SEM images of nanopillars formed from the highly doped Si in λ3 solution. After etching for 3 min (a, b), 6 min (c, d), and 10 min (e, f), respectively. Panels b, d, and f show the cracked nanopillars. These cracks were formed during breaking of the samples for the SEM investigation. The distance mark in (a) indicates the range of the nanoporous base layer underneath the Au film and the nanopillars.
Wang et al. Nanoscale Research Letters 2013 8:42 doi:10.1186/1556-276X-8-42