Next Article in Journal
The Effect of Varying Abutment Heights on Stress Distribution in Different Bone Densities: A Finite Element Analysis Study
Previous Article in Journal
The Reflection Coefficient |r| as a Nondestructive Measure of the Coating Adhesion to a Steel Substrate
 
 
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
This is an early access version, the complete PDF, HTML, and XML versions will be available soon.
Article

Topographic, Thermal and Chemical Characterization of Oxidized Cu and Cu-Ag Thin Films

1
CEMMPRE, Department of Mechanical Engineering, University of Coimbra, 3030-788 Coimbra, Portugal
2
iBB, Interdisciplinary Complex, Instituto Superior Técnico, University of Lisbon, 1049-001 Lisbon, Portugal
3
CQE—Instituto Superior Técnico, Department of Chemical Engineering, University of Lisbon, 1349-017 Lisbon, Portugal
*
Author to whom correspondence should be addressed.
Materials 2025, 18(19), 4562; https://doi.org/10.3390/ma18194562
Submission received: 23 August 2025 / Revised: 20 September 2025 / Accepted: 29 September 2025 / Published: 30 September 2025
(This article belongs to the Section Thin Films and Interfaces)

Abstract

This study investigated the effects of silver doping, natural ageing, and thermal-induced oxidation on the surface chemistry, morphology, and thermal performance of copper thin films. Ag is used as a doping element in Cu because, in bulk materials it usually refines microstructures, leading to increased hardness and mechanical strength through mechanisms such as solid solution strengthening and twinning. In this work was also used due to its oxidation resistance. Thin films of pure and silver-doped copper (Cu_2Ag and Cu_4Ag) were deposited by RF magnetron sputtering and characterized as-deposited, naturally aged, at room temperature and humidity for one year, and thermally treated at 200 °C, in air. The characterization included X-ray photoelectron spectroscopy (XPS), Atomic Force microscopy (AFM), and thermal analysis, specifically thermal conductivity (λ), thermal diffusivity (α), and thermal capacity (ρ.Cp). Surface XPS analysis revealed changes in copper and silver oxidation states after natural aging and annealing. AFM revelead that the incorporation of silver and heat treatment altered the surface roughness and morphology. Thermal analysis found that for lower silver concentrations, the thermal conductivity increased, but aging and annealing had varying effects depending on the silver content. The Cu_4Ag film showed the best thermal stability after natural ageing. Overall, the results suggest that carefully controlled silver doping can enhance the thermal stability of copper thin films for applications where aging is a concern, such as microelectronics.
Keywords: Cu-Ag thin films; natural and thermal oxidation; thermal conductivity; thermal diffusivity; thermal capacity Cu-Ag thin films; natural and thermal oxidation; thermal conductivity; thermal diffusivity; thermal capacity

Share and Cite

MDPI and ACS Style

Carrupt, M.C.; Ferraria, A.M.; Serro, A.P.; Piedade, A.P. Topographic, Thermal and Chemical Characterization of Oxidized Cu and Cu-Ag Thin Films. Materials 2025, 18, 4562. https://doi.org/10.3390/ma18194562

AMA Style

Carrupt MC, Ferraria AM, Serro AP, Piedade AP. Topographic, Thermal and Chemical Characterization of Oxidized Cu and Cu-Ag Thin Films. Materials. 2025; 18(19):4562. https://doi.org/10.3390/ma18194562

Chicago/Turabian Style

Carrupt, Maria C., Ana M. Ferraria, Ana P. Serro, and Ana P. Piedade. 2025. "Topographic, Thermal and Chemical Characterization of Oxidized Cu and Cu-Ag Thin Films" Materials 18, no. 19: 4562. https://doi.org/10.3390/ma18194562

APA Style

Carrupt, M. C., Ferraria, A. M., Serro, A. P., & Piedade, A. P. (2025). Topographic, Thermal and Chemical Characterization of Oxidized Cu and Cu-Ag Thin Films. Materials, 18(19), 4562. https://doi.org/10.3390/ma18194562

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop