提出基于连续元胞自动机的聚焦离子束溅射刻蚀工艺模型,该模型可以有效引入实际工艺参数和扫描策略,建立溅射与再沉积方程,准确地表达离子束加工导致的溅射和再沉积效应,精确地描述这些效应导致的表面结构演化过程。在多种工艺因素和扫描策略的条件下,工艺模型的计算结果中,溅射刻蚀与再沉积效应能够与试验现象一致。加工截面轮廓的模拟结果,刻蚀深度随时间变化相对误差小于8%,精度高于现有的模型,验证了模型的有效性。连续元胞自动机模型不仅具备计算精度高的特点,而且有更好的可视化输出效果,为聚焦离子束加工微纳结构提供工艺参数优化方法。
A new model based on the continuous cellular automaton (CCA) is introduced for the focused ion beam (FIB) etching process simulation. By considering the actual process parameters and the scan strategies, this method provides new sputtering and re-deposition functions to describe the effects, as well as the evolution of surface structures accurately. In various process conditions and scan strategies, the simulation results, compared with the experiments, show good performance in the reproduction of the sputtering and the re-deposition effects. And the cross-section profiles are successfully reproduced with etching depth relative error less than 8%, which validates this model. Compared with the reported simulation results, the proposed CCA model improves the simulation accuracy and the visual output, which provides a good solution in guiding the process parameter design and optimization for FIB micro-nanofabrication.
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