Si衬底表面圆柱形抗反射周期微结构的设计及制作

Design and manufacture of columned antireflective periodic microstructures on the surface of Si substrate

应用严格耦合波分析方法(RCWA),在本征硅片衬底表面设计并制作了一种圆柱形抗反射微结构元件。通过MATLAB软件模拟仿真确定其最优参数组合,使反射率设计值为3%。应用二元曝光技术和反应离子刻蚀技术制作了单面和双面的圆柱形微结构,根据结果得到射频功率、气体流量及工作气压对微结构侧壁陡直度及形貌具有很大影响。还分析比较了形状(t为实际柱顶面直径与底面直径之比)与反射率的关系。采用热场发射扫描电子显微镜对该结构进行形貌表征,综合显微成像红外光谱仪对反射率进行测量。实验结果:制作了单面、双面微结构与无结构本征硅片反射率做比较双面圆柱形微结构的抗反射效果最好,反射率达8%左右,基本达到抗反射设计要求。

Based on the rigorous couple-wave analysis （RCWA） method, columned antireflective microstructure on surface of Si substrate though the MATLAB software was optimized and antireflective effect combination structure parameters were obtained, and periodic two-dimensional array of cylindrical micro-structure expression was deduced, so that the reflectance of the design value was 3%. The single and double microstructure were fabricated by reactive ion etching and binary exposure technology, and its surface topography was analyzed by thermal field emission scanning electron microscopy（SEM）, combined with infrared imaging spectrometer for measurement and analysis of its production structure. The results reveal that the reactive gas flow rate, Radio Frequency （RF） power and chamber pressure are critical for the morphology of the microstructure and the steepness of sidewall. The effect of profile shape of the anti-reflective properties in actual manufacturing process was discussed, and its surface topography was analyzed by thermal field emission scanning electron microscopy （JSM-7800F）, combined with infrared imaging spectrometer （Spotlight 400） for measurement and analysis of its production structure. The experimental results illustrate that the double-sided columned microstructure can have excellent average anti-reflective rate preferably about 8%. Basic design reaches the design requirements.