Controlled Pore Formation on Mesoporous Single Crystalline Silicon Nanowires: Threshold and Mechanisms

Figure 1

Scanning electron micrograph of silicon nanowire ensembles from (a) undoped silicon (100) ( Ωcm)  M,  M, etching time 180 min. There are long solid wires (about 110 μm) on both sides of the thin (<90 μm) remaining silicon substrate. (b) Highly boron-doped silicon (100) ( Ωcm)  M,  M, etching time 180 min. The wires form bundles and lie near against each other. The nanowire tips are bent to the tips of the neighboring nanowires, indicating smaller diameters and pore formation. (c) Large scales of uniform silicon nanowire standing on the wafer in cross sectional view.

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