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As the width of the line decreases, there are advantages such as improved performance, reduced unit price, and reduced power consumption, but high accuracy is required. Heat deformation by exposure light is one of several factors that reduces accuracy. These variations cause overlay and focus problems and can sometimes lead to serious overlay and CD variation. Because the linewidth is reduced to x nm, the overlay error of several nm and the critical dimension (CD) value are also greatly affected. Currently, it can be solved to some extent by stage adjustment and fine-tuning, but the problem still remains. In this paper, we checked the mechanism of wafer deformation due to energy absorption during exposure, changing the conditions of pattern linewidth and line and space (L/S).
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