Thermoanalytische und massenspektrometrische Untersuchungen an Widerstandsschichten für AIN-Substrate

AIN represents a real alternative to other substrate materials such as alumina because of its excellent physical and chemical properties. The field of application will depend on the realization of thick film conductors, resistors and dielectrics. Commercially available resistor pastes for alumina blister on AIN during firing process and form so non-functionally layers. One of the reasons of bubbles in resistor layers on AIN can be reactions between components of layer and substrate. For example ruthenium dioxide, which is used in resistor pastes, can be reduced by AIN, whereby alumina, pure ruthenium metal and gaseous nitrogen created. To characterize this reaction, thermoanalytical (DTA and TG) and mass-spectrometric (QMS) measurements carried out in air and in inert gases. The interpretation of results is assisted by XRD- measurements.