Qualification of inline FIB for production — A comprehensive “BEOL” contamination study

In-line FIB (Focused Ion Beam) systems have become an important tool for failure analysis in the chip manufacturing production line. A general problem that in-line FIB users face is how to qualify returning wafers to production after FIB milling. In this paper we will present a set of experiments defined for qualifying in-line FIB production work in a 90nm generation FLASH production fab. The effect of FIB cuts on further process steps, cross tool contamination, the impact on yield and parametric testing were studied and will be discussed.