The Microstructure of RuO2Thick Film Resistors and the Influence of Glass Particle Size on their Electrical Properties

The microstructure and electrical properties of RuO2thick film resistors have been studied with special emphasis on the effects of material parameters and processing variables such as size of glass frit particles, RuO2-glass mixing ratio, firing conditions, and so forth. A network of RuO2develops in a glass matrix on firing, and the increase in the glass particle size enlarged the cell in the network without any significant change in the microstructure. It is shown that a decrease in particle size of glass frit increases the resistance and causes the temperature coefficient of resistor (TCR) to take negative values.