Oxidation is one major cause which degrades the reflectivity of the multilayer mirrors used for optics of EUV exposure tools. To estimate the change of reflectivity due to oxidation, modeling of the multilayer mirror oxidation was becoming greater importance. Bajt, et al experimentally evaluated the oxidation of the EUV multilayer mirrors with Ru cap using ALS at Lawrence Berkeley National Laboratory [1]. They compared the oxidation of EUV multilayer mirror cased by electron beam irradiation and EUV irraditation [2] Klebanoff, et al proposed the mitigation of oxidation by use of the ethanol [3]. Hollenshead and Klebanoff modeled EUV/H_2O oxidation of Ru coatings [4]. They detailed the oxidation of Ru coatings causing by H_2O. We have modeled the oxidation of the EUV multilayer mirror based on these prior studies. We have evaluated EUVL multilayer mirror oxidation model comparing its prediction with experimental data.
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