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Superconductivity, Spintronics and Surface Science Center

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test.jpgThin Films
   
Oxide thin films have a large range of applications in electronics, optics, catalysis, wear resistance, corrosion protection and superconductivity. The sol-gel processing route is particularly attractive for fabricating oxide thin films, since the liquid precursor can easily be applied on a substrate by dipping, spinning or spraying. The two principal gel-processing routes for oxide ceramics involve the gelation of either a sol by the removal of water, or the crosslinking of inorganic polymers by the hydrolysis of metal alkoxides in an alcoholic solvent. For both routes, the final conversion to oxides is accomplished by heat-treating the dried gel, resulting in either polycrystalline or oriented (epitaxial) thin films.
 
   
CSD
 
Fig. 1 Overview of the chemical solution deposition process.
 

> Thin films by chemical solution deposition (CSD)

 
  • YBa2Cu3O7-x
 
YBCO by CSD
   
  • La0.66Sr0.33MnO3 (LSMO)
 
LSMO-STO-1000 02.jpg(a)
LSMO-STO-1100 03.jpg(b)

*The precursor solution for the deposition epitaxial   thin films has been prepared at room temperature starting from metal acetates, acetylacetonates and propionic acid.

 

M. Nasui, T. Petrisor Jr., R.B. Mos , M.S. Gabor , T. Ristoiu , A. Rufoloni, L. Ciontea, T. Petrisor, Thin Solid Films 518 (2010) 4753–4756.

> La0.66Sr0.33MnO3 thin films annealed at 800 oC (a) and 1100 oC (b) in air.
   
  • La2Zr2O7(LZO)
 
*The precursor solution for the deposition of epitaxial LZO thin films has been prepared at room temperature starting from lanthanum (III) 2,4-pentadionate and zirconium (IV) 2,4- pentadionate with a purity of 99.9% purchased from Alfa Aesar. They were separately dissolved in an excess of propionic acid (CH3CH2COOH) and mixed in stoichiometric quantities corresponding to La:Zr = 1:1 ratio to form lanthanum and zirconium propionates. The as-obtained solution was concentrated by distillation under severe conditions up to a 0.4 mol/l concentration.
  • BaZrO3(BZO)
 

*The coating solution was prepared starting from barium acetate Ba(CH3COO)2· xH2O and zirconium acetylacetonate [Zr(CH3COCHCOCH3)4]· xH2O. While the zirconium acetylacetonate was simply dissolved in an excess of propionic acid C2H5COOH, the barium acetate was separately dispersed in methanol, an excess of propionic acid was added and further treated with ammonia until the solution became clear. The two solutions were mixed together under stirring and concentrated by distillation under vacuum (42 mbarr, bath temperature 75oC) for the removal of solvents.

 

    R.B. Mos, M.S. Gabor , M. Nasui , T. Petrisor Jr , C. Badea, A Rufoloni, L. Ciontea, T. Petrisor, Thin Solid Films 518 (2010) 4714–4717.