摘要 |
An ion beam implantation system utilizing two pairs of mutually orthogonal scanning electrodes. Two sawtooth waveforms of approximately the same frequency are applied to the scanning electrodes to produce four sided scanning patterns. The dimensions of these scanning patterns are varied to sweep out a scan pattern that uniformly implants a circular wafer. By perturbing the scanning voltages the instantaneous beam speed is adjusted to compensate for small dose nonuniformities.
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