Jing Zhang, an assistant professor at Rochester Institute of Technology’s Kate Gleason College of Engineering, has received a CAREER award from the National Science Foundation for her work on efficient UV light sources. The $500,000, five-year award will allow Zhang to realize high-efficiency UV photonic devices. The Faculty Early Career Development (CAREER) program supports early-career faculty who have the potential to serve as academic role models in research and education and to lead advances in the mission of their department or organization. Zhang's research group is working to demonstrate that a deeper, fairly unrealized range of the UV light spectrum is as efficient as current near-UV used in today's LED lights. Increasing the efficiencies of optoelectronic devices, specifically using UV LED technologies, could advance important applications in photolithography, 3D printing, purification systems, and a variety of sensing applications. Unfortunately, the further along the UV range, the less efficient the technology becomes. However, Zhang sees promise in preliminary physics analysis and tests on device prototypes. "What I propose to do is on semiconductor-based UV optoelectronic devices, which are efficient [and] compact, and the lifetime of the devices is very long compared to mercury-based, UV light sources," said Zhang. "Semiconductor materials are environmentally friendly compared to mercury-based UV bulbs. That is why this new type of device we are developing is very promising if we can deliver higher efficiencies toward those devices." The UV light spectrum is being explored further because differing aspects react well with certain biological and chemical agents, which are beneficial for biomedical applications. UV light has also been used for air and water purification systems and to cure resins for 3D printers. Advancing these technologies is becoming more important, but the efficiencies of the UV LEDs are low compared to current, visible LEDs, a mature technology that has been commercially available for more than two decades. "Shorter wavelengths with the UV devices have efficiencies In this new project, Zhang will explore use of aluminum gallium nitride, a much wider bandgap material. "We have already developed the fabrication process for the UV LEDs,” Zhang said. “It is already mature in our group. We have developed the physics, and we have promising preliminary results on very initial UV LEDs. We are going to continue the research with these results and see how we can achieve optimized novel device structures."