Resonator, linear accelerator, and ion implanter having adjustable pickup loop

A method of controlling a resonator in a linear accelerator, comprising:

• generating an RF input signal at an exciter, disposed within a resonance chamber;
• generating an RF output signal in a resonator coil, disposed within the resonator chamber, based upon the RF input signal;
• detecting the RF output signal at a pickup loop assembly, the pickup loop assembly comprising a variable attenuator, having a configurable portion;
• outputting a pickup voltage signal based upon the RF output signal, the pickup voltage signal having a voltage value within a determined range;
• and
• adjusting a position of the variable attenuator from a first position, attenuating a first amount of the RF output signal, to a second position, attenuating a second amount of the RF output signal, based upon the voltage value.

An ion implanter, comprising:

• an ion source to generate an ion beam;
• and
• a linear accelerator, including at least one acceleration stage to accelerate the ion beam, wherein the at least one acceleration stage comprises:
• an exciter, disposed within a resonance chamber, to generate an RF power signal;
• a resonator coil, disposed within the resonance chamber, to receive the RF power signal, and generate an RF output signal;
• and
• a pickup loop assembly, to receive the RF output signal and output a pickup voltage signal, the pickup loop assembly comprising;
• a pickup loop, disposed within the resonance chamber;
• and
• a pickup loop container, disposed around the pickup loop, wherein the pickup loop container comprises a conductive shell and an aperture, the conductive shell blocking a first portion of the RF output signal, and the aperture transmitting a second portion of the RF output signal to the pickup loop.