SEM images of nanopillars formed from the lightly doped Si after 10-min etching. In (a, b) λ1, (c, d) λ2, (e, f) λ3, and (g, h) λ4 solutions. Panels b, d, f, and h show the cracked nanopillars. These cracks were formed during the breaking of the samples for the SEM investigations.
Wang et al. Nanoscale Research Letters 2013 8:42 doi:10.1186/1556-276X-8-42