Figure 3From: Nanofabrication on monocrystalline silicon through friction-induced selective etching of Si3N4 maskLoad effect on friction-induced selective etching of Si/Si 3 N 4 sample. (a) Scratching with progressive load from 0 to 6 mN. (b) Etching in HF solution for 30 min. (c) Further etching in KOH solution for 35 min.Back to article page