Back to Search
Start Over
Piezoresistive Ni:a-C:H thin films containing hcp-Ni or Ni3C investigated by XRD, EXAFS, and wavelet analysis.
- Source :
-
Diamond & Related Materials . Apr2013, Vol. 34, p25-35. 11p. - Publication Year :
- 2013
-
Abstract
- Abstract: Ni:a-C:H thin films obtained by reactive sputtering processes were investigated using EXAFS and subsequent wavelet analysis. Depending on overall thin film deposition conditions, the clusters of Ni in Ni:a-C:H can appear as fcc-Ni or as a non-fcc-Ni phase, such as hcp-Ni or Ni3C. While hcp-Ni and Ni3C are hardly distinguishable by XRD, the EXAFS analysis can reveal if carbon is the nearest neighbour of Ni or not, thus if Ni3C is present or hcp-Ni. Our study showed that wavelet transformation analysis of the EXAFS data is necessary to discriminate clearly between hcp-Ni and Ni3C regarding the presence or absence of carbon coordination shells around the X-ray absorbing Ni atoms. Furthermore, we are confident to have identified Ni3C in our thin films, however, we cannot exclude the possibility of the co-existence of hcp-Ni. Finally, calculations of XRD peaks of hcp-Ni and Ni3C showed that a discrimination of these two crystal phases might be feasible when the crystallite size is increased beyond 40nm. [Copyright &y& Elsevier]
Details
- Language :
- English
- ISSN :
- 09259635
- Volume :
- 34
- Database :
- Academic Search Index
- Journal :
- Diamond & Related Materials
- Publication Type :
- Academic Journal
- Accession number :
- 89159403
- Full Text :
- https://doi.org/10.1016/j.diamond.2013.01.013