A fractal approach to electrolytic capacitors for implantable devices

Electrolytic capacitors for implantable devices need an improvement in respect to size and contact reliability. In the following a new design of dry tantalum capacitors will be presented using thin films with a fractal surface structure. The achieved capacities related to the projected substrate area are presently in the same range as for commercially available SMT-components, but the height of the devices is reduced to 1/5. Furthermore the reliability in respect to the contact is highly improved by using standard thick film technology.