Characterisation of titanium passivation films by in situ ac impedance measurements and XPS analysis

• Type: Article in International Scientific Journal
• Date: 1994

Authors

C. Fonseca (Author) Other; Boudin, S (Author) Other; da Cunha Belo, M (Author) Other

Journal

The Journal is awaiting validation by the Administrative Services.

Title: JOURNAL OF ELECTROANALYTICAL CHEMISTRY

Vol. 379

Pages: 173-180

ISSN: 0022-0728

Indexing

Scopus - 54 Citations

Other information

Authenticus ID: P-00P-WGT

DOI: 10.1016/0022-0728(94)87136-1

Abstract (EN): Capacitance-potential measurements by ac impedance methods have shown that for polarisations of 0.5 to 0.7 V from the flat band potential, titanium passivation films formed between 0.2 and 2 V (thicknesses ranging from 15 to 100 Å) display Mott-Schottky behaviour, with frequency dependent slopes. This study develops a theoretical approach which takes account of the frequency dispersion and allows the determination of flat band potentials, donor densities, and Helmholtz capacitances for the films. The Mott-Schottky behaviour was attributed to the presence of Ti3+ as the doping element. Experimental evidence for this was obtained from XPS spectra. For films formed above 2 V the linear Mott-Schottky region was difficult to define, and capacitance vs. potential plots resembled the behaviour of amorphous semiconductors. © 1994.

Language: English

Type (Professor's evaluation): Scientific