Group IV Semiconductors Derived From Zintl Phases

NON-TECHNICAL SUMMARY

This project, jointly funded by the Solid State and Materials Chemistry program in the Division of Materials Research and the Established Program to Stimulate Competitive Research (EPSCoR), focuses on developing extremely thin layered semiconductor materials with precise control over the arrangement of atoms in the material, on the surfaces of each layer, and the gaps between the layers. This level of control is expected to result in control over the material's optical properties, which could enable new technologies like integrated photonic circuits that use light to transport data and chips instead of electricity.

Integrated photonic circuits have the potential to result in computers and mobile phones that use much less electricity and operate faster. The research is expected to advance fundamental knowledge in materials chemistry, nanotechnology, and semiconductors. It explores approaches to gaining atomically precise control over the structure of layered semiconductors, which can potentially lead to new synthetic methods for creating layered materials with properties that could benefit many different applications.

The societal benefits of this project are broad ranging. Light-emitting semiconductors made from silicon and germanium can enable faster and more efficient computing that can substantially impact energy usage and also have the potential to enable new types of information technology like quantum computing. The materials are expected to have properties that will make them useful for applications outside of information science, like sensing and energy storage.

The project also integrates the education and training of educators and students at regional high schools, community colleges, and public universities to broaden the participation of groups traditionally underrepresented in the technical workforce. The integrated educational plan gives this project a broad societal impact that addresses technological needs for a sustainable future and also prepares the future workforce to advance national security, prosperity, and national health.

TECHNICAL SUMMARY

Integrating light-emitting components into microelectronic circuits has been a technological challenge due to stringent optical, electronic, and chemical requirements. The main goal of this project is to demonstrate a family of layered Group IV semiconductors with properties that meet these requirements. These layered Group IV semiconductors are derived from Zintl phases and have properties that could enable energy-efficient, ultrafast "integrated photonic" circuits.

The goals of this project are to (1) synthesize layered silicon-germanium alloy semiconductors with controlled composition, structure, and surface chemistry, (2) determine how structure and chemistry influence optoelectronic properties using experimental characterization and density functional theory, and (3) characterize their thermal and environmental stability to assess their potential for real-world applications. Zintl phases comprised of atomically thin silicon-germanium alloy sheets separated by alkali metal ions or salts will be synthesized.

The Zintl phases compounds will be deintercalated into multilayer semiconductors comprised of atomically thin sheets, with surfaces that can be functionalized to passivate surfaces and control their properties. In addition to computing, these materials are expected to have chemical and optoelectronic properties that could benefit numerous applications such as computing, sensing, and quantum information science.

Integrated with the research are plans to work with high school STEM teachers and the NSF-funded IINSPIRE-LSAMP alliance to expand the future workforce by increasing participation of underrepresented groups and improving students' preparedness to contribute to advancing technologies that are important for national security, prosperity, and national health.

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.