Cross-sectional and temperature-dependent measurements of the electron-beam-induced current reveal the depth profile of the recombination activity of grain boundaries and intragrain dislocations in cast multicrystalline Si. After remote hydrogen plasma treatment for 1 h at 310°C, defects are passivated down to a depth of 100 μm. Even the activity of crystal defects exhibiting small or not detectable room temperature contrast is further reduced by hydrogenation. We interpret the experimental data in terms of a recently developed model, which relates the temperature behavior of the recombination activity to the density of (contaminant-induced) deep levels at the defects. © 2000 American Institute of Physics.