The silicon wafer is usually patterned with the mask set to make hundreds or thousands of the same IC. The circle below represents the wafer, the squares represent the copies of the maskset pattern exposed onto the wafer by the stepper. The light squares are completely within the wafer and thus may be functional chips, the others are only partial and so cannot be functional chips. Each of these ICs are then cut out of the wafer using a diamond edged saw and are called dies (or die, or dice).
