화학공학소재연구정보센터
Journal of Materials Science, Vol.50, No.23, 7600-7609, 2015
XPS depth profiling and leakage properties of anodized titania dielectrics and their application in high-density capacitors
The chemical structure and electrical properties of anodized titania are investigated for their application as conformal ultra-thin dielectrics on high surface area titanium electrodes. The chemical structure is studied by XPS depth profiling for the first time along with the role of anodization conditions on dielectric thickness, leakage current, and capacitance densities. Different leakage current models were used to identify the defect mechanisms in the titania film formed at different voltages. EDS and structural SEM studies were performed to investigate the morphology and structure of the titania films. This research also demonstrates the fabrication and characterization of high-density capacitors using high surface area titanium metal electrodes, conformal high K, and thin-film dielectric of titania. High-permittivity and thin-film titania dielectric was grown on high surface area titanium anodes using anodization, while conducting polymer was used as the cathode. The fabricated capacitor showed 7.15 A mu F cm(-2) at 100 kHz which corresponded to 7.5X enhancement in surface area compared to planar thin-film capacitors. This is the first demonstration of high-density capacitors using high surface area titanium anodes along with high-permittivity and thin-film titania as the dielectric.