Thermal Stress Induced Void Formation in Narrow Passivated Cu Lines

Abstract

ABSTRACT0.75–3 μm wide copper lines encased in a thin adhesion layer of Al or Cr were passivated at 300°C and annealed at 400°C. The passivation was then removed and the lines examined in a scanning electron microscope. The development of thermal stress induced voiding was found to depend primarily on aging conditions and adhesion.