Abstract This paper presents a first approach to failure analysis using FIB ToF-SIMS for increasingly smaller feature sizes. In particular, the detectability of B and P in the borophosphosilicate glass layers present in IMD (Inter-Metal Dielectric) stacks is discussed. The innovation is that we try to do a cross-sectional SIMS analysis, trying to bring us as close as possible to the analytical performance of conventional standalone SIMS. The result is very promising, although there is still a lot of work to be done to find an analytical protocol that minimizes the effects induced by instrumental limitations, ensures repeatability, and allows to make quantitative extrapolations in the future.