纳米多孔硅可控制备研究

Study on controllable preparation of nanometer porous silicon

采用了自制双槽和电化学腐蚀法在不同电阻率的硅片上制备出表面平整度很好的纳米多孔硅层,利用场发射扫描电子显微镜对多孔硅的微观形貌进行了分析表征。实验表明多孔硅的孔径、孔隙率和厚度随电化学腐蚀的电流密度和腐蚀时间增加而增加,且电解液中HF（40%）和无水乙醇（99.7%）的配比很趋近时,多孔硅的孔洞分布均匀性越好。在电阻率为0.01~0.02Ω·cm的P型硅片上制备的纳米多孔硅其效果相比其他电阻率的要好。

The nanometer porous silicon（ PS） of great surface roughness was fabricated by electrochemical etching method used the home-made double-tank setup with various resistivity silicon. The micro-structure of PS was characterized with field emission scanning electron microscope（ FESEM）. The experiment results show that the pore diameter,porosity and thickness of the PS are increased with increasing of the current density and corrosion time of the electrochemical etching. While the electrolyte ratio of HF（ 40%） and absolute ethyl alcohol（ 99. 7%） is approached,the pore distribution uniformity of PS is better. The preparation effectiveness of nanometer PS is formed on P ~ type 0. 01 ~ 0. 02 Ω cm silicon substrate is better than others.