The invention relates to a device for treating the surface of a substrate by means of dielectric barrier discharge for generating a filamentary plasma, including a reaction chamber comprising a mixture having a composition such that, when in contact with the plasma, the mixture decomposes and generates species capable of deposition in the form of a layer mostly or totally on the substrate, wherein at least two electrodes area provided in said chamber, with one electrode being subjected to a high AC voltage, and are arranged on either side of the substrate, at least one dielectric barrier (DBD) arranged between said at least two electrodes, and a THT/HF transformer comprising a secondary circuit, in which a direct current (DC) power source is provided in series in the secondary circuit such that the chemical species generated in the plasma in the form of electrically positive or negative ions are selectively attracted by the target substrate inserted in the reaction chamber and arranged between said at least two electrodes, and repelled by electrodes having a corresponding charge.