| 摘要 |
During the performance of a laser processing step of applying a laser beam to a wafer to form modified layers inside the wafer respectively along division lines, a predetermined one of the modified layers already formed is imaged by a camera from the back side of the wafer with predetermined timing, and a positional deviation of the predetermined modified layer from the corresponding division line is detected to calculate a correction value. Then, the correction value is added to data on applied position of the laser beam to thereby make the applied position of the laser beam coincide with each division line. Accordingly, a positional deviation of the modified layer to be formed after this correction from each division line can be suppressed. |
