Large-area film removal with lasers is a physical process of melting and vaporization of films. A mathematical model is developed to simulate the melting and vaporization of films under the irradiation of a chemical oxygen–iodine laser. The cross section of the film after laser scanning and the substrate surface temperature during laser irradiation are presented. There is an optimum laser power at which relatively wide films can be removed by maintaining low temperature at the substrate surface. The optimum laser power is associated with other process parameters. The results of film removal withTEM31andTEM00beams are compared, and the laser mode with more uniform intensity distribution is found to be more effective for large-area film removal. ©1997 American Institute of Physics.