PURPOSE: To avoid that the surface of a thin film around a removal region is contaminated when a desired region in the film is removed by an irradiation operation with an energy beam by a method wherein the energy density of the energy beam is adjusted according to the absorption characteristic with reference to the energy beam of a contamination-preventing film.

CONSTITUTION: Before a laser beam 3 is irradiated, a contaminationpreventing film 1 is applied to the surface of a resist layer 2 on a support substrate 4 (a wafer). Then, when a removal region in the layer 2 is irradiated with the beam 3 from the upper part of the film 1, the energy density of the beam 3 is set to a minimum value which is sufficient to remove the layer 2 by an abrasion process when the absorption of the film 1 with reference to the beam 3 is small and does not satisfy a prescribed condition. Thereby, after the film 1 in the irradiated region has been removed, the film 1 in the circumference is not removed even when it is irradiated with a high-energy beam. As a result, the layer 2 is removed completely after it has been irradiated with a beam 6 whose energy density has been increased. Scattering substances 22 which are produced at this time are deposited on the film 1, and it is possible to avoid that the surface of the layer 2 is contaminated.