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

Figure 7

Pore size distribution (BJH) for measured isotherms of silicon nanowire ensembles which show hysteresis between ad- and desorption branches. The calculated pore volume fraction dV is plotted versus the pore diameters d. The pore size distribution is broadened with longer etching time. Silicon nanowires prepared with  M reveal no pores. (a) Highly doped silicon, preparation parameters: etching time t = 1–3 h and H₂O₂-concentration  M. (b) Highly doped silicon, preparation parameters: etching time t = 1–3 h and H₂O₂-concentration c = 0.2 M.

(a)

(b)