0599249 - FZÚ 2025 RIV US eng J - Journal Article
Niiranen, P. - Kapran, Anna - Nadhom, H. - Čada, Martin - Hubička, Zdeněk - Pedersen, H. - Lundin, D.
Plasma electron characterization in electron chemical vapor deposition.
Journal of Vacuum Science & Technology A : Vacuum, Surfaces and Films. Roč. 42, č. 2 (2024), č. článku 023006. ISSN 0734-2101. E-ISSN 1520-8559
Institutional support: RVO:68378271
Keywords : CVD * plasma electrons * plasma diagnostics
OECD category: Fluids and plasma physics (including surface physics)
Impact factor: 2.4, year: 2023 ; AIS: 0.525, rok: 2023
Method of publishing: Open access
DOI: https://doi.org/10.1116/6.0003408

Recently, a novel approach of depositing metallic films with chemical vapor deposition (CVD), using plasma electrons as reducing agents, has been presented and is herein referred to as e-CVD. By applying a positive substrate bias to the substrate holder, plasma electrons are drawn to the surface of the substrate, where the film growth occurs. In this work, we have characterized the electron flux at the substrate position in terms of energy and number density as well as the plasma potential and floating potential when maintaining an unbiased and a positively biased substrate. The measurements were performed using a modified radio frequency Sobolewski probe to overcome issues due to the coating of conventional electrostatic probes. The plasma was generated using a DC hollow cathode plasma discharge at various discharge powers and operated with and without precursor gas. With a precursor, an increase in the substrate bias shows a trend of increasing electron density. The electron temperature does not change much without precursor gas and is found in the range of 0.3–1.1 eV. Introducing a precursor gas to the vacuum chamber shows an increase in the electron temperature to a range of 1–5 eV and with a trend of decreasing electron temperature as a function of discharge power. From the values of the plasma potential and the substrate bias potential, we were able to calculate the potential difference between the plasma and the substrate, giving us insight into what charge carriers are expected at the substrate under different process conditions.
Permanent Link: https://hdl.handle.net/11104/0356800