A method for forming thin layers of silicon nitride on substrate surfaces

The invention relates to a method and an apparatus for forming thin layers of silicon nitride on substrate surfaces, wherein the film formation from the gas phase to be made appropriate conditions with the respective atmospheric pressure. According to the task, such layers improved optical properties, mechanical properties and a relatively high purity of the silicon nitride forming the layer should have, and also an increased deposition rate can be achieved. According to the invention while a plasma source for forming plasma is supplied to a polymer formed from an atomic and a molecular gas gas mixture. Ultimately, in the formed and flowing to the respective surface to be coated a plasma precursor mixture containing ammonia, nitrogen and / or argon, and an organic silane element can be supplied. but the respective element organic silane can also be added directly into the plasma source as further precursor. The volume flow for supplied ammonia should be at least 200 times greater than the volumetric flow rate for supplied element organic silane and it is also a relative movement of a device with which the plasma is formed, and the substrate surface to be coated are performed.