厚胶光刻中光敏化合物浓度空间分布研究

厚胶光刻过程是一个复杂的非线性过程，其光刻胶内光敏化合物(PAC)浓度空间分布是影响显影面形的主要因素。根据厚层胶光刻的特点，结合光化学反应机理，利用角谱理论，分析了在曝光过程中光刻胶内衍射光场和PAC浓度的空间分布随时间的动态变化，以及后烘(PEB)过程对PAC浓度空间分布的影响。该方法数值计算结果准确，且速度快。数值模拟表明，其内部衍射光场分布与PAC浓度分布是一个动态的、非线性的相互影响过程；后烘工艺可平滑PAC浓度空间分布；PAC浓度空间分布是影响浮雕面形边沿陡度的一个重要因素。

Study on Distribution of PAC Concentration in Thick Film Resist

The lithography of thick film resist is a complex non-linear process. Dissolution rate of resist is mainly affected by distribution of PAC concentration in thick film resist. According to the lithographic characteristics of thick film photoresist,the diffractive field and distribution of PAC concentration are analyzed during exposure process, using principle of photochemistry reaction and angular spectrum theory. The impact of the post exposure baking process on PAC concentration distribution is also studied. This method has higher computation precision and less computation time, compared with previous methods. Numerical simulation results show that interactions between diffractive field and distribution of PAC concentration are dynamic and non-linear, the distribution of PAC concentration can be smoothed during post exposure baking process, and the side wall angle of the photoresist after development is greatly affected by the final distribution of PAC concentration.