Enabling source and mask optimization by a dynamic aberration imaging model across the full exposure field

The current SMO method has been employed to improve lithography performance at a point in the Field of View (FOV) without considering the influence of aberrations varies with the relative motion between the wafer and the FOV during exposure (dynamic aberration). Otherwise, the non-uniformity of the image quality in the vertical scanning direction is also ignored which cannot meet the performance at full exposure field. A Source and Mask Optimization (SMO) method is proposed via a dynamic aberration imaging model to compensate for that influence. According to the characteristics of the Deep Ultraviolet Lithography (DUVL) pulse laser, the model performs a weighted summation of the area images at different positions along the scanning path. The cost function is designed to have a weighted sum of representative scanning paths to balance the FOV imaging quality. Compared to the current SMO method, the proposed method effectively reduces pattern error (PAE) and improves average imaging performance across the full field.