Abstract: An apparatus and method for cathodic magnetron sputtering of a coating onto a temperature-sensitive substrate is disclosed. The apparatus consists of a vacuum chamber having a work-supporting station and a magnetron sputtering target opposite the work-supporting station. The apparatus produces a magnetic field to contain, in an oval pattern, a gas plasma cloud which ejects target material toward the work-supporting station. The temperature of the substrate being coated is controlled by positioning the cooling anode within the sputtering chamber. The position of the cooling anode is adjusted relative to the cathode target to capture primary electrons that would otherwise impinge the substrate. It is in a position with respect to the cathode that does not interfere with the magnetic field.