Ultra-wide bandgap semiconductors are candidate materials for next generation high power, and high efficiency radio frequency applications. Among the most promising are AlN, Ga2O3, diamond, and cubic BN.  In order to realize these materials and replace existing technologies we must develop and understand their atomic structure.  NRL has world class MBE and MOCVD reactors and growth teams, and this research opportunity would be to study these NRL made materials using advanced electron microscopy.  Our objective is to provide nanoscale characterization of the phases, interfaces, and defect microstructure of epitaxial heterostructures. At NRL we have traditional sample preparation facilities, including a Thermo Fischer Helios G3 FIB, low kV Ar ion milling, and multiple transmission electron microscopes including a JEOL F200 equipped with a continuum spectrometer, dual EDS, 4D-STEM, and IDES dose control system, and an aberration corrected Nion UltraSTEM 200X equipped with EDS and a MerlinEM direct electron detector for EELS analysis.  Ideal applicants will have experience and interest doing advanced electron energy-loss spectroscopy, high resolution imaging, 4D-STEM, and python-based data analysis.

Examples of relevant work from NRL: 

DF Storm et al. Phys. Status Solidi RRL 2022, 16, 2200036 "Mg-Facilitated Growth of Cubic Boron Nitride by Ion Beam-Assisted Molecular Beam Epitaxy" 

VD Wheeler et al. Chemistry of Materials 2020 32 (3), 1140-1152 "Phase Control of Crystalline Ga2O3 Films by Plasma-Enhanced Atomic Layer Deposition"

key words

Transmission Electron Microscopy, 4D STEM, Ultrawide Bandgap Semiconductors, Electron Energy Loss Spectroscopy, III-Nitrides, Semiconductor Characterization,

Citizenship:  Open to U.S. citizens and permanent residents

Level:  Open to Postdoctoral applicants