CAREER: van der Waals Semiconductor Integration via Surface and Interface Tailoring

职业：通过表面和界面定制进行范德华半导体集成

• 批准号: 2238564
• 负责人: Sidong Lei
• 金额: $ 51.61万
• 依托单位: Georgia State University Research Foundation, Inc.
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-01 至 2028-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2238564&HistoricalAwards=false
• 关键词: CAREER; van; der; Waals; Semiconductor

As the post-10 nm era approaches, further shrinking of silicon microelectronics turns out to be more difficult and less beneficial. Instead, van der Waals semiconductors (vdW-S) with atomic thickness become the leading candidates to further boost the trajectory of Moore’s law. After the successful synthesis of wafer-scale raw materials, the next milestone on this roadmap is the implementation of vdW-S integrated circuits with smaller sizes, higher density, faster speed, and lower energy consumption. However, established methods for bulk material integration, such as silicon, lead to performance degradation, high heat generation, and many other issues in vdW-S. Therefore, new fundamental principles and practical methods are in urgent need, and this project is designed to fill this gap. Considering the ultra-thinness of these emerging materials, their electronic properties are typically decided by the surface and interfacial conditions. With this entry point, the project makes efforts to explore surface/interface tailoring methods and study the corresponding electronic effects for the purpose of vdW-S integration in both planar and three-dimensional (3D) configurations. As a case study, a novel 3D active pixel image sensor (3D-APS) built upon the as-developed principles can provide better color-sensing accuracy, miniature device size, and higher sensitivity than conventional counterparts. As such, it showcases the transformative impacts of this project on a broader scope of applications, such as medical imaging, machine vision, and environmental survey. Along with the research, this project emphasizes the educational responsibility, especially for the underrepresented minority groups in science, technology, engineering, and mathematics, leveraging the advanced status of Georgia State University (GSU) as a minority-serving institute. Graduate and undergraduate students, particularly minority students, receive systematic training in modern material science, electrical engineering, semiconductor process and characterization technologies, instrumentation design and manufacturing, and many more skills. In this process, they build their capabilities and career trajectories as next-generation workforces. The team shares the research experience and achievements via seminars, conferences, and publications, to bring nationwide impacts of this project. Regular open houses, K-12 school visits, and popular science activities are arranged to broadcast the latest research progress to our community, raising public awareness of modern science and technology. The very large-scale integration (VLSI) of vdW-S devices is the next essential topic for their practical applications in computing, communication, medication, and other fields. But the long-standing challenges in selected area doping, contact resistance management, material stability, and characterization methods block the pathway toward these goals. In this regard, this project is arranged to systematically and profoundly investigate the solutions to these problems, and substantially promote the planar and 3D integration of these emerging semiconductor materials. The primary research activities include the following aspects. (i) The project insightfully comprehends the charge doping effects and stability of a surface modification reaction introduced by the PI, in order to facilitate a gentle, precisely controllable, and non-destructive selected area doping approach for planar vdW-S integration. (ii) Conventional metal-to-vdW-S inter-tier contacts are replaced by newly developed direct vdW-S-to-vdW-S (v-v) contacts with conditioned interfaces, which provide a scalable and low-resistance solution for inter-tier connections in 3D integrations. (iii) The research activities leverage the home-built in-situ and non-invasive electrical and optical characterization systems to examine the devices’ stability and performance with convinced accuracy and precision. Beyond that, the 3D-APS delivered by this project can exhibit rich system-level physical and electronic behaviors that otherwise are intangible from single device-level studies, and in turn, deepen the understanding of the synergistic cooperation mechanism in complex vdW-S frameworks. The prototype devices also inspire succeeding innovations of high-performance microelectronics, as core functional units in future VLSI with smaller sizes, higher integration density, faster speed, and lower energy consumption.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.

随着后10纳米时代的临近，硅微电子的进一步缩小变得更加困难，也更没有好处。相反，具有原子厚度的货车范德华半导体（vdW-S）成为进一步推动摩尔定律轨迹的主要候选者。在成功合成晶圆级原材料之后，该路线图的下一个里程碑是实现更小尺寸、更高密度、更快速度和更低能耗的vdW-S集成电路。然而，已建立的用于体材料集成（例如硅）的方法导致vdW-S中的性能退化、高发热和许多其他问题。因此，迫切需要新的基本原理和实用方法，本项目旨在填补这一空白。考虑到这些新兴材料的超薄性，它们的电子特性通常由表面和界面条件决定。有了这个切入点，该项目努力探索表面/界面剪裁方法，并研究相应的电子效应，以实现平面和三维（3D）配置中的vdW-S集成。作为一个案例研究，一种新型的3D有源像素图像传感器（3D-APS）建立在所开发的原则，可以提供更好的颜色传感精度，微型设备的尺寸，和更高的灵敏度比传统的同行。因此，它展示了该项目对更广泛应用的变革性影响，如医学成像，机器视觉和环境调查。沿着研究，该项目强调教育责任，特别是对科学，技术，工程和数学代表性不足的少数群体，利用格鲁吉亚州立大学（GSU）作为少数民族服务机构的先进地位。研究生和本科生，特别是少数民族学生，接受现代材料科学，电气工程，半导体工艺和表征技术，仪器设计和制造以及更多技能的系统培训。在这个过程中，他们建立自己的能力和职业轨迹作为下一代劳动力。该团队通过研讨会，会议和出版物分享研究经验和成果，以使该项目在全国范围内产生影响。我们定期安排开放日、K-12学校参观和科普活动，向社区传播最新的研究进展，提高公众对现代科学和技术的认识。vdW-S器件的超大规模集成（VLSI）是其在计算、通信、医学和其他领域的实际应用的下一个重要课题。但是，在选定区域掺杂、接触电阻管理、材料稳定性和表征方法方面的长期挑战阻碍了实现这些目标的途径。因此，本项目旨在系统深入地研究这些问题的解决方案，并实质性地促进这些新兴半导体材料的平面和3D集成。主要研究活动包括以下几个方面。(i)该项目深入研究了PI引入的表面改性反应的电荷掺杂效应和稳定性，以促进平面vdW-S集成的温和，精确可控和非破坏性的选区掺杂方法。(ii)传统的金属到vdW-S层间接触被新开发的具有调节界面的直接vdW-S到vdW-S（v-v）接触所取代，这为3D集成中的层间连接提供了可扩展的低电阻解决方案。(iii)研究活动利用自制的原位和非侵入性电气和光学表征系统，以确信的准确性和精度检查设备的稳定性和性能。除此之外，该项目提供的3D-APS可以表现出丰富的系统级物理和电子行为，这些行为在单个设备级研究中是不可见的，从而加深了对复杂vdW-S框架中协同合作机制的理解。该原型器件还激发了未来超大规模集成电路（VLSI）的核心功能单元--高性能微电子的后续创新，这些功能单元具有更小的尺寸、更高的集成密度、更快的速度和更低的能耗。该奖项反映了NSF的法定使命，通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。