Patent EP-2599891-A2 (EP)
Inventor: RAMM JUERGEN
IPC: C23C14/32
Filed: 2007-07-12
Abstract: The method for the production of insulating layers on workpiece by vacuum coating, comprises operating an electrical arc discharge between anode and cathode of an arc source in an atmosphere containing reactive gas and producing a small external magnetic field at the surface of a target electrically connected to the cathode perpendicular to the target surface. The magnetic field comprises perpendicular component and smaller radial or surface-parallel component for the support of vaporization process. The magnetic system is arranged in a plane, which is present behind the target surface. The method for the production of insulating layers on workpiece by vacuum coating, comprises operating an electrical arc discharge between anode and cathode of an arc source in an atmosphere containing reactive gas and producing a small external magnetic field at the surface of a target electrically connected to the cathode perpendicular to the target surface. The magnetic field comprises perpendicular component and smaller radial or surface-parallel component for the support of vaporization process. The magnetic system is arranged in a plane, which is present behind the target surface. The magnetic field is generated by a magnet system that comprises axially polarized coil with geometry similar in size to the target, which is subjected with an exciting current. The perpendicular component at the target surface is adjusted in a range between lesser 25 Gauss. The spark discharge or/and an arc source is supplied with an equal flow and with a pulse- and/or an alternating current. An increase of the direct current-portion of the source voltage of 20% is caused by an insulating allocation of the target surface in relation to the operation with a surface without insulating allocation. A pulse current supply is operated between the cathode of an arc source as first electrode and the second electrode arranged separately from the arc source. The second electrode is operated as cathode of another arc source and is connected with a direct current supply. A sputtering cathode is switched as the second electrode. Two targets are operated in arrangements that lie opposite to each other and the workpiece is arranged between the targets. The exciting current is the direct current and/or the pulse current and/or alternating current that is led by the power source via coil to the cathode. The coil is laid out so that the exterior magnetic field adjusts itself with flowing of the exciting current to the value of the self magnetic field of the electric arc of current. The coil with a coil number is used between 1-5 windings. The reactive gas comprises oxygen, and an oxide is separated from oxide containing layer. Adhesive and/or hard layer is applied on the workpiece of the oxide-containing layer. Adhesive layer, hard layer and/or oxide layers of a transitional layer are applied, that contains the elements of the two directly sequenced successive layers. The degree of recoating of the surface by other coating sources is 10% less than the metal quantity evaporated from the cathode. Electrical insulator limitation ring is arranged that consists either of an electric insulator or good conducting metal.