Abstract
This paper presents data on the effect of electric pulses on thick film resistors made using Du Pont 1421 Birox resistor pastes.Resistance changes during the application of the electric pulses were investigated. Two types of change were observed: reversible and irreversible (i.e. catastrophic).In order to illustrate the causes of these changes, observations of the film on a scanning electron microscope were made. Microcracks were observed in the film, which were mostly responsible for the permanent resistance changes.