Abstract

The network disorder of a-Si 1− x C x :H films containing carbon concentrations below 20 at.% has been studied by means of Raman spectroscopy and photoluminescence (PL) measurements. Two different radiations were employed to excite these materials, one higher than the optical gap and strongly absorbed (488 nm), the other near to the optical gap and weakly absorbed (647.1 nm). When excited with strongly absorbed radiation, the frequency and width of TO mode have a large redshift and broadening relative to the weakly absorbed radiation, while the position and width of PL peak have a blueshift plus broadening. The variations in probed depth together with the significant differences observed in the Raman spectra and PL spectra indicate the existence of two types of inhomogeneities: a highly disordered thin layer near free surface and gap fluctuations due to spatial variations of compositions in the bulk. The above results indicate that Raman and PL characteristics at different radiations can be used to explore the spatial variations of materials.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.