Abstract: In a process for treating a surface with the aid of a glow discharge plasma sustained in a gas of substantially ambient pressure between two electrodes (10, 10?) unwanted effects of plasma filaments occurring in such a plasma are prevented by positioning the surface (17) to be treated in an edge region (14?) of the plasma. The surface is placed on one side of a plasma space (14) defined by the electrode faces (11, 11?) beyond a pair of aligned edges (13, 13?) of the electrode faces (11, 11?), at a distance of a few millimeters from these edges (13, 13?), and facing these edges (13, 13?). The treatment gas or treatment gas mixture is fed to the plasma space (14) from a second side opposite the edge region (14?) in which the surface (17) to be treated is positioned. During treatment, a substrate (16) whose one surface (17) is to be treated is either stationary or is advanced in a direction substantially perpendicular to the electrode faces (11, 11?).

Abstract: In a process for treating a surface with the aid of a glow discharge plasma sustained in a gas of substantially ambient pressure between two electrodes (10, 10′) unwanted effects of plasma filaments occurring in such a plasma are prevented by positioning the surface (17) to be treated in an edge region (14′) of the plasma, i.e. on one side of a plasma space (14) defined by the electrode faces (11, 11′) beyond a pair of aligned edges (13, 13′) of the electrode faces (11, 11′), at a distance of a few millimeters from these edges (13, 13′) and facing these edges (13, 13′). The treatment gas or treatment gas mixture is fed to the plasma space (14) from a second side opposite the edge region (14′) in which the surface (17) to be treated is positioned. During treatment a substrate (16) whose one surface (17) is to be treated is either stationary or is advanced in a direction substantially perpendicular to the electrode faces (11, 11′), e.g.