The article "Ultrawide-Bandgap Semiconductors: Research Opportunities and Challenges" by J. Y. Tsao et al. explores the emerging field of ultrawide-bandgap (UWBG) semiconductors, which have bandgaps significantly wider than those of conventional materials like GaN. These materials, including AlGaN, diamond, and Ga2O3, offer potential advantages in high-power and RF electronics, deep-UV optoelectronics, quantum information, and extreme-environment applications due to their superior performance metrics. The authors review the historical context of semiconductor technology, highlighting the development of narrower bandgap materials such as Ge, Si, and III-V compounds, and the recent breakthroughs in wide-bandgap materials like InGaN. They discuss the current state of UWBG materials, emphasizing the challenges and opportunities in material synthesis, device physics, and application development. Key challenges include the lack of high-quality single-crystal substrates, the immaturity of heteroepitaxy techniques, and the need for predictive frameworks to guide material growth. The article also outlines research opportunities, such as the development of large-diameter single-crystal substrates, improved heteroepitaxy techniques, and the exploration of novel device architectures. Overall, the article aims to serve as a research agenda for the UWBG community, fostering advancements in this promising area of semiconductor technology.The article "Ultrawide-Bandgap Semiconductors: Research Opportunities and Challenges" by J. Y. Tsao et al. explores the emerging field of ultrawide-bandgap (UWBG) semiconductors, which have bandgaps significantly wider than those of conventional materials like GaN. These materials, including AlGaN, diamond, and Ga2O3, offer potential advantages in high-power and RF electronics, deep-UV optoelectronics, quantum information, and extreme-environment applications due to their superior performance metrics. The authors review the historical context of semiconductor technology, highlighting the development of narrower bandgap materials such as Ge, Si, and III-V compounds, and the recent breakthroughs in wide-bandgap materials like InGaN. They discuss the current state of UWBG materials, emphasizing the challenges and opportunities in material synthesis, device physics, and application development. Key challenges include the lack of high-quality single-crystal substrates, the immaturity of heteroepitaxy techniques, and the need for predictive frameworks to guide material growth. The article also outlines research opportunities, such as the development of large-diameter single-crystal substrates, improved heteroepitaxy techniques, and the exploration of novel device architectures. Overall, the article aims to serve as a research agenda for the UWBG community, fostering advancements in this promising area of semiconductor technology.