PURPOSE: To prolong the life of a dicing blade and to remove the occurrence of inferior products by a method in which while ultrasonic wave-vibration is applied in the feeding direction of the dicing blade, water is fed on a cutting surface, and a water film is formed and held on the blade surface in the working of a semiconductive wafer.

CONSTITUTION: A silicon wafer 3 is fixed onto a table 1 with an adhesive tape 2, and a dislike dicing blade 4 is moved in arrow direction with the rotation in arrow direction and cuts the wafer. Then, while water is fed on a cutting surface from the advancing direction of the dicing blade 4 by a nozzle 7, the table 1 is vibrated in the moving direction of the dicing blade 4 by an ultrasonic wave-vibrator 6. The frequency of this vibration is set e.g. at 20Hz so that a water film is formed on the surface of the dicing blade 4 and is held without scattering.