Simulation of hydrogen penetration into p-type silicon under wet chemical etching

Penetration of hydrogen into p-Si and formation of hydrogen-containing defects under wet chemical etching were simulated. The simulated concentration profiles of hydrogen-containing defects were compared to the measured profiles. It is shown that the hydrogen-distribution relaxation after termination of etching is important in the crystals with a low trap concentration. Consideration of such relaxation makes it possible to describe all experimental profiles without assuming that the hydrogen diffusivity is anomalously high. However, the experimental profiles can also be described assuming that the hydrogen diffusivity is high, with the effect of relaxation being less important in this case. It is shown that a comparative analysis of concentration profiles for the hydrogen-containing centers makes it possible to determine the number of hydrogen atoms in these centers in the cases where these profiles are either formed mainly in the course of etching or are modified significantly by transient hydrogen diffusion.