US 7,989,784 B2 · Ion implantation apparatus and a method

Abstract

A hydrogen ion implanter for the exfoliation of silicon from silicon wafers uses a large scan wheel carrying 50+ wafers around its periphery and rotating about an axis. In one embodiment, the axis of rotation of the wheel is fixed and a ribbon beam of hydrogen ions is directed down on a peripheral edge of the wheel. The ribbon beam extends over the full radial width of wafers on the wheel. The beam is generated by an ion source providing an extracted ribbon beam having at least 100 mm major cross-sectional diameter. The ribbon beam may be passed through a 90° bending magnet which bends the beam in the plane of the ribbon. The magnet provides intensity correction across the ribbon to compensate for the dependency on the radial distance from the wheel axis of the speed at which parts of the wafers pass through the ribbon beam.

Claims27

Dependent claims

Ion implantation apparatus for performing an ion implantation process to implant ions into multiple planar workpieces, the apparatus comprising:

a workpiece support wheel mounted for rotation about an axis which is translationally fixed during a said implantation process, said support wheel having a plurality of workpiece supports distributed at a common radius around a periphery of said wheel;
and
an ion beam generator which is arranged to form, during said implantation process, a non-scanning beam of ions for implanting, said beam being directed along a beam path to an implant location on said wheel periphery, whereby said workpieces on said supports are passed successively through said implant location along a circular scan path by rotation of said wheel, said workpieces each having a predetermined linear dimension in a plane of said workpiece, said predetermined linear dimension extending normal to said scan path when said workpieces are mounted on said supports, and said ion beam generator being adapted such that at said implant location, said beam of ions has a cross-sectional dimension normal to said scan path which is at least 100 mm and sufficient to implant ions over a full extent of said predetermined linear dimension of said workpieces on said supports.

A magnetic ion filter assembly for ion implantation apparatus comprising:

a flight tube defining an ion beam passage through said filter for desired ions, said beam passage having first and second cross-sectional dimensions extending respectively in first and second orthogonal directions, said first cross-sectional dimension being greater than said second cross-sectional dimension to accommodate a ribbon-shaped ion beam having major and minor cross-sectional dimensions and extending in a ribbon plane parallel to said first orthogonal direction;
and
a magnet assembly to provide a magnetic field extending in said second direction across said beam passage to deflect ions in a ribbon beam passing through said flight tube in said ribbon plane;
wherein said magnet assembly has first and second pairs of opposed magnetic pole pieces spaced apart along said ion beam passage and said pairs providing respective magnetic fields with a common polarity across said beam passage, each of said first and second pairs of opposed pole pieces having, with respect to an ion beam direction through said beam passage, a respective predetermined leading edge profile and a respective predetermined trailing edge profile.

1 more element

Dependencies are inferred from the claim text.

Ion implantation apparatus and a method

Life of this patent

Ion implantation apparatus and a method

Life of this patent

Abstract

Claims27