Growth and characterization of silicon nanowires catalyzed by Zn metal via Pulsed Plasma-Enhanced Chemical Vapor Deposition

High-density silicon nanowires (SiNWs) were grown via Pulsed Plasma-Enhanced Chemical Vapor Deposition at 400 C. Zinc (Zn) metal thin films with varying thickness from 10 nm to 100 nm were used as a catalyst to synthesize the SiNWs. The surface morphology, crystalline structure, and optical properties of the grown SiNWs were investigated. Results indicated that increasing the Zn thickness from 10 nm to 100 nm led to an increase in wire diameter from 65 nm to 205 nm, resulting in a reduction of SiNW density. The wires grown with Zn thicknesses of 10 and 80 nm exhibited high crystallinity as shown by the X-ray diffraction patterns. Three emission bands (green, blue, and red) were observed in the photoluminescence spectra of the SiNWs prepared using various Zn catalyst thicknesses. The SiNWs prepared using 10 and 80 nm Zn thicknesses displayed a sharp Raman peak that corresponded to the first-order transverse optical phonon mode in contrast to the other samples that produced SiNWs with a broad Raman band.