Ceramic films density

The double-layer capacitor is one of the electrochemical capacitors showing intermediate performances between conventional capacitors and rechargeable batteries from the viewpoint of energy and power densities. Although the terms supercapacitor and ultracapacitor are often used for double-layer capacitors, in a sense that they have higher capacitance than conventional capacitors (ceramic, film, aluminum electrolytic, or tantalum electrolytic capacitors), these terms are not to be used because they are the trademarks of certain companies products. 

The surface layers are mainly characterised by the formation of mono- and diboride arrays[2,5]. As found [8], the boron depleated composites have the tendency to form ceramic films of high density and avoid crack formation by prevailing compressive residual stress. Therefore the surface films show excellent adhesion enhancing the resistance against abrasion[8,12]. 

Fig. 4.15. Binding energy difference between Zn2p3/2 and O Is core levels and between the core levels and the valence band maximum. Films are deposited by dc magnetron sputtering from undoped and 2 % Al-doped ceramic targets at room temperature in dependence of sputter gas composition (left) and in pure Ar in dependence on substrate temperature (right). All films were deposited using a total pressure of 0.5 Pa, a sputter power density of 0.74 W cm-2 and a substrate to target distance of 10 cm...

Properties such as high density and homogenous conductivity define the quality of ceramic targets. Ceramics with nonconductive inclusions exhibit arcing and nodule growth on the target surface, while targets with low density exhibit inferior film properties due to contaminations with different species. 

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