Influence of final treatment on the incubation period and antireflection properties of stain-etched porous silicon



The influence of composition of various solutions, applied for final treatment of Si wafers before stain-etched porous silicon (PS) formation, on the incubation period and antireflective properties has been investigated. PS layers were obtained by chemical etching in HF:HNO3:CH3COOH modified solution at oxidant insufficiency. It is shown that the minimum incubation period and the reflectivity correspond to the final treatment of wafers in undiluted HF. Studies of reflection spectra have shown the possibility of smooth adjustment of the minimum in the reflection spectra, which is of interest for the formation of antireflection coating for solar cells.