US Patent 7568489 Method of and apparatus for eluting impurities

Impurities can be eluted simultaneously from a plurality of local areas of a surface layer of a semiconductor substrate. A supporting unit supports the substrate, and a sample plate is disposed on the surface of the substrate. The sample plate has a plurality of holes that expose the local areas of the surface of the substrate. Eluant is provided onto the local areas of the surface layer of the substrate through the holes in the sample plate. The impurities are thus dissolved by the eluant to produce a sample. A nozzle transfers the sample from the local areas of the surface of the substrate to a plurality of sample cups. Therefore, samples from the surface layer of the substrate may be produced in a short amount of time.