（This article is reposted from a personal WeChat offical account.）

      The U.S. Department of Energy conducted a round of research on GAN-based optical switching devices from 2018 to 2023, extending PCSS technology originally aimed at high-power microwaves and high-voltage pulse sources to high-voltage power grids, but failed to achieve the expected results.

      Entering 2025, global attention has turned to Gallium Oxide, especially the 8-inch β-Ga₂O₃ wafers with a cost expected to drop to 200 yuan per piece. Their high critical breakdown electric field and excellent robustness are considered to be highly suitable for the demands of high-voltage power grids.

      From the end of 2024 to the beginning of 2025, the writer had in-depth exchanges with multiple research institutions both at home and abroad on the concept of "Gallium Oxide 10,000-Volt 1,000-Amp PCAS >20kV Ultra-High Voltage Optical Conduction Auxiliary Switch Devices". At that time, only one related paper published by researchers from the Lawrence Laboratory in the United States could be found in IEEE.

      Recently, the U.S. Department of Energy and DARPA have launched several high-voltage grid robustness improvement projects funded by more than $3 million. Although China leads in the field of ultra-high voltage grid systems and equipment, it still needs to make up for its shortcomings in core component technology. It is worth noting that many domestic teams that were originally engaged in the research of Silicon Carbide or GaN photoconductive switches have rapidly shifted their focus to β-Ga₂O₃ high-voltage photoconductive switches. Research has been initiated by institutions such as the Institute of Semiconductors, the Tianjin XX Research Institute, the Suzhou XX Research Institute, and a certain university in Xi 'an.

      In fact, the U.S. Department of Energy laid out research on GaN ultra-high voltage optical switches between 2017 and 2023, and China has followed suit and initiated projects to support them since 2020. Several research institutes have received sufficient funding support, and the Institute of Semiconductors is one of them. Recently, Nanyang Institute of Technology and the Semiconductor Research Institute conducted in-depth research on the feasibility of >100kV ultra-high voltage β-Ga₂O₃ photoconductive switch devices based on theoretical analysis, and obtained important data in critical breakdown electric field strength, pulse energy triggering process, etc.

      The year 2025 is expected to mark the "first year" of research on Gallium Oxide 10,000-volt 1,000-ampere PCAS ultra-high voltage optical conduction auxiliary switch devices. With the continuous increase in financial support, technological breakthroughs and industrialization in this field are worth looking forward to.