US Patent 8044374 Ion implantation apparatus

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 the wheel is formed with tensioned spokes supporting a rim carrying the wafer supports. The spokes may be used for carrying cooling fluid to and from the wafer supports. In one embodiment, 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.