Patent ID: 7294438

Claim:
A method of producing a reflective mask comprising a substrate, a reflective multilayer film formed on the substrate to reflect exposure light, and at least one layer formed as a patterned layer on the reflective multilayer film to define a nonreflecting region for the exposure light, the method comprising the steps of: (a) patterning a layer formed on and adjacent to a topmost layer of the reflective multilayer film; and (b) removing a reaction product produced following patterning in the step (a) and deposited on an exposed surface of the reflective multilayer film which is exposed as a result of patterning in the step (a) wherein: the patterned layer defining the nonreflecting region for the exposure light comprises a laminated film including an absorber layer for absorbing the exposure light and a buffer layer made of a material resistant against an environment upon patterning of the absorber layer; the laminated film being formed on and adjacent to the topmost layer of the reflective multilayer film, the layer patterned in the step (a) being the buffer layer.