Lithuanian Journal of Physics article / Lietuvos fizikos žurnalo straipsnis

[PDF] http://dx.doi.org/10.3952/lithjphys.45405

Open access article / Atviros prieigos straipsnis

Lith. J. Phys. 45, 289–295 (2005)

SELF-FORMATION OF Fe/Fe-O NANOPARTICLES IN POROUS SiO₂ FILMS^∗
I. Šimkienė^a,b, J. Sabataitytė^a,c, M. Baran^d, R. Szymczak^d, J.-G. Babonas^a,c, A. Rėza^a,e, and A. Kaliničenko^f
^aSemiconductor Physics Institute, A. Goštauto 11, LT-01108 Vilnius, Lithuania
^bVilnius University, Saulėtekio 9, LT-10222 Vilnius, Lithuania
^cVilnius Gediminas Technical University, Saulėtekio 11, LT-10223 Vilnius, Lithuania
^dInstitute of Physics, PAN, Al. Lotnikow 32/46, 02-668 Warsaw, Poland
^eVilnius Pedagogical University, Studentų 39, LT-08106 Vilnius, Lithuania
^fInstitute of Chemistry, A. Goštauto 10, LT-01108 Vilnius, Lithuania

Received 13 June 2005

Self-formation of Fe/Fe-O particles in porous SiO₂ films has been studied by investigating the structure and physical properties of hybrid samples SiO₂:Fe/SiO₂/Si. The sol–gel spin-on technique was used for the formation of Fe-doped silica films on silica-coated Si wafers. The sol was prepared from precursors composed of ethanol and/or aqueous solutions of tetraethoxysilane (TEOS) and FeCl₃. As-grown hybrid samples were annealed in Ar atmosphere. Structural studies by means of atomic force microscopy (AFM) have shown a different morphology of samples produced from precursors with various Fe-amount. Spectroscopic ellipsometry measurements were carried out for characterization of the contribution of Fe/Fe-O clusters to the optical response of hybrid samples. Magnetic properties of Fe-doped silica films were studied by measuring the magnetic field and temperature dependences of magnetization. Experimental data were interpreted taking into account particular features of Fe and Fe-O nanoparticles in silica matrix.

Keywords: nanoscale materials and structures, fabrication and characterization
PACS: 81.07.-b, 81.16.Dn
^∗The report presented at the 36th Lithuanian National Physics Conference, 16–18 June 2005, Vilnius, Lithuania

Fe/Fe-O NANODALELIŲ SAVAIMINIS SUSIDARYMAS PORĖTOSIOSE SiO₂ PLĖVELĖSE
I. Šimkienė^a,b, J. Sabataitytė^a,c, M. Baran^d, R. Szymczak^d, J.-G. Babonas^a,c, A. Rėza^a,e, A. Kaliničenko^f
^aPuslaidininkių fizikos institutas, Vilnius, Lietuva
^bVilniaus universitetas, Vilnius, Lietuva
^cVilniaus Gedimino technikos universitetas, Vilnius, Lietuva
^dLenkijos MA Fizikos institutas, Varšuva, Lenkija
^eVilniaus pedagoginis universitetas, Vilnius, Lietuva
^fChemijos institutas, Vilnius, Lietuva

Išnagrinėtas Fe/Fe-O dalelių savaiminis susidarymas porėtosiose SiO₂ plėvelėse, tiriant hibridinių SiO₂:Fe/SiO₂/Si darinių sandarą ir fizikines savybes. Fe priemaišintos Si oksido plėvelės buvo suformuotos centrifūgoje ant SiO2₂ sluoksniu padengtų Si plokštelių, panaudojant zolio–gelio metodiką. Zolis buvo paruoštas iš etanolo ir / arba vandeninių tetraetoksisilano ir FeCl₃ tirpalų. Suformuoti hibridiniai dariniai buvo atkaitinti Ar atmosferoje. Sandaros tyrimai atominės jėgos mikroskopu parodė, kad bandinių su įvairiu Fe kiekiu morfologija yra skirtinga. Spektroskopinė elipsometrija atlikta, siekiant apibūdinti Fe/Fe-O klasterių indėlį į hibridinių darinių optinį atsaką. Fe priemaišintų SiO₂ plėvelių magnetinės savybės buvo tiriamos, matuojant magnetinio momento priklausomybes nuo magnetinio lauko ir temperatūros. Eksperimentiniai rezultatai aiškinami, atsižvelgiant į Fe ir Fe oksidų nanodalelių ypatumus silicio oksido matricoje.

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