The main characteristics of analysis by the nuclear method at low energy are summarized. The experimental set-up, and especially the target chamber arrangement are shown. Nuclear analyses of boron and oxygen in a silicon substrate are presented; sensitivity, accuracy and competing reactions have been studied. The analysis of boron and oxygen is possible, although these elements give interfering reactions. Results concerning homogeneity in the sample surface (for diffused or implanted boron), a diffusion study (SiO2−Si exchange) and profile measurements are presented.