Electrochemical and time-of-flight secondary ion mass spectrometry analysis of ultra-thin metal oxide (Al2O3 and Ta2O5) coatings deposited by atomic layer deposition on stainless steel

Abstract : Ultra-thin (5-50 nm) layers of aluminium and tantalum oxides deposited by atomic layer deposition (ALD) on a stainless steel substrate (316L) for corrosion protection have been investigated by electrochemical methods (linear scan voltammetry, LSV, and electrochemical impedance spectroscopy. EIS) and time-of-flight secondary ion mass spectrometry, ToF-SIMS. The effects of the deposition temperature (250 degrees C and 160 degrees C) and coating thickness were addressed. ToF-SIMS elemental depth profiling shows a marked effect of the organic and water precursors used for deposition and of the substrate surface contamination on the level of C and OH trace contamination in the coating, and a beneficial effect of increasing the deposition temperature. The polarization data show a decrease of the current density by up to four orders of magnitude with increasing coating thickness from 5 to 50 nm. The 50 nm films block the pitting corrosion in 0.8 M NaCl. The uncoated surface fraction (quantified from the current density and allowing a ranking of the efficiency of the coating, also confirmed by the capacitance and resistance values extracted from the EIS data) was 0.03% with a 50 nm thick Al2O3 film deposited at 250 degrees C. The correlation between the porosity values of the coatings and the level of C and OH traces observed by ToF-SIMS points to a marked effect of the coating contaminants on the sealing performance of the coatings and on the corrosion resistance of the coated systems. (C) 2011 Elsevier Ltd. All rights reserved.
Type de document :
Article dans une revue
Electrochimica Acta, Elsevier, 2011, 56 (28, SI), pp.10516-10523. 〈10.1016/j.electacta.2011.02.074〉
Liste complète des métadonnées

https://hal.archives-ouvertes.fr/hal-01822581
Contributeur : Laboratoire Mateis <>
Soumis le : lundi 25 juin 2018 - 12:26:25
Dernière modification le : mercredi 12 décembre 2018 - 15:30:58

Identifiants

Citation

Belen Diaz, Jolanta Swiatowska, Vincent Maurice, Antoine Seyeux, Bernard Normand, et al.. Electrochemical and time-of-flight secondary ion mass spectrometry analysis of ultra-thin metal oxide (Al2O3 and Ta2O5) coatings deposited by atomic layer deposition on stainless steel. Electrochimica Acta, Elsevier, 2011, 56 (28, SI), pp.10516-10523. 〈10.1016/j.electacta.2011.02.074〉. 〈hal-01822581〉

Partager

Métriques

Consultations de la notice

44