US Patent 7435971 Ion source

An exemplary ion source for creating a stream of ions has an aluminum alloy arc chamber body that at least partially bounds an ionization region of the arc chamber. The arc chamber body is used with a hot filament arc chamber housing that either directly or indirectly heats a cathode to sufficient temperature to cause electrons to stream through the ionization region of the arc chamber. A temperature sensor monitors temperatures within the arc chamber and provides a signal related to sensed temperature. A controller monitors sensed temperature as measured by the sensor and adjusts the temperature to maintain the sensed temperature within a range.