US 7,498,586 B2
	Ion source control system
Wayne Sainty, Sydney (Australia); and William Vince Waller, Wyoming (Australia)
Assigned to Saintech Pty, Ltd., Sydney (Australia)
Appl. No. 10/577,421 PCT Filed Aug. 13, 2004, PCT No. PCT/AU2004/001082 § 371(c)(1), (2), (4) Date Apr. 27, 2006, PCT Pub. No. WO2005/045874, PCT Pub. Date May 19, 2005.
Claims priority of application No. 2003906001 (AU), filed on Oct. 31, 2003.
Prior Publication US 2007/0089980 A1, Apr. 26, 2007
Int. Cl. H01J 27/02 (2006.01)

U.S. Cl. 250—423R  [250/492.21; 250/492.1; 250/427; 250/492.2; 250/493.1; 250/424; 250/426; 313/362.1; 315/111.01; 315/111.21; 315/111.81; 315/111.91]

30 Claims

1. A method of operating an ion source comprising providing a voltage signal to an anode at a first end of an ionization region of the ion source, providing a signal to a gas supply of the ion source to cause gas to be provided to the ionization region, providing a signal to a cathode at a second end of the ionization region opposite the first end to cause electrons to be emitted by the cathode such that electrons emitted by the cathode are accelerated through the ionization region toward the anode to cause ionization of the gas, thereby producing an ion current, wherein the anode voltage signal comprises a voltage that accelerates ions of the ion current out of the second end of the ionization region and that modulates between a first voltage above a threshold and a second voltage below the threshold.