Extraction electrode assembly voltage modulation in an ion implantation system

A method for reducing particle contamination in an ion implantation system, the method comprising the steps of:

• providing an ion implantation system comprising:
• an ion source;
• an extraction electrode assembly situated proximate to the ion source, said extraction electrode assembly including a suppression electrode and a ground electrode separated by ceramic insulators for electrically isolating the suppression electrode and the ground electrode;
• and
• an end station configured to transfer workpieces into and out of the end station for selective implantation of ions into the workpieces;
• forming an ion beam via the ion source operating in conjunction with the with the extraction electrode assembly proximate to the ion source, whereby a cathode voltage is applied to the ion source for generating ions therein, and a suppression voltage is applied to the extraction electrode assembly proximate to the ion source for preventing electrons in the ion beam from being drawn into the ion source;
• exchanging the workpieces between the end station and an external environment such that, once sufficient implantation of ions is complete, a treated workpiece is transferred from the end station into an external environment, and an untreated workpiece is transferred from the external environment into the end station for implantation of ions;
• and
• modulating the suppression voltage applied to the extraction electrode assembly proximate to the ion source generally concurrent with the exchanging step whereby treated workpieces are transferred from the end station into an external environment, and the untreated workpieces are transferred from the external environment into the end station for implantation of ions, thereby inducing a current flow through the ceramic insulators of the extraction electrode assembly during the exchange step to remove deposits on surfaces of the extraction electrode assembly and to mitigate subsequent contamination of workpieces.