Co-precipitation synthesis in the presence of surfactant and characterization of nanosized CaRuO3 powders and its application in fired thick film resistors in nanoelectronics

In this paper, we are presenting the co-precipitation synthesis of CaRuO3 from the solutions of CaCl2·2H2O and RuCl3·xH2O in the presence of CTAB as the surfactant at pH 9.41 and dried at 100 °C in air and at 250 °C in vacuum. The resultant powders were characterized by TGA/DTA, SEM-EDX, XRD, and TEM-SAED techniques. The transmission electron micro-structural studies of powders revealed that the average particle size is around 12 nm. The particle size of CaRuO3 powder prepared by this solution route without CTAB is around 150–250 nm and solid-state route is 300–400 nm. The resistor paste was formulated by using nano-powders of CaRuO3 and lead borosilicate glass admixtures pre-heated at 600 °C and peak firing at 850 °C. The electrical studies (sheet resistance and hot/cold temperature coefficient of resistance) of fired thick film resistors prepared from these powders are presented in this paper. We are also presenting the investigation of cross sectional microstructures of above fired thick film resistors. The hot and cold TCR values are higher than the expected values due to the processing of the paste in less than 1 g and non-exchange reactions between Ca2+ and Pb2+ of functional material and glass respectively due to ionic radii difference of these two metal ions.