Simulation of density variation and step coverage for via metallization

A ballistic deposition technique, SIMBAD, has been developed and used to simulate sputter deposition of metal over a 2- mu m step and over 1- mu m vias of various geometries. In addition to generating step coverage and surface profiles at different stages of growth, SIMBAD provides further information unattainable through conventional film growth simulation packages. Predictions of local film density and microstructure are presented, and low-density regions occurring on the sidewalls and in corners of steps and vias are analyzed.<
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