| 摘要 |
PURPOSE:To prevent the surface contamination around a working part by irradiating laser light on the surface of a work object after forming a thin dielectric film thereon so that the material to be removed by melting the work object is splashed far off. CONSTITUTION:The laser light 1 is condensed by a condenser lens 2 and is projected on the working part 3 of a work piece 5 on a substrate 4 consisting of Si, glass, etc. A thin film material having such high mechanical strength as to hinder the removal of the work piece 5, for example, a pressure intensifying film 6 consisting of Si3N4 or SiO2 is preliminarily formed on the work piece and therefore, the process of melting, evaporating and splashing the material to be removed does not easily arise. The pressure intensifying film 6 is destructed at the point of the time when the mechanical strength of the pressure intensifying film 6 is exceeded. As a result, the melted and splashed material is splashed far off by the strong pressure and is cooled in the midway, by which the adhesive power to a peripheral member of the dropping material is decreased. The deposits to remain after cleaning are thus decreased and the residual contamination is lessened. |
