We present a new instrumentation for automated argon ion beam delayering of semiconductor devices that achieves nanometer-scale surface uniformity over millimeter-scale areas [Model 1064 ChipMill, Fischione Instruments]. Conventional delayering methods, including FIB and mechanical polishing, are limited by small processing areas, insufficient uniformity for thin layers (<200 nm), and potential sample damage. The presented system enables uniform delayering across areas up to 10 mm in diameter, providing high-quality surfaces for imaging and electrical characterization.
The instrument integrates a high-vacuum argon ion source (up to 10 keV) with a scanning electron microscope (SEM), backscattered electron detector (BSE), secondary electron detector, energy-dispersive X-ray spectroscopy (EDS), and an optical camera for in situ monitoring. A closed-loop feedback algorithm collects BSE images and EDS maps across the delayered area, calculates surface uniformity, and then dynamically adjusts the ion milling parameters to maintain nanometer-level planarity – independent of layer composition or device geometry.
Demonstration on an Apple A12 processor achieved surface uniformity within ±20 nm over a 5 mm diameter area and exposed multiple metal and dielectric layers in a single delayered plane. Critical subcomponents – including central processing unit, neural processing unit, caches, and interconnects – were clearly resolved, enabling detailed layer-specific analysis and vertical interconnect characterization.
This instrumentation provides a reproducible, scalable platform for large-area delayering and supports layer-resolved electrical probing, failure analysis, and reverse engineering of complex, multi-level semiconductor hardware. It enables uniform material removal and nanoscale surface flatness for advanced device analysis.