Current Load of Thick-film Pastes for Power Applications

This paper deals with the current-carrying capacity of silver cermet thick-film conductors. Ten different patterns of thick-film conductors were created on the alumina substrate (96 % Al$_{2}O_{3}$). The electrical current load concerning the width of the conductive path was determined from the performed measurements. During the measuring process, the electrical current was rising by 0.1A per 10s increasing voltage and temperature. Conductive path widths from 0.20 - 0.65 in 0.05mm steps were tested. The terminals on the samples were connected by two methods, mechanical and solder joints. Results showed that the thick-film path was working up to 550°C, with the current load up to approximately 8.6A for mechanically connected terminals. Soldered terminals were loaded by up to 7.1A and its temperature increased to 350° C. Both results were measured for 0.65mm path width.