A novel passivation process of silicon nanowires by a low-cost PECVD technique for deposition of hydrogenated silicon nitride using SiH 4 and N 2 as precursor gases

. In this work, a different SiN x passivation process of silicon nanowires has been opted for the deposition of a hydrogenated silicon nitride (SiN x :H) by a low-cost plasma enhanced chemical vapor deposition (PECVD) using silane ( SiH 4 and nitrogen ( N 2 as reactive gases. This study is focused on the effect of the gas flow ratio on chemical composition, morphological, optical and optoelectronic properties of silicon nanowires. The existence of Si-N and Si-H bonds was proven by the Fourier transmission infrared (FTIR) spectrum. Morphological structures were shown by scanning electron microscopy (SEM), and the roughness was investigated by atomic force microscopy (AFM). A low reflectivity less than 6% in the wavelength range 250-1200nm has been shown by UV-visible spectroscopy. Furthermore, the thickness and the refractive index of the passivation layer is determined by ellipsometry measurements. As a result, an improvement in minority carrier lifetime has been obtained by reducing surface recombination of silicon nanowires.