用于快速光学邻近校正的可变阈值光刻胶模型

Variable threshold resist models for fast OPC

提出了用于光刻仿真的建模流程.用高斯滤波器与空间影像进行卷积,得到改进的空间影像来模拟光刻胶的扩散,然后使用可变阈值光刻胶模型,以实际工艺数据拟合该模型参数,再把改进空间影像的相关信息作为输入,并根据可变阈值光刻胶模型所确定的光强阈值来预测CD(criticaldimension)变化,从而使光刻仿真的结果更精确地附合实际测量数据.由于正确地表征了实际工艺的特性,模拟结果显示,多参数光刻胶模型更适于实际开发的光学邻近校正(opticalproximitycorrection,OPC)仿真工具.

The modeling flow for lithography simulation is presented in this paper. A modified aerial image was obtained by convolving the aerial image with a Gaussian filter to smear the image in a manner analogous to resistive diffusion, and then applying a variable threshold resist model on the modified image to predict the CD (critical dimension) variations. The related information on the modified aerial image overe were taken as input parameters for the model, while the real manufactured CDs on wafer were taken as the model fitting target. As the multiparameter resist model properly characterizes real processes,simulation results have shown that this model is suitable to be used in practical OPC simulation tools.