CW operation on APF-IH linac as a heavy ion implanter

In this work we present details of the design and manufacture of a new alternating phase focus-interdigital H (APF-IH) drift tube (DT) linac. Using this apparatus we were able to successfully accelerate He+ ions from 80 up to 193.6 keV. The linac design employs an advanced power-efficiency configuration, APF-IH structure, which has high acceleration efficiency in the low-to-middle energy region. In the design process the relationships between frequency and power, and mesh, end ridge tuner) (ERT, and DT diameter were characterized. The unique aspect of this work is that the fabrication process was not based on direct measurement, which is the traditional design method; instead advanced computer numerical design and simulation methods were employed. A 5-axis numerical control machine was used to fabricate the integral main frame (including acceleration structure, which includes drift tubes, stems, and ridges) without alignment. The experimental results showed that measured values, including the operation frequency, the Q value, the axial electric distribution, and the consumed power for acceleration, were within the design limits; in particular, the measured operation frequency is 99.95% of the design requirement.