Plasma immersion ion implantation process with chamber seasoning and seasoning layer plasma discharging for wafer dechucking

A method of ion implanting a succession of semiconductor wafers in a plasma reactor, comprising:

• introducing a silicon-containing gas and an oxygen-containing gas into the chamber, generating a deposition plasma in the chamber, and maintaining said deposition plasma until a silicon oxide seasoning layer of a target thickness has been deposited on interior surfaces of said chamber including a wafer support surface of an electrostatic chuck;
• introducing Argon gas into the chamber and generating a conductive discharge plasma in the chamber and maintaining said conductive discharge plasma until residual electrostatic charge in said seasoning layer has been discharged;
• for each one of a succession of semiconductor wafers:
• (a) introducing the semiconductor wafer into the reactor and electrostatically clamping said wafer onto the season layer-covered wafer support surface;
• (b) introducing a semiconductor dopant impurity-containing gas into the chamber and generating an ion implantation plasma in the chamber and maintaining said ion implantation plasma until a desired ion implant dosage has been reached;
• (c) de-chucking said wafer from said wafer support surface and removing said wafer from said chamber;
• (d) repeating (a), (b) and (c) for the next wafer of said succession of wafers;
• after performing (a), (b), (c) and (d) for a predetermined number of wafers, introducing an etchant species-containing gas into said chamber and generating an etch plasma in said chamber and maintaining said etch plasma until said seasoning layer has been removed from said chamber interior surfaces.