Exploring the micro- and nano-worlds
Yong-Kyu “YK” Yoon’s investigations into the micro- and nano-worlds have caught the attention of funding agencies, including the National Science Foundation, which has recognized him with two major grants totaling $600,000.
The first, a $399,999 NSF CAREER award—a prestigious award for junior faculty members who are exemplary teachers and scholars—supports Yoon’s research into metamaterials, a curious class of artificial materials that possess qualities not readily found in nature.
Specifically, Yoon, director of UB’s Multidisciplinary nano and Microsystems (MnM) Laboratory, is developing materials that would guide microwaves carrying wireless and broadband signals in unusual ways. He is using micro- and nano-fabrication techniques to create a new generation of metamaterials-based radio frequency (RF) devices with high efficiency, low loss and compact form factors.
Some of these devices will have cloaking and filtering functions useful in military and commercial applications, such as guiding microwaves around tall buildings. Such an invention would find use in cities such as New York City, where communication signals often die as they run into skyscrapers. Yoon’s work is expanding UB’s expertise in integrated nanostructured systems, an area of academic strength the institution is building as part of its UB 2020 long-range strategic plan.
As part of his CAREER award project, Yoon, an assistant professor of electrical engineering, plans to develop a micromachined metamaterials course for advanced microwave applications at UB and an online radio frequency course available to students at UB and the SUNY campuses at Binghamton and Stony Brook.
He also has committed to supervising minority students, supporting the Buffalo-area Engineering Awareness for Minorities program (BEAM), mentoring K-12 pupils, and introducing science and engineering concepts to local middle and high school students through UB’s Science Exploration Day activities. His current work also includes co-leading UB’s Bird Technologies Fellowship Program, which provides scholarships to electrical engineering students working with faculty on research.
A $200,000 NSF grant is supporting Yoon’s inquiries into another area: advanced multidirectional ultraviolet (UV) lithography to fabricate complex, three-dimensional microstructures and nanostructures ranging from miniature arrays of RF antennas shaped like wind vanes to micronozzles that can dispense everything from drugs to ink in a printer. Many scientists employ UV lithography, which involves patterning a polymer with ultraviolet light, to manufacture flat items such as microchip circuits. Yoon’s laboratory is more advanced, capable of utilizing ultraviolet lithography to create objects with greater height. He has filed a patent application for a computerized system to automate lithography procedures previously completed manually.
The micromachining techniques that Yoon is pioneering could advance technologies ranging from tiny, remote-controlled endoscopes that examine patients’ gastrointestinal tract to anti-collision warning systems that use RF signals to determine distance between moving cars. The wireless and broadband communications on which these devices rely travel via high-powered waves with wavelengths of 1 to 10 millimeters. Yoon’s work will make it easier and cheaper to create antennas capable of transmitting and receiving these signals.
Yoon, who earned his PhD in 2004 from the Georgia Institute of Technology and joined the UB faculty in 2006, says microtechnology and nanotechnology is about adventure. He became interested in the world of the small when he saw the 1987 film “Innerspace,” in which a shrunken man in a capsule is injected into the bloodstream of a stranger.