Search results for "Anodic oxides"
showing 10 items of 12 documents
Characterization of the Solid State Properties of Anodic Oxides on Magnetron Sputtered Ta, Nb and Ta-Nb Alloys
2012
Tantalum oxide, niobium oxide and Ta-Nb containing mixed oxides were grown by anodizing sputter-deposited Ta, Nb and Ta-Nb alloys of different compositions. A photoelectrochemical investigation was performed in order to estimate the band gap and the flat band potential of the oxides as a function of their composition. The band gap of the investigated Ta-Nb containing mixed oxides changed monotonically between those estimated for Ta2O5 (4.1 eV) and Nb2O5 (3.4 eV) and in agreement with a proposed correlation between the Band gap of an oxide and the difference of electronegativity of the oxide constituents. From the differential capacitance curves recorded in a wide range of electrode potentia…
Characterization of Anodic Oxides on Titanium by Photocurrent and Differential Admittance Techniques
2010
Characterization of Anodic Oxides on Magnetron Sputtered Ta-Nb Alloys by Photocurrent Spectroscopy and Differential Admittance Measurements
2010
ELECTROCHEMICAL FABRICATION OF METAL/OXIDE/CONDUCTING POLYMER JUNCTIONS FOR ELECTRONIC DEVICES
2014
Electrochemically Prepared High-k Thin Films for Resistive Switching Devices
Anodization and anodic oxides
2018
Anodizing is a low-temperature, low-cost electrochemical process allowing for the growth, on the surface of valve metals and valve metal alloys, of anodic oxides of tunable composition and properties. This article is an overview on theoretical aspects concerning the general aspects of the kinetics of growth of barrier and porous anodic oxides and some of their present and possibly future technological applications of anodic oxides. The first part of the article is devoted to anodic oxide growth models, from Guntherschulze and Betz work (in 1934) to the more recent results on barrier and porous oxide films. The second part is focused on industrial processes to fabricate anodic oxides and the…
Characterization of the Solid State Properties of Anodic Oxides on Ta-Nb Alloys as a Function of the Anodizing Conditions
2011
Tantalum oxide, niobium oxide and Ta-Nb containing mixed oxides were grown by anodizing sputter-deposited TaxNb(1-x) alloys with 0 ≤ x ≤ 1. A photoelectrochemical investigation was performed in order to estimate the band gap values of the oxides as a function of their composition as well as to estimate their flat band potential. Differential capacitance curves were recorded for all the investigated oxides in a wide range of electrode potential and for several frequencies of the alternative signal. The dependence of C on the applied potential and a.c. frequency was interpreted on the basis of amorphous semiconductor Schottky barrier, and allowed to estimate the dielectric constant of the inv…
The Effect of Nb Incorporation on the Electronic Properties of Anodic HfO2
2017
Hafnium oxide and Nb doped HfO2 were grown by anodizing sputtering-deposited Hf and Hf-4at.%Nb. Photoelectrochemical characterization was carried out in order to estimate solid state properties such as band gap, flat band potential and electrons internal photoemission threshold energy as a function of thickness and composition of anodic oxides. Optical transitions at energy lower than the band gap value of the investigated anodic films were evidenced, and they are attributed to optical transitions involving localized states inside the band gap. Such states were located at 3.6 eV and 3.9 eV below the conduction band edge for the Nb free and Nb containing hafnium oxide, respectively. Impedanc…