One-step synthesis of lightly doped porous silicon nanowires in HF/AgNO{sub 3}/H{sub 2}O{sub 2} solution at room temperature
One-step synthesis of lightly doped porous silicon nanowire arrays was achieved by etching the silicon wafer in HF/AgNO{sub 3}/H{sub 2}O{sub 2} solution at room temperature. The lightly doped porous silicon nanowires (pNWs) have circular nanopores on the sidewall, which can emit strong green fluorescence. The surface morphologies of these nanowires could be controlled by simply adjusting the concentration of H{sub 2}O{sub 2}, which influences the distribution of silver nanoparticles (Ag NPs) along the nanowire axis. A mechanism based on Ag NPs-induced lateral etching of nanowires was proposed to explain the formation of pNWs. The controllable and widely applicable synthesis of pNWs will open their potential application to nanoscale photoluminescence devices. - Graphical abstract: The one-step synthesis of porous silicon nanowire arrays is achieved by chemical etching of the lightly doped p-type Si (100) wafer at room temperature. These nanowires exhibit strong green photoluminescence. SEM, TEM, HRTEM and photoluminescence images of pNWs. The scale bars of SEM, TEM HRTEM and photoluminescence are 10 {mu}m, 20 nm, 10 nm, and 1 {mu}m, respectively. Highlights: Black-Right-Pointing-Pointer Simple one-step synthesis of lightly doped porous silicon nanowire arrays is achieved at RT. Black-Right-Pointing-Pointer Etching process and mechanism are illustrated with etching model from a novel standpoint. Black-Right-Pointing-Pointer As-prepared porous silicon nanowire emits strong green fluorescence, proving unique property.