The invention relates to a method for producing a TaNx diffusion barrier layer with 0.5 < x < 1.67, wherein tantalum nitride or a tantalum nitride-tantalum cement having a density of > 99 of the theoretical density is used as evaporator source. Part of the reactive gas in the process gas is reduced to a minimum by using ceramic tantalum nitride or tantalum nitride-tantalum cement evaporator sources. One part of < 20 vol. % of the reactive gas component is typically sufficient in order to compensate losses by pumping off the gaseous components of the compound during the evaporation and condensation process of the layer material.
