ECE 443 course project highlights: making white LEDs without blue light, optimizing materials in ultraviolet LEDs


Eleanor Wyllie

Students at ECE are designing white LEDs that will not disrupt our sleep cycles and ultraviolet LEDs incorporating more efficient and environmentally conscious materials.

ECE 443 explores the energy conversion devices from fundamentals to system-level issues.
ECE 443 explores the energy conversion devices from fundamentals to system-level issues.

Every spring, the ECE 443 LEDs and Solar Cells course encourages the class to address a grand societal challenge by applying what they’ve learned to create a project. The class explores energy conversion devices to enable energy-efficient and scalable light emitting diodes and solar cells as solutions to the grand challenges in energy, communication, and health.

With support from MicroLink Devices and Crosslight, the class competed in two distinct project competitions: MicroLink Devices Best Project Award and the Crosslight Best Project Award. 

The Crosslight Best Project Award went to Nithiyassri K R T Vivagandan for her project “Designing Blue-Wavelength Free White Light: A Dichromatic Approach Using Violet and Yellow-Green LEDs.” CEO of Crosslight Dr. Simon Li said, “We at Crosslight are delighted to help UIUC to train excellent students in designing optoelectronic devices.”

White artificial light has transformed our society by allowing us to be productive later in the day. However, most white LEDs dominantly contain blue light, which can disrupt sleep cycles and lead to a lower quality of life. Vivagandan aimed to tackle this problem by designing a more efficient blue-wavelength free white light using two complementary-colored LEDs – violet and yellow-green – to obtain a dichromatic white light. 

The MicroLink Devices Best Project Award went to Xizheng Fang for his project “Designing AlGaN-based efficient Ultraviolet Light Emitting Diode.” Noren Pan, CEO of MicroLink Devices commented: “MicroLink Devices is very interested to see advances in compound semiconductors and would like to congratulate Xizheng Fang for his dedication and great effort towards this project.”

Ultraviolet LEDS are essential in many applications, including illumination, optical recording, household air cleaners and high-speed purification of automobile exhaust gases. Fang looked at aluminum gallium nitride (AlGaN) as a semiconductor material to enable high-performance deep-ultraviolet LEDs. As well as their direct, wide and adjustable energy bandgap, AlGaN-based materials boast high-efficiency light emission from quantum wells, hardness and longevity, and environmental safety.

“Considering the COVID pandemic and how UV light sources gained interest due to their disinfection properties, UV LEDs are the ultimate solution to prevent future outbreaks” said Professor Can Bayram, course director and associate professor in electrical and computer engineering.

Find out more about ECE 443 Best Projects.