X-ray diffraction determination of the effect of various passivations on stress in metal films and patterned lines

Abstract

Direct x-ray diffraction determination of elastic strain and stress in aluminum and aluminum-silicon films and patterned lines has been used to investigate the effect of various passivations. Passivation over uniform metal films has very little effect. Passivation over patterned metal results in substantial triaxial tensile stress. Contrary to the conventional wisdom, high compressive stress in the passivation does not result in additional tensile stress in the metal. The deleterious effects of highly compressive silicon nitride on metal is probably due to the effect of excess hydrogen in the silicon nitride.