Ultra-widebandgap Ga2O3 power devices for next generation power electronics

与笔记本电脑和智能手机中的电子产品不同，电力电子产品控制和处理电力流动。电力电子是将风能、太阳能和地热等可再生能源整合到未来能源电网中以保障能源和环境安全的使能技术。此外，电力电子在节能电动汽车和混合动力汽车中也发挥着关键作用。电力电子学的核心是一个功率晶体管，它可以开关电源。在这个过程中，能量以热的形式损失。宽带隙半导体使新的电力电子技术成为可能，与现有的硅基技术相比，这种技术可以显著降低能量损耗。研究了一种新型宽带隙半导体材料--氧化镓，以实现高效的电力电子学。这种新型宽带隙半导体的基本性质将用先进的科学方法来探索。还将开展研究，以开发一种改变半导体电导率的技术，这是制造功率晶体管所必需的。这些研究也将加深对宽带隙半导体在其他领域有潜在应用的了解。除了材料性能外，还将对晶体管进行电气测试，以评估功率晶体管的速度。该项目将使美国处于电力电子创新的前沿，并推动最近电力电子行业的持续增长，对美国经济产生积极影响。由于高效的切换和减少温室气体排放，美国的环境和能源安全将得到加强。为本科生和研究生提供的研究机会将有助于培养未来劳动力的技能，以适应知识经济，并保持美国的经济竞争力。研究工作将与针对本科生、高中生和理工科代表不足的学生的教育推广活动相结合。它将增加少数族裔和妇女在科学和工程领域的参与，提高美国在科学和工程领域的竞争力。该提案的目标是从根本上低估新兴的氧化镓宽带隙半导体的材料性能，并开发一种高压功率晶体管。我们将研究离子注入的N型掺杂和隔离掺杂。掺杂薄膜将通过先进的材料表征技术进行表征，包括二次离子显微镜(SIMS)、卢瑟福背散射(RBS)以及电学测试结构。掺杂技术使功率晶体管中电场分布的工程能够提高击穿电压。此外，还将对电子传输特性和界面电学特性进行表征。在基础研究的基础上，将制造出高压功率晶体管。功率晶体管的开关速度将用双脉冲方法来表征。这些研究将促进对宽带隙半导体性质的理解。此外，还可以将该技术与其他宽带隙半导体进行准确的比较。

Power electronics, in contrast to the electronics in laptops and smart phones, controls and handles the flow of power. Power electronics is the enabling technology for integration of renewable energy sources such as wind, solar, and geothermal to the future energy grid for both energy and environmental security. In addition, power electronics has a critical role in power efficient electric and hybrid cars. At the heart of power electronics is a power transistor that switches the power on and off. Energy is lost as heat during this process. Widebandgap semiconductors enable new power electronics technology that can significantly reduce the energy losses than the present silicon based technology. A new widebandgap semiconductor, gallium oxide, is investigated here for efficient power electronics. The fundamental properties of this novel widebandgap semiconductor will be explored using advanced scientific methodology. Studies will also be carried out to develop a technology to change the electrical conductivity of the semiconductor, which is essential to building the power transistor. These studies will also increase the understanding of the widebandgap semiconductor that have potential application in other fields. In addition to the materials properties, electrical testing of the transistors will be carried out to evaluate the speed of the power transistors.This project will position US at the forefront of power electronics innovation and propel the recent continued growth of the power electronics industry with positive outcomes on the US economy. The environmental and energy security of US will be enhanced due to high efficiency in switching and reduced greenhouse gases. The research opportunity given to undergraduate and graduate students will help build the skills of the future workforce for knowledge based economy and maintain the economic competitiveness of the US. The research effort will be integrated with educational outreach activities for undergraduates, high-school students and under-represented students in science and engineering. It will increase the participation of underrepresented minority and women in the field of science and engineering enhancing US competitiveness in science and engineering.The objectives of the proposal is to develop a fundamental understating of the materials properties of the emerging gallium oxide widebandgap semiconductor and develop a high voltage power transistor. N-type doping and isolation doping by ion-implantation will be investigated. The doped films will be characterized by advanced materials characterization techniques including secondary ion microscopy (SIMS), Rutherford backscattering (RBS) and also by electrical test structures. The doping technology enables the engineering of the electric field profile in the power transistor to increase the breakdown voltage. In addition the electron transport properties and interface electrical properties will be characterized. Building upon the fundamental studies, high voltage power transistors will be fabricated. The switching speed of the power transistors will be characterized by double pulse method. These studies will be advance the understanding of the widebandgap semiconductor properties. In addition, an accurate comparison of the technology with other widebandgap semiconductors can be made.