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The semiconductor and optical properties of UO2 are investigated. The very long drift carrier lifetimes, obtained from current-voltage I(V) and capacitance-voltage C(V) measurements, along with the well-defined optical properties provide little evidence of an abundance of material defects away from the surface region. Schottky barrier formation may be possible, but very much dependent on the choice of contact and surface stoichiometry and we find that Ohmic contacts are in fact favored. Depth resolved photoemission provided evidence of a chemical shift at the surface. Density functional theory, with the Heyd-Scuseria-Ernzerhof (HSE) functional, indicates a band gap of a 2.19 eV and an anti-ferromagnetic ground state. Ellipsometry measurements indicates at UO2 is relatively isotropic with a band gap of approximately 2.0 eV band gap, consistent with theoretical expectations.

Plasma-enhanced chemical vapor (PECVD) codeposition of benzene and 1,2-dicarbadodecaborane, 1,2-B10C2H12 (orthocarborane) and benzene, 1,7 dicarbadodecaborane, and 1,7-B10C2H12 (metacarborane) results in semiconducting boron carbide composite films with significantly longer drift carrier lifetimes than plasma-enhanced chemical vapor deposited semiconducting boron carbide synthesized from orthocarborane or metacarborane alone. Capacitance versus voltage C(V) and current versus voltage I(V) measurements indicate the hole carrier lifetimes for PECVD benzene/orthocarborane based semiconducting boron carbide composites increase to 2.5 ms from values of ≤35 μs for the PECVD semiconducting boron carbide films fabricated without benzene. For PECVD benzene/metacarborane based semiconducting boron carbide composites, there is an increase in the hole carrier lifetime to roughly 300 ns from values of 50 ns for those films fabricated without benzene.

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Amorphous hydrogenated boron carbide films (a-B 10 C 2+x :H y) on Si p-n heterojunctions were fabricated utilizing plasma enhanced chemical vapor deposition (PECVD). These