Microstructure of pores in n+ silicon

Abstract The structure of pores in n −1 /n + /n − silicon structures has been studied by cross-section transmission electron microscopy. Under the experimental conditions examined, the pore directions in the n + layer follow the current path and do not show crystallographic preference. Stray pores were observed in the n − layer and they appear to grow along 〈100〉 directions. By using cross sections transverse to the pore length, we have obtained end-on views that show that the pore walls tend to facet along {111} planes. We have also observed wafer surface faceting on {113} planes as a result of the anodization process.