Determination of Current Capacity of Small Dimension Wires and Bars

Recent experience with damaged components because of electrical overstress prompted reevaluation of the current capacity of small dimension wires and metallic film interconnects. It was part of the investigation to relate the damage ovserved to a quantitative description to the stress in terms of energy and duraction. Evaluation of component capabilities in relation to component design and environment then determine if that component is suitable for the particular application. From this information, recommendations on component design or application may be advanced to preclude recurrence. Quantitative description of damage identify if the faulting mechanism is inherent in the component or its intended environment, or whether the damage was a random occurrence. From a description of the physical aspects of the damage and knowledge of the thermodynamic environment, the energy responsible for the damage is otained. The energy sources are then identified and the potential recurrence of such damage evaluated. A physical model to support the experimental work, applicable to extended physical situations, has been developed and verified. Rates of mass evaporation with respect to energy are established. Transfer rates of energy to the supporting substrate are established.