US Patent 7285788 Ion beam extractor

An ion beam extractor controls a direction and an intensity of ion beams by adjusting a voltage applied to a grid having slits formed therein, thereby enhancing uniformity of an etching rate of a wafer, leading to an increase of productivity of semiconductor diodes. The ion beam extractor comprises an ion source to produce an ion beam and at least one grid located at a rear end of the ion source in a progressing path of the ion beam produced by the ion source to adjust a direction of the ion beam by controlling a voltage applied to the at least one grid.