Investigation of Silicon Nanowires Produced by Metal-Assisted Chemical Etching Method

Silicon nanowires (SiNWs) have a strong potential in many fields. The investigation of fabrication methods for SiNWs has attracted much attention in semiconductor applications. This paper proposes a metal-assisted chemical etching (MACE) method as a low-cost and simple method for fabrication of SiNWs. This method is based on the electroless metal deposition (EMD) principle. We have studied the conditions of MACE method for fabrication of SiNWs on (100) p-type silicon wafer. A 0.005 AgNO3 and 4.8 M HF solution is used for metal-assisted depositing of the silver nanodots. The etching process is achieved by etchant solution consisting of 4.8 M HF and different concentrations of H2O2. The effect of etching parameters, such as etching time, H2O2 concentration and the dipping time, are investigated. Taguchi with L9 orthogonal array is used by software package MINITAB 17 for designing the experiments. The results of scanning electron microscopy (SEM) observations shows the formation of the silicon nanowires. The effect of the different conditions on the size of the SiNWs is analyzed using S/N ratio and ANOVA approach. The results show that etching time was the most significant factor in the SiNWs fabrication.