Study Of Extraction Property Of Rf Ion Source

Effects of geometry parameters of extraction electrode, extraction voltage and oscillator power on the extraction property of RF ion source are measured and the experimental results are analyzed. It turns out that the RF ion source has a good extraction property. There is the best D/d on condition that other parameters don't change. The D/d rising is beneficial to the ion beam focusing from over focusing. Focusing degree increases and extraction beam intensity drops with b/D increasing. Focusing degree rises with B/d decreasing and the rising tendency slows down when B/d is smaller than 4. The suitable ranges of D/d, b/D and B/d are respectively 1.6-2.1, 0.7-1.1 and 4-7 when considering comprehensively the focusing degree, the extraction beam intensity and the pressure. Change of extraction voltage and oscillator power has opposite effect on the ion source performance and they have respectively best operation values.