Epitaxial nickel disilicide with low resistivity and excellent reliability

Ultra-thin epitaxial NiSi₂ was formed, and its structure was examined by electron microscopy and x-ray diffraction. Compared with previous reports, the measured resistivity of the epitaxial NiSi₂ was unprecedentedly low, reaching 7 μΩ cm in the experimental results and up to 14.93 μΩ cm after modification. The reliability, which was investigated under different temperatures and current densities to understand its electronic characteristics, was 1.5 times better than that of the conventional polycrystalline counterpart. Black's equation and the measured mean-time-to-failure (MTTF) were used to obtain the reliability characteristics of epitaxial and poly-NiSi₂. Confidence intervals at 95% for each MTTF confirmed the single failure mode. The electromigration phenomenon was observed to be the failure mechanism. Our results provide evidence that epitaxial NiSi₂ is a promising contact material for future electronics.