ORALS
SESSION: ManufacturingTueAM-R4
Non-Ferrous Advanced Materials from Macro- to Nanoscale – I | Mamalis International Symposium on Advanced Manufacturing of Advanced Materials and Structures with Sustainable Industrial Applications |
| Tue Nov, 6 2018 / Room: Sao Conrado (50/2nd) | |
| Session Chairs: Mustafa Guden; Session Monitor: TBA |
12:10: [ManufacturingTueAM03]
Structure and Optical Properties of Nanocomposite Carbon Films Obtained from Accelerated C60 Ion Flows Svetlana
Rudchenko
1 ; Vladimir Egorovich
Pukha
1 ; Vadym V.
Starikov
1 ;
Athanasios G.
Mamalis2 ; Sergiy N.
Lavrynenko
3 ;
1National Technical University - Kharkov Polytechnic Institute, Kharkiv, Ukraine;
2PC-NAE, Demokritos National Center for Scientific Research, Athens, Greece;
3Kharkov Polytechnic Institute, Kharkov, Ukraine;
Paper Id: 151
[Abstract] The results of structural and optical investigations of thin carbon films deposited from the mass-separated beam of accelerated C60 ions with energy of 5 keV are presented. The substrate temperature ranged from 100°C to 400°C. It was established that change of the TS from 100°C to 400°C leads to the consecutive formation of diamond-like carbon (DLC) films with amorphous state and superhard nanocomposites consisting nanographite structures (1-2 nm) surrounded by a diamond-like amorphous matrix. For amorphous films the band gap (Eg) was in the range of 1.2 - 1.4 eV. For nanocomposite films on optical absorption spectra, there are two energy components: one with a narrow Eg = 1 eV, which is associated with three-dimensional nanocrystals of graphite, and the other - with a wide optical gap (Eg =3,45-3,55 eV) that corresponds to the diamond-like amorphous matrix of nanocomposite. According to the results of scanning tunneling microscopy (STM) and tunnel spectroscopy (TS), the size of graphite nanocrystals is about 1-2 nm and an amorphous shell around the graphite nanocrystals had a thickness of about 1.5 nm. The graphite component had n-type conductivity and an amorphous component had p-type conductivity. The electrical conductivity of such semiconductor nanocomposite was 103 S/m that to 6 orders higher compared to the DLC film in the amorphous state.
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