Photomasks for the semiconductor chip production are typically written with either laser- or e-beam writers. Laser tools have the advantage of fast writing speeds and are overall more cost effective than e-beam writers. On the other hand, ebeam writers achieve significantly better mask accuracy in terms of minimum Critical Dimension (CD) and CD uniformity. Despite the accuracy disadvantage of laser writers, on average, they account for approximately 70% of all masks delivered by the mask industry, during the years between 2018 and 2020. The widespread use of laser writers and their technical limitations make them excellent candidates for Mask Process Corrections (MPC). This work investigates the feasibility of using MPC, developed for e-beam writers, with minor modifications to laser writers. It will be shown that adding an anisotropic component to the models used for e-beam lithography is sufficient for simulating the laser tool signature. With such models, MPC provides an opportunity to expand the application space of laser tools into CD ranges, not possible without MPC and enables tool signature matching between mask writers similar to that used for e-beam writers.
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