Numerous methods have been developed

to fabricate SiNWs including bottom-up or top-down technologies, such as vapor-liquid–solid growth [9, 10], solid–liquid–solid growth [11, 12], reactive ion etching [13], or metal-assisted chemical etching (MACE) [14]. Compared with the other techniques, the MACE is a simple and low-cost method MDV3100 purchase offering better structure controllability of silicon nanowire such as diameter, length, orientation, morphology and porosity, which, therefore, has attracted increasingly research interests in the past decade [5, 14, 15]. In principle, the MACE process includes two successive steps, the nucleation of metal catalysts and anisotropic etching, which are classified as the one-step and two-step MACE, respectively [16]. In the one-step MACE (1-MACE), the two processes take place

in an etching solution containing HF and metal salts. In the two-step MACE (2-MACE), metal catalysts are firstly deposited on the wafer surface, and the subsequent anisotropic etching occurs in the HF/oxidant (oxidant = H2O2[17, 18], Fe(NO3)3[19, 20] or KMnO4[21], etc.) solution. Recently, the fabrications of one-dimensional silicon nanowires with porous structure using the MACE method have been given more wide attention. The emerging mesoporous silicon nanowires (MPSiNWs) open a new door to develop the wide applications derived from the enhanced surface areas and quantum confinement effect [22]. The doped type and concentration, fabrication methods and etching temperature have an important effect on the morphology of silicon nanowire. Yang et al. [23] have reported that the MPSiNWs were fabricated by 1-MACE with highly doped p-type selleck inhibitor silicon at temperature of 25°C to 50°C. To et al. [22] reported that the MPSiNWs were also obtained by etching highly doped n-type silicon with the 1-MACE method. In addition, the 2-MACE was also often reported to fabricate PSiNWs [24–27]. In general,

it has been found that the roughness of silicon nanowires is increased with Capmatinib increasing Edoxaban doped level and H2O2 concentration [24, 28]. For both MACE, the lightly doped silicon wafers are often difficult to obtain PSiNWs [22–27]. In the present work, the H2O2 oxidant was introduced into HF/AgNO3 etching solution for fabricating PSiNWs, which might be called ‘one-pot procedure’ MACE, it is practicable method for fabricating PSiNWs, even for lightly doped ones. The effect of doped level on nanostructure of SiNWs was studied. Meanwhile, the effects of H2O2 concentration on nanostructure of lightly doped SiNWs were also investigated. According to the experiment results, a model was proposed to describe the pore formation process. Methods The moderately and lightly doped p-type Si(100) wafers with resistivity of 0.01 ~ 0.09 and 10 ~ 20 Ωcm were respectively selected as the starting wafer. Prior to etching, the wafers were cut into 1 × 1 cm2, and then were cleaned by ultrasonication in acetone, ethanol, and deionized water, respectively.