Spectroscopy and structural properties of amorphous and nanocrystalline silicon carbide thin films

Abstract

Amorphous SiC:H thin films were grown by hot wire chemical vapour deposition from a SiH4/CH4/H2 mixture at a substrate temperature below 400 °C. Thermal annealing in an argon environment up to 900 °C shows that the films crystallize as μc‐Si:H and SiC with a porous microstructure that favours an oxidation process. By a combination of spectroscopic tools comprising Fourier transform infrared, Raman scattering and X‐rays photoelectron spectroscopy we show that the films evolve from the amorphous SiHx/SiCH2 structure to nanocrystalline Si and SiC upon annealing at a temperature of 900 °C. A strong RT photoluminescence peak of similar shape has been observed at around 420 nm in both as‐deposited and annealed samples. Time‐resolved luminescence measurements reveal that this peak is fast decaying with lifetimes ranging from 0.5 to ∼1.1 ns. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Direct Writing of Fluorescent Semiconducting Nanoparticles on Polydimethylsiloxane by Ultrashort-Pulsed Laser Processing: Implications for Electronic and Photonic Device Fabrication

“…Such asymmetric broadening, particularly for lower frequencies, has been associated with the formation of SiC-NCs from amorphous SiC precursors. 37 Moreover, with an increase in PE, the Si−C bond peak became increasingly broad, suggesting an increase in the polydispersity of the SiC-NCs, consistent with the TEM results (Figure 5i). Furthermore, the intensity of the Si−O bond peak decreased as the PE increased, implying that products formed with higher PEs, including SiC-NCs, possess significantly lower amounts of oxygen-containing functional groups.…”

“…Particularly, the Si–C bond peak is significantly broadened for the structures compared to PDMS (Figure b). Such asymmetric broadening, particularly for lower frequencies, has been associated with the formation of SiC-NCs from amorphous SiC precursors . Moreover, with an increase in PE, the Si–C bond peak became increasingly broad, suggesting an increase in the polydispersity of the SiC-NCs, consistent with the TEM results (Figure i).…”