多孔硅阵列结构的形貌研究

Study on morphology of silicon macropore array

采用电化学腐蚀方法分别在HF+异丙醇(IPA)和HF+IPA+十六烷基三甲基氯化铵(CATC)溶液中制备多孔硅结构阵列,分别讨论HF酸浓度、CTAC、刻蚀电流、刻蚀时间对多孔硅阵列的形貌的影响。结果表明:在质量分数40%HF,H2O,IPA的体积比为7∶4∶29时得到优化的多孔硅阵列;腐蚀电流密度越大,孔壁越薄;初始的腐蚀会向外扩展直到形成的孔径达近10μm,在窗口8μm、间距5μm的硅片上腐蚀的孔壁表面出现小孔。CTAC的加入会使孔壁上刻蚀出小孔,并随着CTAC的增加,小孔的孔径减小,数量增加。

Silicon macropore arrays were prepared by electrochemical etching in the solution of HF＋IPA（isopropanol） and HF＋IPA＋CATC（cetyltrimethylammonium chloride）.The effects of HF concentration,CTAC,etching current,etching time on the array morphologies were discussed.The optimized macropore array was obtained when the volume ratio of 40%HF,H2O,IPA is 7∶4∶29.The pore wall is decreased with increasing the etching current and the initial etching expands in the direction of pore diameter until the pore diameter of about 10 μm.Regular arrays are not formed on the silicon with etching windows of 8 μm and spacing of 5 μm.Small pores are formed on macropore walls when CTAC is added in the solution.The small pores become smaller and the number of them is increased with increasing CTAC.