Abstract: Method and apparatus for holding a wafer having a wafer dimension during processing, the vacuum chuck comprising a concave wafer platen configured force the wafer into intimate contact with the wafer platen and provide a seal therebetween when high pressure is applied to the wafer. The wafer platen for preventing matter from entering between the wafer and vacuum chuck. A groove configured in the wafer platen applies vacuum to the underside of the wafer. A plenum configured in the platen provides pressure for a predetermined amount of time between the wafer and the vacuum chuck to disengage the wafer.

Abstract: A method and apparatus are provided which increase the collimation of sputter deposited films by increasing the mean free path (MFP) of sputtered atoms so as to reduce redirecting collisions with the buffer gas. This is accomplished by reducing buffer gas pressure while employing mechanisms to maintain or increase plasma electron density so as to sustain the plasma in the absence of normally required gas pressure. A first mechanism used to permit reduced gas pressure is to provide gas flow directly to the immediate region of the plasma discharge rather than to another remote area of the sputter deposition chamber. A second mechanism used to permit reduced gas pressure is to provide an electron emitting source near the plasma discharge to increase the plasma electron density without requiring further ionization of buffer gas atoms. These two mechanisms can be used either alone or together, as desired, in view of the circumstances presented.