Rafique’s paper, “Synthesis of Wide Bandgap β-Ga2O3 Rods on 3C-SiC-on-Silicon”, was co-authored by her Ph.D. advisor Hongping Zhao, Assistant Professor of Electrical Engineering and Computer Science; Electrical Engineering doctoral student Lu Han, and Christian A. Zorman, Professor of Electrical Engineering and Computer Science.
Rafique and her co-authors investigated the synthesis of a wide band gap semiconductor material b-Ga2O3 rods (Eg ~4.6-4.9 eV), which are applicable for solar-blind photodetectors, chemical sensing and high power electronic devices.
According to Zhao, “it is still challenging to synthesize high quality wide bandgap Ga2O3 material with fast growth rate”. But Rafique and her co-authors used low pressure chemical vapor deposition (LPCVD) method with optimized growth condition to successfully grow single crystalline b-Ga2O3 rod structures with growth rate up to 14 mm/hr. A new type of substrate 3C-SiC-on-Si (synthesized by Prof. Zorman’s group) was used that enabled the synthesis without using any catalyst.
They demonstrated that, both growth temperature and oxygen concentration during the material synthesis are critical parameters that significantly impact the material morphology and growth rate. Zhao said, “this research is the first time report on the synthesis of b-Ga2O3 on 3C-SiC substrate, which paves a new way toward the synthesis of this material on Si based substrate, compatible for the existing Si technologies.”