MRI: Acquisition of a NanoRaman Atomic Force Microscopy (AFM) System for Multi-Property Measurements in Electronic and Other Materials

Non-Technical Description:

This major research instrumentation award supports the acquisition of a NanoRaman AFM (atomic force microscopy) system at Northwestern University (NU). The instrument integrates scanning probe microscopy (SPM) for measurements of nanoscale material properties (topography, friction, surface potential, electrical and thermal conductivity, etc.) with optical spectroscopy tools including confocal Raman, tip-enhanced Raman (TERS), and photoluminescence (TEPL) spectroscopy.

The instrument enables correlated multi-property measurements of structural, physical, and chemical properties of nanoscale materials by researchers from broad backgrounds at NU including, Mechanical Engineering, Civil and Environmental Engineering, Materials Science and Engineering, Chemistry, and Earth and Planetary Sciences, and users outside of NU. The instrument facilitates the discovery of new electronic materials and the development of novel devices that range from transistors, photodetectors to advanced brain-inspired computing technologies.

In addition, the instrument is integrated into existing graduate and undergraduate curricula at NU to facilitate hands-on experimentation of the multi-physics of nanoscale materials. The instrument also provides opportunities for educating the next generation of nano-scientists and engineers and diversifying the Nation's STEM workforce through multidisciplinary training for underrepresented students at grade school, undergraduate, and graduate levels.

Technical Description:

The NanoRaman AFM system offers a versatile platform for correlated multi-property measurements with 10 nm lateral spatial resolution and high measurement precision. The instrument facilitates integrating multi-dimensional electronic materials to leverage interfaces and defects to enable novel electronic, optoelectronic, and thermoelectric phenomena.

Through SPM, TERS, TEPL, and second harmonic generation measurements, the instrument allows studies of thermal, mechanical, electronic, and optical properties in mixed-dimensional heterostructures and how defects can control these properties. Specifically, researchers use the instrument to characterize carrier concentration and band-edge energy modulation in low-dimensional ferroelectrics with polarizable nanoscale domains, heat dissipation across individual grain boundaries and defects in 2D semiconducting crystals, excitonic and nonlinear optical properties emissions in 2D van der Waals crystals coupled to plasmonic lattices, and local studies of photophysical phenomena in perovskite compounds that impact the performance of electronic devices.

In addition, this instrument facilitates measurements outside the scope of electronic materials. Scientists study, for example, soil and sedimentary organics at microscale and nanoscale interfaces for carbon sequestration applications, tunable metal-organic frameworks for chemical sensing, and nanoscale composite materials for enhanced performance of construction materials.

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.