Radio frequency-driven proton source with a back-streaming electron dump

Q Ji; A Sy; J W Kwan

doi:10.1063/1.3267832

Radio frequency-driven proton source with a back-streaming electron dump

Rev Sci Instrum. 2010 Feb;81(2):02B312. doi: 10.1063/1.3267832.

Authors

Q Ji¹, A Sy, J W Kwan

Affiliation

¹ Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 5R0121, Berkeley, California 94720, USA. qji@lbl.gov

PMID: 20192435
DOI: 10.1063/1.3267832

Abstract

This article describes an rf ion source with a back-streaming electron dump. A quartz tube, brazed to a metal plug at one end, is fused in the center of a flat quartz plate. rf power (at 13.6 MHz) is coupled to generate hydrogen plasma using a planar external antenna bonded to the window. Bonding the water-cooled rf antenna to the quartz window significantly lowers its temperature. The water-cooled metal plug serves as the back-streaming electron dump. At 1800 W, the current density of extracted hydrogen ions reaches approximately 125 mA/cm(2).