【World Express】Focused on Gallium Oxide Research, UC Santa Barbara PhD Student Receives U.S. Department of Defense NDSEG Fellowship

      Recently, the U.S. Department of Defense (DoD) announced the recipients of the 2025 National Defense Science and Engineering Graduate (NDSEG) Fellowship. Akhila Mattapalli, a Ph.D. student in the Materials Department at the University of California, Santa Barbara (UC Santa Barbara), was selected for this highly competitive honor in recognition of her outstanding research on the wide-bandgap semiconductor β-gallium oxide (β-Ga₂O₃).

      Funded by the DoD, the NDSEG Fellowship supports exceptional doctoral students conducting cutting-edge research in defense-relevant science and engineering fields. The fellowship provides three years of full financial support, including tuition, an annual stipend of $44,400, health insurance, and research travel funds. This year, only 126 students nationwide were selected, underscoring the program’s remarkable competitiveness.

      Under the supervision of Associate Professor Sriram Krishnamoorthy, Mattapalli focuses on the epitaxial growth of β-Ga₂O₃ and its application in high-power electronic devices. As an emerging ultra-wide bandgap (UWBG) semiconductor, β-Ga₂O₃ possesses an exceptionally high breakdown electric field and excellent thermal stability, enabling stable operation under high power density, high frequency, and extreme conditions. It is considered a promising material for next-generation high-voltage transistors and solar-blind ultraviolet (UV) photodetectors.

      Mattapalli’s research aims to fabricate high-quality β-Ga₂O₃ epitaxial films via metal-organic chemical vapor deposition (MOCVD) and to develop vertical transistor architectures that enhance device efficiency and power capability. “A deeper understanding of β-Ga₂O₃ epitaxial growth and its electronic properties is essential for achieving high-performance devices,” said Mattapalli. “As data centers and electronic systems continue to demand higher power-handling capabilities, my project seeks to develop devices that combine performance, efficiency, and reliability under extreme conditions. This research has the potential to significantly reduce global power consumption.”

      Research on β-Ga₂O₃ is regarded as a key direction in the development of fourth-generation semiconductors, with potential applications in power electronics, deep-UV detection, aerospace power systems, and defense electronics. Mattapalli’s receipt of the NDSEG Fellowship further highlights the growing strategic importance of gallium oxide research in the global semiconductor landscape.