Extreme ultraviolet lithography (EUVL) is one of the most promising candidates for next generation lithography to achieve 22 nm technology node. It takes of extreme ultraviolet (EUV) at 13.5 nm. With this wavelength, all the exposure equipments must be reflective. Whereas, for the extreme ultraviolet irradiated optical elements, the two main mechanisms that reduce reflectivity of EUV reflective film are carbonization and oxidation of the film surface. Researching the mechanism of carbon deposited layer with surface molecule kinetic theory of EUV optical devices to find an effective way for inhibiting the deposition of pollution. We investigate the validity of models and assumptions by researching on carbon pollution layer model, indirectly proving the Boller′s theory “secondary electron induced decomposition is the main deposition process”. Present preliminary numerical results on the dependence of contamination rates on key parameters with the iterative method, and suggest a band of 50~80 nm where will produce a higher contamination rate.