Patent ID: 7029808

Claim:
A process for exposing a substrate in an exposure apparatus, which comprises the steps of: providing a substrate coated with the radiation-sensitive coating material comprising: a base polymer; a solvent; a radiation-active substance forming an acid upon irradiation with energetic radiation; and a fluorescent substance having a fluorescence property, said fluorescent substance changing a fluorescence in dependence on an acid fraction present in a material surrounding said fluorescent substance; loading the substrate into an exposure apparatus having at least one first sensor for detecting light re-emitted by the fluorescent substance in the coating material within a first wavelength range; starting a first exposure operation by projecting a pattern into the photosensitive layer; firstly measuring a first intensity of light emitted by the fluorescent substance at a first point in time with the at least one first sensor; at least once secondly measuring a second intensity of light emitted by the fluorescent substance at at least one second point in time, with the at least one first sensor; comparing the first intensity with the second intensity; and ending the exposure operation in dependence on a comparison result of the comparing step.