Dose monitor for plasma doping system

Plasma doping apparatus comprising:

• a plasma doping chamber;
• a platen mounted in said plasma doping chamber for supporting a workpiece;
• a source of ionizable gas coupled to said chamber, said ionizable gas containing a desired dopant for implantation into the workpiece;
• a pulse source for applying high voltage pulses between said platen and the electrically conductive walls of said chamber for producing a plasma having a plasma sheath in the vicinity of said workpiece, said plasma containing positive ions of said ionizable gas, said high voltage pulses accelerating said positive ions across the plasma sheath toward said platen for implantation into the workpiece;
• and
• a Faraday cup positioned adjacent to said platen for collecting a sample of said positive ions accelerated across said plasma sheath, the sample of said positive ions collected by said Faraday cup being representative of a dose of said positive ions implanted into the workpiece.

Plasma doping apparatus comprising:

• a plasma doping chamber;
• a platen mounted in said plasma doping chamber for supporting a workpiece, said workpiece constituting a cathode;
• an anode spaced from said platen;
• a source of ionizable gas coupled to said chamber, said gas containing a desired dopant for implantation into the workpiece;
• means for producing a plasma containing positive ions of said ionizable gas between said platen and said anode;
• a pulse source for applying high voltage pulses between said platen and said anode for accelerating said positive ions across a plasma sheath of said plasma toward said platen for implantation into the workpiece;
• and
• a Faraday cup positioned adjacent to said platen for collecting a sample of said positive ions accelerated across said plasma sheath, said sample being representative of the dose of positive ions implanted into the workpiece.