CHANGES IN THE CREATION OF POINT-DEFECTS RELATED TO THE FORMATION OF POROUS SILICON

A theoretical study of the evolution of point defects in the first stages of porous silicon formation by anodizing of crystalline silicon in a hydrofluoric acid solution is reported. A model of interactions between intrinsic point defects and impurities in the near-surface region of semiconductors during formation of pores is proposed. It is shown that a redistribution of defects and the formation of areas with different concentrations of vacancy-type defects may be the reason for formation of a porous structure. The generation rate of vacancies due to reactions of the silicon surface states with the HF acid as a function of main parameters of the system, such as the concentration of holes, the HF concentration, and the anodic current, is presented.