Application of digital frequency and phase synthesis for control of electrode voltage phase in a high-energy ion implantation machine, and a means for accurate calibration of electrode voltage phase

摘要

An improved HE LINAC-based ion implantation system is disclosed utilizing direct digital synthesis (DDS) techniques to obtain precise frequency and phase control and automated electrode voltage phase calibration. The DDS controller may be used on a multi-stage linear accelerator based implanter to digitally synchronize the frequency and phase of the electric fields to each electrode within each stage of the accelerator. The DDS controller includes digital phase synthesis (DPS) circuits for modulating the phase of the electric field to the electrodes, and a master oscillator that uses digital frequency synthesis or DFS to digitally synthesize a master frequency and phase applied to each of the DPS circuits. Also disclosed are methods for automatically phase and amplitude calibrating the RF electrode voltages of the stages.