Vibrational spectroscopy of Ga+ ion implanted ta-C films

INERA Conference 2015: Light in Nanoscience and Nanotechnology

Berova, M.^1 ; Sandulov, M.^1 ; Tsvetkova, T.^1 ; Bischoff, L.^2 ; Boettger, R.^2 ; Abrashev, M.^3

Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee, Sofia

1784, Bulgaria^1

Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden- Rossendorf, P. O. B. 51 01 19, Dresden

01314, Germany^2

Faculty of Physics, Sofia University, Sofia

1164, Bulgaria^3

关键词: Filtered cathodic vacuum arc;    High density optical data storage;    Optical absorption edge;    Optical transmission measurements;    Photo darkening effects;    Structural and optical properties;    Structural modifications;    Tetrahedral amorphous carbon (ta-C);   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/682/1/012020/pdf
DOI  :  10.1088/1742-6596/682/1/012020

来源: IOP

【 摘 要 】

In the present work, low energy Ga+ ion beam implantation was used for the structural and optical properties modification of tetrahedral amorphous carbon (ta-C) thin films, using gallium (Ga+) as the ion species. Thin film samples (d∼40nm) of ta-C, deposited by filtered cathodic vacuum arc (FCVA), have been implanted with Ga+at ion energy E = 20 keV and ion doses D=3.10143.1015cm-2. The Ga+ ion beam induced structural modification of the implanted material results in a considerable change of its optical properties, displayed in a significant shift of the optical absorption edge to lower photon energies as obtained from optical transmission measurements. This shift is accompanied by a considerable increase of the absorption coefficient (photo-darkening effect) in the measured photon energy range (0.53.0 eV). These effects could be attributed both to additional defect introduction and increased graphitisation, as well as to accompanying formation of bonds between the implanted ions and the host atoms of the target, as confirmed by infra-red (IR) and Raman measurements. The optical contrast thus obtained (between implanted and unimplanted film material) could be made use of for information archiving, in the area of high-density optical data storage, while using focused Ga+ion beams.