| 摘要 |
<p>PROBLEM TO BE SOLVED: To efficiently remove foreign matters without causing damage of the surface. SOLUTION: In this apparatus, laser beams emitted from an excimer laser are s-polarized and are irradiated at an angleθof incidence of e.g. 5 deg. to the surface of a hard disc base sheet 12. Therefore, in comparison with a case of the angle of incidence of 90 deg., the area of irradiation to the hard disc base sheet 12 is increased and the laser density is decreased. In addition, as the laser beams reflected on the surface of the hard disc base sheet 12 are indirectly irradiated to a foreign matter 44, irradiation dose is increased. In addition, as electric vector of the s-polarized laser beams is oscillated in the parallel direction to the surface of the hard disc base sheet 12, this oscillation energy effectively acts as a force for eliminating the foreign matter 44.</p> |
