The PR-80A has been developed form its original model PR-80, featuring a fully automated beam shaping system for the reduction of charging on wafers. The beam shaping control has been realized by sophisticated integration of such improved components as an ion source, an extraction electrode system, a mass analyzing system, and a machine controller. The ion source and extraction electrode system has been designed to ensure the precise and reproducible settings. The mass analyzing system has a mechanism which automatically adjusts the exit pole-face angle according to an implant recipe. The machine controller sets the beam shape by varying the extraction gap and the arc current, adjusting the normalized perveance of the ion source. The beam shape is monitored by the beam profile monitor. The system is interlocked when a beam has an unacceptable width, peak density, or offset in position. The performance of the PR-80A's endstation is also described.
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