  The light absorption of [001] grown single-crystalline silicon wafers can be
enhanced by chemical etching with potassium hydroxide resulting in a
pyramid-like surface texture. Alongside this advantageous property in the
context of solar energy conversion, the surface roughness leads to drawbacks as
well, e.g. difficulties in measuring diffusion behaviour of dopants in the
heterogeneous structure. In this paper, we employ experimental and simulated
scanning transmission electron beam induced current in combination with the
simulation of boron diffusion to map a sub 0.1 ppm isoconcentration line
underneath the textured surface on the nanoscale. In order to account for
surface recombination, an effective two-dimensional model projecting the system
along the electron beam propagation direction is used in the finite elements
EBIC simulation. We find a good agreement to the experimental data and discuss
future strategies to eliminate remaining deviations inside the space charge
region.
