| AVS 56th International Symposium & Exhibition | |
| Electronic Materials and Processing | Tuesday Sessions |
| Session EM-TuP |
| Session: | Electronic Materials and Processing Poster Session |
| Presenter: | M. Lejeune, LPMC - UPJV, France |
| Authors: | F. Alibart, LPMC - UPJV, France O. Durand-Drouhin, LPMC - UPJV, France A. Zeinert, LPMC - UPJV, France M. Benlahsen, LPMC - UPJV, France M. Lejeune, LPMC - UPJV, France |
| Correspondent: | Click to Email |
In this study, we discuss the correlations between electrical and optical properties of highly sp² amorphous carbon nitride for the development of electronic devices applications. The amorphous carbon thin films have been deposited using reactive plasma (Ar+N2) radio frequency magnetron sputtering. The partial pressure of nitrogen has been used to vary the optoelectronics properties of the films.
The optical gap has been investigated using UV-visible-NIR spectroscopy and linked to the disorder parameter W-1. The electrical conductivity has been studied in the temperature range of -170°C to 300°C and has revealed the presence of two conductivity modes. These results have been interpreted as a function of the density of states (DOS) evolution. The microstructural evolutions of the films with nitrogen incorporation have been investigated by Raman spectroscopy and IR absorption spectroscopy.
The disorder parameter W-1 has shown a linear dependence with the optical gap in this range of materials (highly sp² carbon films) and has been interpreted as a measure of the overall disorder (structural and topological). At low nitrogen partial pressure, nitrogen incorporation promotes the graphitization and the clustering of the sp² phase. The preferential contribution of disorder has been identified as an increase of topological disorder (cluster size dispersion). The increase of electrical conductivity in this stage has been correlated to the increase of disorder and has revealed an increase of the sp² connectivity consistent with an increase of the cluster size.
The decrease of conductivity for the higher nitrogen content has been interpreted in a specific model for highly sp² materials (adaptation of Robertson’s two phase model). The proportion of CN triple bonds has been identified as a major effect on the material connectivity affecting the optoelectronic properties of the films.