Collaborative Research: Beta-Ga2O3 high voltage power MOSFETs using metal-organic chemical vapor deposition

提案标题合作研究：镓氧化物高压器件采用先进的材料生长技术的高效，智能电力电子（提案ID# 2019749/2019753）非技术摘要：电力电子是一个不可分割的组成部分，在许多应用，包括电网，电力运输，数据中心，仅举几例。它也是电动汽车、电动飞机和微电网等新兴应用的关键组件。然而，在现有的电力电子系统中，大量的能量通常被浪费为热量。超宽带隙半导体，如氧化镓（β-Ga 2 O3），可以提供高能效的电力电子产品，特别是在更高的额定电压下。由于其固有的材料特性，Ga 2 O3功率电子器件可以在更高的温度下工作，以更小的尺寸和重量处理更高的功率，同时比现有技术更高效。布法罗大学（UB）和俄亥俄州州立大学（OSU）之间的这一合作项目将解决基础科学和技术发展问题，以展示Ga 2 O 3功率晶体管。该项目将利用先进的材料生长技术沿着激进的设备设计，以实现多千伏的操作。综合教育计划旨在教育和激励学生，特别是女生和来自代表性不足群体的学生从事工程和相关领域的职业。给予本科生和研究生的研究机会将有助于培养未来劳动力的技能，从而保持美国的经济竞争力。此外，它将有助于电力电子市场的持续增长worldwide.Technical摘要：在这个合作项目中，β-Ga 2 O3的大带隙和成熟的生长技术被利用来设计、开发和演示多千伏（kV）级功率晶体管。通过金属有机化学气相沉积（MOCVD）生长的高质量β-Ga 2 O3材料与掺杂铁的电流阻挡层的实验演示一起用于设计多kV晶体管。布法罗大学的这一项目的科学目标是：（i）开发和优化电流阻挡层的铁和铬离子注入条件;（ii）设计多kV阻挡的器件和工艺流程;（iii）设计器件以消除寄生击穿并实现本征击穿能力;（iv）研究所制造器件的开关损耗;（v）使用依赖于温度的电流和电容特性来创建用于基准测试的可缩放器件模型。在俄亥俄州州立大学，目标是了解基本的MOCVD生长和β-Ga 2 O3的掺杂机制，目标是几十微米的漂移层厚度，可控的n型掺杂，特别是在低掺杂范围。具体来说，该项目旨在（i）研究杂质掺入及其与生长条件和薄膜生长速率的相关性;（ii）识别、理解和控制潜在的补偿中心，包括非本征杂质和本征点缺陷，通过全面的外延-该奖项反映了NSF的法定使命，并被认为是值得通过评估支持的使用基金会的知识价值和更广泛的影响审查标准。

Proposal TitleCollaborative Research: Gallium Oxide High-Voltage Devices Using Advanced Materials Growth Technology for Efficient, Smart Power Electronics (Proposal ID# 2019749/2019753)Non-technical Abstract:Power electronics is an integral component in many applications including the grids, electric transportation, data centers, to name a few. It is also a critical component on several emerging applications such as electric cars, electric aircraft and microgrid. However, significant energy is typically wasted as heat in the existing power electronics systems. Ultra-wide bandgap semiconductors such as gallium oxide (beta-Ga2O3) can provide energy efficient power electronics especially at higher voltage ratings. Due to their intrinsic materials properties, Ga2O3 power electronics can operate at higher temperatures, handle higher powers at reduced size, weight, and at the same time be more efficient than existing technologies. This collaborative project between the University at Buffalo (UB) and the Ohio State University (OSU) will address both fundamental science and technology development in order to demonstrate Ga2O3 power transistors. The project will utilize advanced materials growth technology along with radical device designs to achieve multi-kilovolt operation. The integrated education plan aims to educate and motivate students, especially female students and those from the underrepresented groups to pursue careers in engineering and related fields. The research opportunities given to undergraduate and graduate students will help build the skills of the future workforce, hence maintaining the economic competitiveness of the US. In addition, it will contribute to the continued growth of the power electronics market world-wide.Technical Abstract:The large bandgap of beta-Ga2O3 and the maturity of the growth technology is exploited in this collaborative project to design, develop, and demonstrate multi-kilovolt (kV) class power transistors. High quality beta-Ga2O3 material grown by metal-organic chemical vapor deposition (MOCVD) is leveraged with the experimental demonstration of the iron doped current blocking layer to design the multi-kV transistors. The scientific objectives of this project at University at Buffalo are (i) developing and optimizing iron and chromium ion implantation conditions for the current blocking layer; (ii) designing the device and process flow for multi-kV blocking; (iii) engineering the device to remove the parasitic breakdown and achieve intrinsic breakdown capability; (iv) investigating the switching losses of the fabricated devices; (v) using the temperature dependent current and capacitance characteristics to create a scalable device model for benchmarking. At Ohio State University, the objective is to understand the fundamental MOCVD growth and doping mechanisms of beta-Ga2O3 targeting for drift layer thicknesses of tens of micrometers with controllable n-type doping, especially in the low doping range. Specifically, this project aims to (i) study the impurity incorporation and its correlation with the growth condition and film growth rate; (ii) identify, understand, and control potential compensation centers, including extrinsic impurities and intrinsic point defects, through comprehensive epitaxial-layer characterization and feedbacks from device characterization.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.