Patent ID: 7804040

Claim:
A physical vapor deposition reactor, comprising: a vacuum chamber including a sidewall, a ceiling and a retractable wafer support pedestal near a floor of the chamber, and a vacuum pump coupled to the chamber, said retractable wafer support pedestal having an internal electrode and a grounded base with a conductive annular flange extending from said base, said base and said flange being retractable with said pedestal; a process gas inlet coupled to said chamber, said process gas inlet capable of being coupled to a process gas source; a metal sputter target adjacent said ceiling, said metal sputter target capable of being coupled to a D.C. voltage source; an RF plasma source power generator coupled to said metal sputter target and having a frequency suitable for exciting kinetic electrons; a removable shield adjacent said sidewall and plural compressible conductive tabs dispersed at generally uniform intervals on said annular flange and in contact with a bottom edge of said shield whenever said retractable wafer support pedestal is in an unretracted position, each of said uniform intervals being less than a wavelength corresponding to the frequency of said RE plasma source power generator; and wherein each of said compressible conductive tabs comprises a hollow cylinder formed of a metal layer and has a cylindrical axis parallel to a workpiece support plane of said workpiece support pedestal.