Anodic Niobium Pentoxide Films: Growth And Thickness Determination By In Situ Optoelectrochemical Measurements

Data on optical reflectance and anodization voltage, obtained during the galvanostatic anodization of metallic niobium foils in an H3PO4 (1%) solution at room temperature were simultaneously recorded as a function of time, to determine the thickness of the Nb2O5 films formed. From these data, plots of film thickness vs anodization voltage were obtained. A linear relation was always observed and in all cases but one, an angular coefficient of 22 Å V-1 was verified. © 1991.36812971300Stutzle, Huesler, Halbleitereigenschaften anodisch erzeugter Oxidschichten auf Niob (1969) Zeitschrift für Physikalische Chemie, 65, p. 201Gomes, Julião, Pinatti, (1988) Rev. Bras. Fis. Aplic. Instrum., 3, p. 300Goswami, Goswami, (1975) Indian J. pure appl. Phys., 13, p. 667Gomes, (1987) D.Sc. Thesis, , IFGW-UNICAMP, Campinas-SP-BrazilMcIntyre, Aspnes, (1971) Surf. Sci., 24, p. 417Ferreira, (1986) M.Sc. Thesis, , IFGW-UNICAMP, Campinas-SP-BrazilLee, Olive, Pulfrey, Young, Ionic Current as a Function of Field in the Oxide during Plasma Anodization of Tantalum and Niobium (1970) Journal of The Electrochemical Society, 117, p. 1172(1966) Handbook of Chemistry and Physics, , 47th edn, CRC-PressYoung, (1956) Trans. Faraday Soc., 52, p. 502Campbell, Peter, Determination of the density of lead dioxide films by in situ laser interferometry (1987) Electrochimica Acta, 32, p. 35