Thin films of Si₃N₄ were prepared by non-reactive magnetron sputtering in an Ar atmosphere. A previously synthesized Si₃N₄ was used as a solid-state target. Deposition was carried out on a cold substrate of p-Si (100) with a resistivity of 2Ohmcm. The Raman spectrum of the deposited Si₃N₄ layers has been investigated. The position of the maximum in the Raman scattering spectrum of Si₃N₄ layers corresponds to the Si₃N₄ compound and the shape of the spectrum is characteristic for the nanocrystalline state of the cubic modification of silicon nitride.The film thickness has been determined from atomic force microscopy measurements. The results of electron diffraction investigations of n-Si₃N₄ nanolayers with thicknesses up to 20nm demonstrates that as-deposited Si₃N₄ thin films consist of a mixture of microcrystalline and amorphous phases.Solar cells based on heterostructures consisting of a p-type Si (100) and n-type Si₃N₄ nanolayers were fabricated and studied.