Optics and Photonics Society of Iran

In this paper, we report an ultrasensitive surface enhanced raman spectroscopy (SERS) substrate based on Ag modified silicon nanowires (SiNWs). For this aim, SiNWs are fabricated using the vapor-liquid-solid (VLS) growth mechanism and decorated with Ag nanoparticles (NPs) by means of electroless deposition method. This process provides the possibility of forming uniformly and tightly packed Ag NPs on SiNWs. First, the influence of Ag NPs deposition time on SERS activity of substrates is explored to achieve maximum signal enhancement factor (EF). In the following, capability of our nanostructure is assessed for different concentration and subsequently, limit of detection (LOD) 10 pico molar with EF of 1.5×10⁹ is obtainedd.