Rapid cross-sectioning of challenging samples using a combination of TRUE X-sectioning and the rocking stage techniques

An advanced sample preparation protocol using Xe
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Plasma FIB for cross-sections wider than 400 μm is proposed. Challenging samples such as a BGA (CSP) or chip in a package often suffer from FIB milling artifacts. The results are unsatisfactory mainly due to different milling rates of the various materials (polyimide, tin, copper), ion beam induced ripples or due to significant topography. The process parameters of the proposed approach are compared with the standard methods with respect to cross-section quality as well as preparation time. The new approach is then combined with the Rocking stage which greatly improves cross-section quality.