MELTING AND VAPORIZATION FOR LARGE-AREA FILM REMOVAL WITH A CHEMICAL OXYGEN-IODINE LASER

Large-area film removal with lasers is a physical process of melting a nd vaporization of films. A mathematical model is developed to simulat e the melting and vaporization of films under the irradiation of a che mical oxygen-iodine laser. The cross section of the film after laser s canning and the substrate surface temperature during laser irradiation are presented. There is an optimum laser power at which relatively wi de films can be removed by maintaining low temperature at the substrat e surface. The optimum laser power is associated with other process pa rameters. The results of film removal with TEM31 and TEM00 beams are c ompared, and the laser mode with more uniform intensity distribution i s found to be more effective for large-area film removal. (C) 1997 Ame rican Institute of Physics.