| 摘要 |
A laser processing method for preventing particles from occurring from cut sections of chips obtained by cutting a silicon wafer is provided. An irradiation condition of laser light L for forming modified regions 7 7 to 7 12 is made different from an irradiation condition of laser light L for forming the modified regions 7 13 to 7 19 such as to correct the spherical aberration of laser light L in areas where the depth from the front face 3 of a silicon wafer 11 is 335 µm to 525 µm. Therefore, even when the silicon wafer 11 and a functional device layer 16 are cut into semiconductor chips from modified regions 7 1 to 7 19 acting as a cutting start point, twist hackles do not appear remarkably in the areas where the depth is 335 µm to 525 µm, whereby particles are hard to occur. |
