Students Contribute to Our Understanding of Gallium-based Materials

Achievement date: 
2018
Outcome/accomplishment: 

Undergraduate students examined the thermoelectric properties of advanced materials, finding evidence of changed thermoelectric sensitivity at low temperatures. The 2018 spring meeting of the Materials Research Society accepted a paper on their work, which was funded by the Center for Power Optimization of Electro-Thermal Systems (POETS), an NSF-funded Engineering Research Center (ERC) based at the University of Illinois.

Impact/benefits: 

Acceptance of their paper confirmed the value that undergraduate students can bring to advanced research through the Center’s Research Experience for Undergraduates (REU). Their findings added insight into the characteristics of materials based on gallium, which many consider to be a likely replacement for silicon as the backbone of microelectronics.

Explanation/Background: 

Temperature-tolerant sensing devices are needed to advance state-of-the-art power electronics and reach new milestones in space exploration. While silicon has been used successfully to create sensors in the past, these sensors are limited to operation temperatures below 200°C. Emerging materials such as AlGaN/GaN (aluminum gallium nitride/gallium nitride) can withstand higher temperatures.

But their properties are still inferior with respect to predicted performance. There are still many technological hurdles to fully exploiting the enormous potential of these materials. The work of the REU team contributed to our understanding of how these materials suffer from conductivity loss, even at relatively low temperatures.