用于0.35μm接触孔图形相移掩模研究

Phase Shifting Mask for 0.35 μm Contact Holes

基于霍普金斯 (Hopkins)理论 ,通过计算 0 .35μm方孔的传统透射掩模、边缘相移掩模、部分边缘相移掩模、辅助相移掩模以及衰减相移掩模在硅片表面空间像的光强分布 ,找出了适合于各种相移掩模的最佳参数。其中衰减相移掩模对提高光刻分辨率和增加焦深最为明显 ,尤其在相干因子 (σ)较小时更是如此。

Aerial image distribution of a 0.35 μm contact hole with traditional mask, rim phase shifting mask (PSM), partial rim PSM, attenuating PSM are calculated based on Hopkins model, and the optimum parameters of different PSM are obtained. Attenuated PSM in enhancing resolution and improving the depth of focus in photolithography is of the most effective among them, especially when partial coherent factor (σ) is small.