Australian Institute of Physics

The model HOLCROSS ion source is designed for the production of high-current and brightness ion beams for application in ion implantation and particle accelerator injection. This ion source has been designed to deliver an ion beam up to a maximum of 30 mA at an energy of 30 keV and will serve as an injector to a radio frequency accelerator. This ion source is equipped with an additional cross-type hollow cathode system placed between the auxiliary plasma generator and the extractor. A negative voltage is applied to the cathode so that dependent low pressure gas discharge (DGD) is observed. High homogeneity and emission density of the plasma (50 mA/cm2) in the extraction region and multiaperture extraction are advantages of this version. The voltage of the DGD has the value 300–1200 V depending on the auxiliary discharge current so the plasma chemical reactions in the extraction region may be controlled. A description of the source is given, together with some recent results.