THE IMPACT OF SONICATION ON THE STRUCTURE AND PROPERTIES OF STAIN-ETCH POROUS SILICON

The influence of sonication on the surface structure and chemical stab ility of porous silicon (PS) thin films prepared by an open-circuit st ain-etch is described. An analysis of differences in surface morpholog ies by atomic force microscopy between samples prepared either in the presence or absence of sonication reveals that sonication generates a relatively rougher, thicker film as evidenced by the magnitudes of ave rage and root-mean square surface roughness (R(a))and the maximum heig ht of surface features. These differences result in stain-etch porous Si films possessing greater chemical stability to exposure to reagents such as water and organoamines.