Automated End-Point Detection and Targeted Ar⁺ Milling of Advanced Integrated Circuit FIB TEM Specimens

The sub-nanometer resolution that transmission electron microscopy (TEM) provides is critical to the development and fabrication of advanced integrated circuits. TEM specimens are usually prepared using the focused ion beam, which can cause gallium-induced artifacts and amorphization. This work presents the use of a concentrated argon ion beam for reproducible TEM specimen preparation using automatic milling termination and targeted ion milling of device features; the result is high-quality and electron-transparent specimens of less than 30 nm. Such work is relevant for semiconductor product development and failure analysis.