Boron distribution for PLIE samples: (a) one-dimensional boron depth distribution calculated by integrating the data of Figure 3 over a 10 nm radius cylindrical from the two volumes of Figure 3 and boron depth measured by secondary ion mass spectrometry (SIMS) for 3 at.% of B. (b) Example of distribution of the boron content (histogram) in sets of 200 atoms located in a 30 × 30 × 10 nm³ data slice of 9 at.% boron compared to a binomial distribution.