Method of manufacturing chips

A method of manufacturing chips by dividing a workpiece having a substrate harder than a monocrystalline silicon substrate along a grid of projected dicing lines, the method comprising:

• a cut groove forming step of, while holding the workpiece on a holding table such that a surface of the workpiece is exposed, cutting the workpiece along each of the projected dicing lines with a first cutting blade as it is vibrating at a frequency in an ultrasonic band, to form a cut groove in the workpiece such that the cut groove extends from the surface of the workpiece and terminates short of another surface of the workpiece that is positioned opposite the surface thereof;
• and
• a dividing step of, after the cut groove forming step, while holding the workpiece on the holding table such that the other surface of the workpiece is exposed, cutting off an uncut residual portion from the workpiece along each of the projected dicing lines with a second cutting blade different from the first cutting blade to divide the workpiece into a plurality of chips.