Ion throughput pump and method

An ion throughput pump (ITP), comprising:

• a pump inlet configured to communicate with a vacuum chamber;
• an ionization source downstream from the pump inlet and the vacuum chamber, the ionization source configured for ionizing gas species received from the vacuum chamber, wherein the pump inlet defines a path for the gas species to enter the ionization source from the vacuum chamber, and wherein the ionization source comprises a magnet assembly;
• a pump outlet;
• ion optics arranged generally along a longitudinal axis of the ITP, and configured for accelerating ions produced by the ionization source toward the pump outlet;
• and
• a roughing pump stage spaced from the pump inlet along the longitudinal axis, the roughing pump stage configured for receiving the ions from the ionization source, producing neutral species from the ions, and pumping the neutral species through the pump outlet, wherein:
• the ionization source defines an ionization region between the pump inlet and the roughing pump stage;
• the ion optics are configured for generating an electric field through the ionization region oriented along the longitudinal axis;
• and
• the magnet assembly is configured to generate a magnetic field that in the ionization region is predominantly oriented in a radial direction orthogonal to the longitudinal axis, such that the ionization source generates a Hall-effect plasma in the ionization region.