SIMULATION OF ELECTROMIGRATION BASED ON RESISTOR NETWORKS

A two-dimensional computer simulation of electromigration based on res istor networks is presented. The model utilizes a realistic grain stru cture generated by the Monte Carlo method and takes specific account o f the local effects through which electromigration damage progresses. The dynamic evolution of the simulated thin film is governed by the lo cal current and temperature distributions. The current distribution is calculated by superimposing a two-dimensional electrical network on t he lattice whose nodes correspond to the particles in the lattice and the branches to interparticle bonds. The current distribution problem is solved by applying Kirchoff's rules on the resulting electrical net work. The calculation of the temperature distribution in the lattice p roceeds by discretizing the partial differential equation for heat con duction, with appropriate material parameters chosen for the lattice a nd its defects. The simulation was tested by applying it to common sit uations arising in experiments with real films. Specifically, the mode l successfully reproduces the expected grain size, linewidth and bambo o effects, the log-normal failure time distribution, and the relations hip between current-density exponent and current density.