Contact Failure Due to Particulate Defect in a 0.13 µm CMOS Process

Random single bit failures were encountered in cache areas of Motorola’s 0.13 µm CMOS products under development. Extensive in-line probe data and end-of-line probe data in conjunction with failure analysis indicated the presence of particles at the upper surface of tungsten contacts. This paper describes how TEM based techniques were used to analyze the origin of the defect which in turn enabled process optimization and yield improvement.