An ion implanter includes a source of a stationary, planar ion beam, a set
of beamline components that steer the ion beam along a normal beam path
as determined by first operating parameter values, an end station that
mechanically scans the wafer across the normal beam path, and control
circuitry that responds to a glitch in the ion beam during implantation
pass to (1) immediately alter an operating parameter of at least one of
the beamline components to a second value to direct the ion beam away
from the normal beam path and thereby cease implantation at an
implantation transition location on the wafer, (2) subsequently move the
wafer to an implantation-resuming position in which the implantation
transition location on the wafer lies directly on the normal path of the
ion beam, and (3) return the operating parameter to its first value to
direct the ion beam along the normal beam path and resume ion
implantation at the implantation transition location on the wafer. The
operating parameter may be an output voltage of an extraction power
supply, or other voltages and/or currents of beamline components that
affect the path of the ion beam.