【Expert Interview】Zhang Hui, Chairman of Hangzhou GAREN SEMI Co., LTD., a Gallium Oxide Technology Enterprise/Professor of Zhejiang University: In the Future, the Large-Cale Application of Gallium Oxide may be Realized First in the Field of Power Devices

      In recent years, with the support and promotion of international pressure and government funding and other incentives, a large number of excellent and professional compound semiconductor teams and startups have emerged in China. Due to the strong telecom and automotive industries, supply chain opportunities have driven the compound semiconductor market to become increasingly hot, achieving rapid growth and technological breakthroughs. According to the report, the global semiconductor market size is expected to increase from US $627.76 billion in 2025 to about US $1,137.57 billion in 2033.

      What are the development prospects of the compound semiconductor industry in 2025? What breakthroughs or innovations can be expected in the New Year? How to deal with the geopolitical impact on the industry and solve technical bottlenecks? What should we do to drive the market in the future? ... These are of great concern to the industry. Compound Semiconductors magazine has a special "Outlook 2025" interview, inviting industry experts and company executives to share their insights and analysis on these industry issues. We interviewed Zhang Hui, chairman of Hangzhou GAREN SEMI Co., Ltd. and professor of Zhejiang University, to share his unique insights.

Interview Guest

Zhang Hui

Chairman of Hangzhou GAREN SEMI Co., LTD. / Professor of Zhejiang University

      Professor Zhang Hui is the chairman of Hangzhou GAREN SEMI Co., LTD., a dual professor and doctoral supervisor of the National Key Laboratory of Silicon and Advanced Semiconductor Materials of Zhejiang University and the Advanced Semiconductor Research Institute of ZJU-Hangzhou Global Scientific and Technological Innovation Center. To meet the urgent demand of power device materials, the melt growth, defect control, crystal processing and doping of Gallium Oxide single crystal materials have been studied. He has published a series of papers in internationally renowned journals such as Chem. Soc. Rev., J. Am. Chem. Soc., Nano Lett., Adv. Mater., Angew. Chem. Int.Ed., etc. In 2007, he was nominated for one hundred outstanding doctoral dissertations in China, in 2008, he won the first prize of Science and Technology of Zhejiang Province (ranked third), and in 2013, he won the second prize of National Natural Science (ranked second). In 2014, he was selected into the Ten-Thousand Talents Program. In 2015, he was awarded the National Natural Science Foundation--Outstanding Youth Foundation.

Hangzhou GAREN SEMI Co., LTD

      Hangzhou GAREN SEMI Co., LTD., founded in September 2022 and located in Xiaoshan District, Hangzhou City, Zhejiang Province, is a scientific and technological enterprise focusing on R&D, production and sales of Gallium Oxide materials and Gallium Oxide special crystal growth equipment for ultra-wide band gap semiconductors. Relying on the National Key Laboratory of Silicon and Advanced Semiconductor Materials of ZJU-Hangzhou Global Scientific and Technological Innovation Center, GAREN SEMI has built a research and development, production and operation team with academicians of Chinese Academy of Sciences as the chief consultant and rich industry experience.

Questions & Answers

CSC: In recent years, Gallium Oxide, Aluminum Nitride, Diamond and Boron Nitride, as ultra-wide band gap materials, have attracted much attention from the academic community and gained great favor in the industry in China and Japan. What is your opinion on the development of ultra-wide band gap materials related technologies and future industrialization, and what are the most likely application scenarios?

      As an ultra-wide band gap semiconductor material, Gallium Oxide is the focus of competition in many countries in recent years. The United States and Japan have implemented an embargo policy on China's Gallium Oxide materials, making it a "jam neck" material in the wide band gap semiconductor field, but at the same time, it also provides development opportunities for China's Gallium Oxide industry, prompting domestic enterprises to accelerate independent research and development and innovation.

      At present, Gallium Oxide is the only ultra-wide band gap semiconductor material that can be mass-produced by Flux method. It is mainly used in power devices, radio frequency devices, and solar blind detector. Gallium Oxide has the advantages of large bandgap, high breakdown electric field and high BFOM, which make the power devices based on Gallium Oxide have larger working current, voltage, smaller on-resistance, device size and higher conversion efficiency, and have outstanding advantages in the production of high-performance power devices. Therefore, it is possible to realize the large-scale application of Gallium Oxide in the field of power devices in the future.

      The common growth processes of Gallium Oxide single crystal include: EFG method, Casting method, Vertical Bridgman method, Czochralski process, Cold Crucible method and Optical Floating Zone method. Among them, the EFG method, Casting method and Vertical Bridgman method have been able to grow Gallium Oxide single crystal with a diameter of 6 inches, which is the most expected to achieve industrial large-scale production. Czochralski method has special advantages in the preparation of large size (010) substrate, and the largest size in the world has reached 3 inches. The advantage of Cold Crucible method and Optical Floating Zone method is that there is no need for precious metal crucible, which can greatly reduce the cost of single crystal growth, of which the Cold Crucible method can already grow 2 inches of single crystal. In the above growth process, the Vertical Bridgman (VB) method has significant advantages in the growth of Gallium Oxide single crystal, and is becoming the new favorite of the industry, and Gallium Oxide substrate manufacturers in domestic and international have begun to accelerate the layout. GAREN has taken the lead in completing the verification of 4-inch VB Gallium Oxide long crystal equipment and process package in China, and is fully open for sale, and helps the scientific research and industrial development of Gallium Oxide materials.

      In the past three years, the Gallium Oxide industry chain is gradually complete, among which the substrate and epitaxial development is particularly rapid, and will soon run with foreign head enterprises, or even lead, which will greatly speed up the process of domestic device industrialization.