Apparatus for rejecting failure crystal grains in chip spot measurement process

The utility model provides an apparatus for rejecting failure crystal grains in a chip spot measurement process. According to the apparatus, when chip crystal grains of a wafer are tested, in case that unqualified failure crystal grains are discovered, normal dotting is carried out on the failure crystal grains, magnetic printing ink is injected, two nonmagnetic guide rails are arranged at the two sides of each crystal grain which is cut and separate, the height between the guide rails and the separate crystal grains is 4 to 6mm, a magnetic steel roller is erected between the two guide rails, and the magnetic steel roller is driven by a motor to roll back and forth along the guide rails so as to absorb the failure crystal grains on the wafer. The magnetic polarity of the magnetic printing ink is opposite to the magnetic polarity of the magnetic roller. The apparatus provided by the utility model has the advantages of being high in rejection rate of the unqualified crystal grains and high in yield rate and greatly reducing the production cost.