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 formed using an acid vapor etching-based method. the porous silicon layer rich in hydrogen and oxygen formed by vapor etching is an excellent passivating agent for the mc-si surface. laser beam-induced current (lbic) analysis of the exponentiation parameter (n) and surface current mapping demonstrates that oxygen and hydrogen-rich porous silicon led to 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 as compared to 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 exponentiation parameter (n) of the lbic versus x-position measurements. these results make achieved porous silicon a good option for advancing efficient photovoltaic cells.