NOVELTY - The method comprises positioning a working chamber (2) with a plasma torch (4), producing a plasma beam (5), in which a plasma gas is guided by the plasma torch and is heated by an electrical gas discharge, an electromagnetic induction and/or microwaves, guiding the plasma beam to a substrate (3) introduced in the working chamber, injecting a reactive component in liquid or gaseous form into the plasma beam and/or injecting the reactive component into the free plasma beam to treat a surface of the substrate to be coated and/or treated, and producing a layer or a coating.    USE - Method for coating and/or treating the surfaces of substrates using a plasma beam, where the substrate is useful for semiconductors such as solar cells.    ADVANTAGE - The method is capable of effectively coating and/or treating the surfaces of the substrates with high mechanical resistance, high chemical resistance, high corrosion resistance and high quality.    DETAILED DESCRIPTION - The method comprises positioning a working chamber (2) with a plasma torch (4), producing a plasma beam (5), in which a plasma gas is guided by the plasma torch and is heated by an electrical gas discharge, an electromagnetic induction and/or microwaves, guiding the plasma beam to a substrate (3) introduced in the working chamber, injecting a reactive component in liquid or gaseous form into the plasma beam and/or injecting the reactive component into the free plasma beam to treat a surface of the substrate to be coated and/or treated, and producing a layer or a coating and/or treating the surface of the substrate, so that the produced layer or coating or the treated substrate has a thickness of 0.01-10 mu m. The plasma torch has a capacity to thermally plasma-injecting the solid particles. The pressure in the working chamber during the process is 0.05-2 mbar. The plasma torch has a maximum capacity of 30kW, 50 kW or 70 kW and/or 20-150 kW. Additional coating material is introduced into the plasma beam in the form of powder-like solid or in the form of suspension. The produced layer or coating or the treated surface of the substrate has a porosity of 0.02-2%. INDEPENDENT CLAIMS are included for:    (1) a method for producing a coating with two layers of different structure;    (2) a substrate or a workpiece with a layer; and    (3) a plasma coating plant.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic representation of a plasma coating plant.    Plasma coating plant (1)    Working chamber (2)    Substrate (3)    Plasma torch (4)    Plasma beam (5)    Substrate holder. (8)