Stress in metal lines under passivation; comparison of experiment with finite element calculations

The elastic strain in Al-0.5% Cu metal lines under silicon nitride passivation has been determined by x-ray diffraction. The experimental stress tensor calculated from these strain values is in excellent agreement with the results of a finite element model calculation. The intrinsic stress in the dielectric plays no role in influencing the stress in the metal; only thermal stress effects are important.