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Schulz, Douglas L.

Publications and source records attributed to Schulz, Douglas L..

Solution-Based Synthesis of Crystalline Silicon from Liquid Silane through Laser and Chemical Annealing

We report a solution process for the synthesis of crystalline silicon from the liquid silane precursor cyclohexasilane (Si 6 H 12 ). Polysilane films were crystallized through thermal and laser annealing, with plasma hydrogenation at atmospheric pressure generating further structural changes in the films. The evolution from amorphous to microcrystalline is characterized using scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman spectroscopy and impedance spectroscopy. A four-decade enhancement in the electrical conductivity is attributed to a disorder-order transition in a bonded Si network. Lastly, our results demonstrate a potentially attractive approach that employs a solution process coupled with ambient post-processing to produce crystalline silicon thin films.

36 MATERIALS SCIENCE↗

Work function characterization of solution-processed cobalt silicide

Cobalt silicide thin films were prepared by spin-coating Si6H12-based inks onto various substrates followed by a thermal treatment. The work function of the solution processed Co-Si was determined by both capacitance-voltage (C-V) measurements of metal-oxide-semiconductor (MOS) structures as well as by ultraviolet photoelectron spectroscopy (UPS). The UPS-derived work function was 4.80 eV for a Co-Si film on Si (100) while C-V of MOS structures yielded a work function of 4.36 eV where the metal was solution-processed Co-Si, the oxide was SiO2 and the semiconductor was a B-doped Si wafer.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗