Ion source using field emitter array cathode and electromagnetic confinement

摘要

An ion source for use in a radiation generator tube includes a back passive cathode electrode, a passive anode electrode downstream of the back passive cathode electrode, a magnet adjacent the anode, and a front passive cathode electrode downstream of the passive anode electrode. The front passive cathode electrode and the back passive cathode electrode define an ionization region therebetween. At least one field emitter array (FEA) cathode is configured to electrostatically discharge due to an electric field in the ion source. The back passive cathode electrode and the passive anode electrode, and the front passive cathode electrode and the passive anode electrode, have respective voltage differences therebetween, and the magnet generating a magnetic field, such that a Penning-type trap is produced to confine electrons from the electrostatic discharge to the ionization region. At least some of the electrons in the ionization region interact with an ionizable gas to create ions.

主权项

1. An ion source for use in a radiation generator tube comprising:
a back passive cathode electrode; a passive anode electrode downstream of the back passive cathode electrode; a magnet adjacent the anode; a front passive cathode electrode downstream of the passive anode electrode, the front passive cathode electrode and the back passive cathode electrode defining an ionization region therebetween; at least one field emitter array (FEA) cathode, spaced apart from the back passive cathode electrode, the passive anode electrode, and the front passive cathode electrode, and configured to electrostatically discharge due to an electric field in the ion source; the back passive cathode electrode and the passive anode electrode, and the front passive cathode electrode and the passive anode electrode, having respective voltage differences therebetween, and the magnet generating a magnetic field, such that a Penning-type trap is produced to confine electrons from the electrostatic discharge to the ionization region; at least some of the electrons in the ionization region interacting with an ionizable gas to create ions.