Chemical resistance of thin film materials based on metal oxides grown by atomic layer deposition

• Published in: Thin solid films Vol. 542; pp. 219 - 224
• Main Authors: Sammelselg, Väino, Netšipailo, Ivan, Aidla, Aleks, Tarre, Aivar, Aarik, Lauri, Asari, Jelena, Ritslaid, Peeter, Aarik, Jaan
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 02-09-2013; Elsevier
• Subjects: Atomic layer deposition; Corrosion resistance; Cross-disciplinary physics: materials science; rheology; Crystal structure; Deposition; Etching; Exact sciences and technology; Materials science; Metal oxide coatings; Metal oxides; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Precursors; Silicon substrates; Theory and models of film growth; Thin films; Vapor phase epitaxy; growth from vapor phase; Wet chemical etching; X-ray fluorescence spectroscopy; X-ray fluorescence spectroscopy; Atomic layer deposition; Wet chemical etching; Metal oxide coatings; Atomic layer method; X ray fluorescence; Crystallization; Etching rate; Crystal growth from vapors; Chemical etching; Coatings; Precursor; Thin films; Metallic thin films; Residual impurity; Growth mechanism; Chromium; Titanium
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2013.06.079

Etching rate of technologically important metal oxide thin films in hot sulphuric acid was investigated. The films of Al-, Ti-, Cr-, and Ta-oxides studied were grown by atomic layer deposition (ALD) method on silicon substrates from different precursors in large ranges of growth temperatures (80–900°C) in order to reveal process parameters that allow deposition of coatings with higher chemical resistance. The results obtained demonstrate that application of processes that yield films with lower concentration of residual impurities as well as crystallization of films in thermal ALD processes leads to significant decrease of etching rate. Crystalline films of materials studied showed etching rates down to values of <5pm/s.
•Etching of atomic layer deposited thin metal oxide films in hot H2SO4 was studied.•Smallest etching rates of <5pm/s for TiO2, Al2O3, and Cr2O3 were reached.•Highest etching rate of 2.8nm/s for Al2O3 was occurred.•Remarkable differences in etching of non- and crystalline films were observed.