Journal
COLLOIDS AND SURFACES B-BIOINTERFACES
Volume 56, Issue 1-2, Pages 163-169Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.colsurfb.2006.10.021
Keywords
dielectric permittivity; electrostriction; anodising; integrated biosensors
Ask authors/readers for more resources
Further improving the performance of capacitance-based DNA microsensors will depend on the ability to synthesize simply, at a low cost, thin films of high dielectric permittivity with a well-controlled growth morphology. Anodisation of the valve metals Ti, Zr and Ta is a promising route for preparing such films. In this paper, we propose a new method for following the evolution of the dielectric properties of such anodised metallic oxide thin films in-situ during their growth. The technique relies on measuring the evolution of the electrostatic stress developing in the film. Measurements have been carried out on anodic TiO2 films grown galvanostatically in HNO3 at 1 and 3 mA/cm(2) and in H3PO4 at 0.5 mA/cm(2). The dielectric permittivity of the filrus was observed to decrease during the initial stage of anodisation, characterised by a steady increase of the cell voltage with time. The permittivity then reached a constant value when the oxide entered a second growth regime, characterised by a stabilisation of the cell voltage. The origin of the observed permittivity evolution is interpreted in terms of the evolution of the growth morphology of the films during anodisation. (c) 2006 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available