Multicrystalline Silicon Passivation by Hydrogen and Oxygen-Rich Porous Silicon Layer for Photovoltaic Cells Applications

In this work, we demonstrate the beneficial effect of introducing a superficial porous silicon layer on the electronic quality of multi-crystalline silicon for photovoltaic cell application. The porous silicon was prepared using an acid vapor etching-based method. The porous silicon layer rich in hydrogen and oxygen formed by vapor etching using an excellent passivating agent for the mc-Si surface. Laser beam-induced current (LBIC) analysis of the exponent parameter (n) and surface current mapping demonstrated that oxygen and hydrogen-rich porous silicon led to an excellent surface passivation with a strong electronic quality improvement of multi-crystalline silicon. It was found that the generated current of treated silicon by acid vapor etching-based method is 20 times greater than the reference substrate, owing to recombination centers passivation of the grains and grain boundaries (GBs); The actual study revealed an apparent decrease in the recombination velocity of the minority carrier as reflected by 25% decrease in the exponent parameter (n) of the LBIC versus X-position measurements. The results obtained for the prepared porous silicon in this study indicates its possible use in a more efficient photovoltaic cell applications.