The printability of an extreme ultraviolet lithography (EUVL) contact layer defect mask was studied using numerical analyses. Three-dimensional models using rigorous electromagnetic simulations were used to predict the mask printing process at the 30 nm technology node. Two types of EUVL mask contact layer defects were studied, i.e., absorber and buffer layer defects. For the absorber, corner and center defects were evaluated and compared for different contact sizes. For the buffer layer, corner defects were investigated for three different materials: ruthenium, carbon, and silicon oxide. It was found that center contact defects were worse than corner defects. For buffer layer defects, the study showed that for a given size, ruthenium defects have the worst effect, followed by carbon and silicon oxide.