Electron spin resonance study of hydrogen-free germanium-doped diamond-like carbon films

0562089 - FZÚ 2024 RIV DE eng J - Journal Article
Holiatkina, M. - Savchenko, Dariia - Kocourek, Tomáš - Prokhorov, Andriy - Lančok, Ján - Kalabukhova, E.
Electron spin resonance study of hydrogen-free germanium-doped diamond-like carbon films.
Physica Status Solidi B. Roč. 260, č. 1 (2023), č. článku 2200155. ISSN 0370-1972. E-ISSN 1521-3951
R&D Projects: GA MŠMT(CZ) EF16_019/0000760
Grant - others:OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institutional support: RVO:68378271
Keywords : diamond-like carbon film * selectron spin resonance * germanium doping
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 1.6, year: 2022
Method of publishing: Limited access
https://doi.org/10.1002/pssb.202200155

Hydrogen-free germanium (Ge)-doped diamond-like carbon (DLC) films deposited on SiO2 substrates are studied by electron spin resonance (ESR) technique at T ¼ 5–295 K. The Ge-free and DLC films with 1 and 2.5 at% Ge content having low cytotoxicity are investigated. A single Lorentzian ESR line resulting from exchange interaction between localized (LE) and nonlocalized electrons (NE) is observed. The spin susceptibility temperature dependence deviates from the Curie–Weiss law at T >75 K due to Pauli contribution caused by NE. The antiferromagnetic lowtemperature spin ordering in DLC films, decreasing with Ge content, is observed. The LE contribution is significant for Ge-free and DLC:1%Ge, whereas NE makes the main contribution to DLC:2.5%Ge. The LEs are related to sp2/sp carbon-related centers, while the NEs are assigned with electrons in the sp3 orbital. The correlation between the sp3/sp2 ratio and the shift of g-factor for NE to lower values with Ge doping is established.

Permanent Link: https://hdl.handle.net/11104/0338279