title: Structural study of very thin anodic alumina films on silicon by anodization in citric acid aqueous solution.
abstract: The formation of thin alumina films on a silicon substrate by anodization in a mild acid, specifically in 1% wt citric acid aqueous solution, is investigated by transmission electron microscopy (TEM). We present a comparative study between two cases of starting material: pure aluminum and an alloy of aluminum with 1% silicon. In both cases the thickness of the Al layer was less than 50 nm. It was observed that under exactly the same conditions, in the first case the anodization was stopping before anodizing the whole film and a remaining non-anodized Al layer was always present, while in the second case, the Al layer was fully anodized, resulting in an alumina matrix with a very high density of silicon nanocrystals of uniform sizes embedded in it. In both cases the alumina film was compact and amorphous.
authors.affiliation: IMEL/NCSR Demokritos, PO BOX 60228, 153 10 Aghia Paraskevi, Athens, Greece.
authors.forename: M
authors.initials: M
authors.lastname: Kokonou
authors.forename: A G
authors.initials: AG
authors.lastname: Nassiopoulou
authors.forename: K P
authors.initials: KP
authors.lastname: Giannakopoulos
authors.forename: N
authors.initials: N
authors.lastname: Boukos
authors.forename: A
authors.initials: A
authors.lastname: Travlos
mesh_terms: D000537:Aluminum Oxide / Q000032:analysis / Q000737:chemistry*; D019343:Citric Acid / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D004566:Electrodes; D004595:Electroplating / Q000379:methods*; D008422:Materials Testing; D008567:Membranes, Artificial; D049329:Nanostructures / Q000032:analysis / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D016062:Porosity; D012996:Solutions; D013499:Surface Properties
chemical_list: D020099:Coated Materials, Biocompatible; D008567:Membranes, Artificial; D012996:Solutions; D019343:Citric Acid; D000537:Aluminum Oxide