductors and two-dimensional transition metal chalcogenide films for applications in nanoelectronics and solar energy. This work is focused on developing processes for self-limited growth and assembly of monolayer and multilayer chalcogenide films and characterization of layer properties.