Original scientific paper
Structural properties of a-Si1-xCx:H by SAXS and IR spectroscopy
Davor Gracin
; "R. Bošković" Institute, POB 1016, Bijenička 54, 10000 Zagreb, Croatia
Pavo Dubček
; "R. Bošković" Institute, POB 1016, Bijenička 54, 10000 Zagreb, Croatia
Abstract
The a-Si1-xCx:H thin films, with carbon concentrations up to x = 0.3 deposited by means of a DC magnetron sputtering source, using benzene vapour as the origin of carbon atoms, were analysed by small-angle X-ray scattering (SAXS) and IR spectroscopy. The incorporation of carbon atoms in a-Si:H results in the appearance of IR absorption related to the Si-C and C-H bonds and a slight decrease of absorption related to Si-H bonds. By increasing the carbon concentration, stretching frequency of Si-H bonds increases. This frequency, which is related to the described changes, is considered to be the consequence of an increasing void volume ratio and/or void volume per each Si-H oscillator. The SAXS data of pure a-Si:H indicate ``particles" with the giro radius RG = 1.27 nm, which increases with the carbon content up to RG = 2.05 nm. These ``particles" are attributed to the clusters of small voids with dimensions up to several silicon vacancies.
Keywords
a-Si1-xCx:H thin films; different carbon concentrations; DC magnetron sputtering; small angle X-ray scattering (SAXS); IR spectroscopy; stretching frequency of Si-H bonds; clusters of small voids
Hrčak ID:
300966
URI
Publication date:
1.7.1999.
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