System and method for improved beam current from an ion source

An IHC ion source that employs a negatively biased cathode and one or more side electrodes is disclosed. The one or more side electrodes are left electrically unconnected in certain embodiments and are grounded in other embodiments. The floating side electrodes may be beneficial in the formation of certain species. In certain embodiments, a relay is used to allow the side electrodes to be easily switched between these two modes. By changing the configuration of the side electrodes, beam current can be optimized for different species. For example, certain species, such as arsenic, may be optimized when the side electrodes are at the same voltage as the chamber. Other species, such as boron, may be optimized when the side electrodes are left floating relative to the chamber. In certain embodiments, a controller is in communication with the relay so as to control which mode is used, based on the desired feed gas.