Nassiopoulou et al. Nanoscale Research Letters 2011, 6:597 http://www.nanoscalereslett.com/content/6/1/597 Page 4 of 8 Figure 2 SEM images of SiNWs grown along the three equivalent crystallographic orientations. SiNWs on different (100)-equivalent crystallographic orientations: (a) front side of the wafer, (b) wafer edges, and (c) back side of the wafer. The backside wafer surface is rough, and this roughness is reproduced on the SiNW surface since the NW length stays constant all along the surface. Figure 3 A schematic representation and SEM images of SiNWs formed on the confined area. (a, b, c) show the process flow for SiNW formation by MACE on the confined areas, while (d) depicts top-view SEM images of the etched confined areas. In (e) and (f), we see examples of cross-sectional SEM images of the SiNWs. The edge of the etched area is illustrated in (f), depicting that the etching process is relatively anisotropic.