Patent ID: 8500973

Claim:
A sputtering apparatus for use in the sputtering of a material, comprising: a cathode electrically coupled to a voltage source; at least one anode defining a substantially closed vessel comprising one or more sidewalls and a bottom wall, said vessel having an opening to an electrically conductive inner body and having an outer body, wherein the inner and outer body are at a same electrical potential and are formed of the one or more sidewalls and bottom wall, such that the inner body is the inside one or more sidewalls and bottom wall of the vessel and an outside one or more sidewall forms the outer one or more sidewalls and outer bottom wall of the vessel, wherein the electrically conductive inner body is coupled to the voltage source for providing a voltage difference between the sputtering material and the conductive inner body, wherein the inner body of the vessel is for receiving and collecting electrons or negatively charged particles passing through the opening, wherein the opening to the electrically conducting inner body is so located for communicating with a coating chamber and wherein the anode is electrically isolated from the coating chamber, wherein the opening of the vessel is polygonal shaped, wherein the cathode is negatively biased and wherein the anode is positively biased, the cathode and the anode forming a part of a same electrical circuit; wherein the opening is at one end or side face thereof, for communicating with a coating chamber and for allowing charged particles to flow between the electrically conductive inner body and the cathode external to the anode and within the coating chamber, and wherein the opening is at least two inches from a cathode within the coating chamber to facilitate a uniform pressure distribution over a target area, wherein the cathode is not within or encircled by the anode; and wherein the opening has a diameter or largest opening length of “a” and wherein the opening is a distance “d” from the cathode, and wherein an angle α=arctan (a/d) and wherein α<90 degrees.