Patent ID: 7806981

Claim:
A device for coating a web material in a single step plasma enhanced chemical vapor deposition process, the device comprising: a vacuum chamber ( 1 ) equipped for maintaining a constant reduced pressure therein and, arranged within the vacuum chamber ( 1 ) are, a rotating drum for supporting and continuously transporting a web material lying against a circumferential surface of the drum, the drum being one of electrically grounded, electrically floating, and negatively biased, more than two independent, substantially identical, magnetron electrodes ( 6 ) comprising: rectangular magnetron faces with a length and a width, a center pole and a peripheral pole, the two poles having opposite polarities and the peripheral pole extending around the center pole, and each magnetron electrode ( 6 ) being powered with an alternating voltage by its own power supply unit ( 7 ), and a plurality of gas supply lines, wherein the magnetron electrodes are arranged with the magnetron faces facing the circumferential surface of the drum and at a same distance therefrom, the lengths of the magnetron faces extending parallel to a drum axis and the widths of the magnetron faces extending substantially tangential to the circumferential surface, and wherein the gas supply lines extend between neighboring magnetron electrodes and comprise rows of gas outlets arranged for gas injection substantially perpendicular to the circumferential drum surface, wherein the magnetron faces and the gas supply lines are arranged side by side to form, together with a part of the circumferential surface of the rotating drum, one baffle-free combined process space and wherein the gas supply lines are connected to a source of only one process gas mixture.