The structural, optical and electrical aspects of as deposited as well as annealed amorphous hydrogenated silicon nitride
(a-SiNx: H) thin films of different stoichiometry, grown on silicon wafer by radio frequency- plasma enhanced chemical vapor deposition (RF-PECVD) are thoroughly investigated. Photoluminescence (PL) measurement verify that Si rich a-SiNx: H (SRSN) film of refractive index 2.68, gives good PL as compared to near stoichiometric film and support the presence of Silicon quantum dots (Si QDs) embedded in a-SiNx: H matrix. Detailed structural analysis by high resolution transmission electron microscopy (HRTEM) revealed that as deposited SRSN thin film contains amorphous Silicon quantum dots (a-Si QDs) which are grown by phase separation of SRSN film during the synthesis process. These SRSN thin films of different thicknesses have been deposited at the surface of Silicon solar cell as anti-reflection coatings (ARCs). By reflectance measurement, it is observed that the ARC contains a-Si QDs in a-SiNx: H matrix, more effectively minimize the reflection of incident light across the wavelengths ranging from 300 to 800 nm. With a-Si QDs/ a-SiNx: H ARC, we demonstrate an increase in short circuit current density, open circuit voltage and conversion efficiency by 4.34 mA/cm2, 0.01V and 0.21% (absolute) respectively and indicate its utility in improving the performance of Si solar cells. Copyright © 2017 VBRI Press.