电子散射参数提取的新方法

准确提取电子散射参数是确保纳米级电子束光刻邻近效应校正精度的关键。采用了一种不基于线宽测量和非线性曲线拟合的电子散射参数提取的方法。邻近效应校正的近似函数采用双高斯分布,其中η的提取是基于设计线宽变化与相应曝光剂量之间的线性关系进行拟合而得;α和β的提取则是分别根据前散射和背散射的范围设计特定的提取版图,并根据电子束邻近效应产生的特殊现象进行参数值的确定。根据此方法提取了150nm厚负性HSQ抗蚀剂层在50kV入射电压下的散射参数,并将其应用于邻近效应校正曝光实验中,很好地克服了电子束邻近效应的影响,验证了此方法提取电子束曝光邻近效应校正参数的实用性及准确性。

Novel Method of Electron Scattering Parameters Determination

Getting the proximity effect parameters exactly is the key of proximity effect correction in the electron beam lithography especially when the machining dimension goes deep into 100 nm.A novel method of the electron scattering parameters determination was proposed,which is independent of linewidth measurement and nonlinear curve fitting.Double Gaussian distributing was used as the proximity function.η was decided by linear fitting according to the relation between the linewidth change and dose.α and β were decided by the special layouts and characteristics in proximity effect correction.According to the methods mentioned above,the electron scattering parameters on 50 kV of 150 nm-thickness HSQ resists were extracted,and the better results in the actual proximity effect correction were obtained.The result validates the practicability and veracity of this method.