Abstract Focused ion beam (FIB) techniques are often used when delayering semiconductor devices. However, using FIB technology for device delayering has limitations. One of these limitations prevents the exposure of a large slope area on the sample, which reveals all layers simultaneously. The delayering process is complex and requires prior process knowledge, such as cross-section architecture, composition, and layer uniformity. This paper discusses advances in semiconductor device deprocessing for product development, failure analysis, and quality control using low-energy, argon broad ion beam (BIB) milling. Ar BIB milling is a practical solution for accurate delayering of advanced microelectronic devices. Results of the spot milling of a whole 300 mm wafer experiment and top-down delayering of wafer pieces experiment show that successful device delayering can be achieved by either spot milling or layer-by-layer milling. These two strategies are easily achieved, for either small wafer pieces or full 300 mm wafer investigation.