Flagship Conference Plays to UVA Engineering’s Strengths in Thin Films, Nano-Science, 2-D Materials and Ferroelectrics

Students and faculty of UVA’s Department of Materials Science and Engineering continued a long-standing engagement with the American Vacuum Society by chairing sessions, presenting papers and earning top honors at the 2019 international symposium and exhibition, or AVS 66. Since its founding in 1953, the organization has evolved into an interdisciplinary society covering topics related to both vacuum and emerging technologies in materials, interfaces and processing fields.

“Every fall, those of us who grow thin films and study surfaces and interfaces make our way to the AVS annual meeting,” said Petra Reinke, professor of materials science and engineering and program chair of the Surface Science Division for AVS 66. “AVS creates an intersection for everyone who works in this field, and offers unique opportunities to advance our research,” Reinke said. “Networking opportunities, talks and posters about exciting new discoveries combine for a great experience. Each year AVS creates open spaces to let our minds roam; this is where ideas bloom best.”   

Several UVA materials science and engineering faculty assist in planning or leading technical sessions. Catherine Dukes, director of the department’s Laboratory for Astrophysics and Surface Physics, chaired the session on operando surface science and astrochemistry with Reinke. “This was absolutely my favorite session,” Dukes said. “There were so many exciting applications of surface physics—everything from studies of ices in the intersteller medium to real-time reaction studies of high-temperature catalysts. The presentations were top-notch.”

“AVS is an outstanding opportunity to introduce our students to what people around the world are doing,” said Stephen J. McDonnell, assistant professor of materials science and engineering. McDonnell serves on the executive committee of the society’s electronic materials/photonics division. “It connects academics and industry and gives students a first look at cutting-edge equipment and instrumentation.”

James Fitz-Gerald, professor of materials science and engineering, is a long-time champion of UVA Engineering’s participation in American Vacuum Society symposia and related activities. “AVS showcases research that plays to our strengths,” Fitz-Gerald said. UVA Engineering students shared advances in thin films, nano-science, 2-D materials and materials used in electronics and integrated circuits.

Here are few highlights from the students’ presentations:

Peter Litwin won top poster in electronic and photonics materials for growing high quality transition metal dichalcogenides, a class of 2-D materials that includes semiconducting and metallic nanomaterials. Litwin is a Ph.D.student advised by McDonnell. Conducting his research in collaboration with Costel Constantin, associate professor of physics and astronomy at James Madison University, Litwin used a combination of surface characterization techniques to study the chemistry and morphology of grown tungsten diselenide. Litwin demonstrated tunability of the growth parameters of this compound to control and optimize its properties.

Jonathan Skelton, a Ph.D. student studying with Fitz-Gerald and Professor Jerrold Floro, presented a poster in the nanoscale science session. Skelton introduced an approach to make nanoscale lamellae in eutectic alloys through laser powder bed fusion, a form of additive manufacturing. This fabrication technique offers a unique possibility to tailor the materials’ microstructure within an additively manufactured component. This research has potential applications in high-strength alloys as well as the field of thermoelectric devices.

Anna Costine, a Ph.D. student in Reinke’s group, presented a new way to make silicene and silicene ribbons, a novel 2-D material with potential applications in electronics and quantum science. Synthesizing silicene is difficult; making it on a support that allows integration in electronic devices is even more challenging. Costine’s work includes experiments conducted at Oak Ridge National Laboratory, where she used low-temperature imaging at the atomic scale to understand silicene and silicene nanoribbons’ electronic properties and synthesis.

Will Blades, a Ph.D. student and one of Reinke’s advisees, shared new atomic-scale models of early stage oxidation and corrosion of transition metals such as nickel-chromium and nickel-chromium tungsten alloys. Blades’ observations of these surface-level atomic reaction pathways contribute to the wider effort to develop an end-to-end process model to predict oxidation behavior on transition metal surfaces, which in turn facilitates the development of alloys with better corrosion resistance.

Meg Sales, a Ph.D. student in McDonnell’s group, presented research on the growth, interface chemistry and thermal stability of metal dichalcogenides at a session on new devices and materials for logic and memory. Ferroelectric materials are highly applicable in memory devices, but do not pair well with silicon. The 2-D nature of transition metal dichalcogenides suggests a promising, high-quality alternative interface for ferroelectric-based transistor devices.

The American Vacuum Society will convene its 67th international symposium this October in Denver, Colorado. “We’re very proud of our students’ strong showing in 2019 and look forward to sharing new developments in micro- and nano-scale in fields like heat transfer, catalysis and 2-D materials at this year’s gathering,” Reinke said.