Haimi E, Lindroos V K, Nowak R
Laboratory of Physical Metallurgy and Materials Science, Helsinki University of Technology, P.O. Box 6200, 02015 HUT, Finland.
J Nanosci Nanotechnol. 2001 Jun;1(2):201-6. doi: 10.1166/jnn.2001.021.
The present work addresses the formation of porous silicon layers by means of anodic dissolution of p- and p(+)-type boron-doped (100) silicon wafers in 15, 25, and 35 vol% HF-ethanol solutions. The study concerned the dependence of the porous silicon layer growth rate dh/dt on electric current density i as well as on HF concentration. The formation of a porous silicon layer was found to follow a generic linear relationship, in(dh/dt)--in(i), which holds irrespective of the processing conditions. The combination of two equations, experimental and theoretical, derived from Faraday's equation, allowed us to reach conclusions on the relationship between the growth rate dh/dt and the degree of porosity, constituting a first step in prediction of the nanoporous structure of silicon based on processing parameters. This electrochemical approach complements physical models of silicon pore formation.
本工作研究了通过在体积分数为15%、25%和35%的氢氟酸 - 乙醇溶液中对p型和p(+)型硼掺杂(100)硅片进行阳极溶解来形成多孔硅层。该研究关注多孔硅层生长速率dh/dt与电流密度i以及氢氟酸浓度之间的关系。发现多孔硅层的形成遵循一般的线性关系，即ln(dh/dt) - ln(i)，这与加工条件无关。结合从法拉第方程推导得出的两个方程（实验方程和理论方程），使我们能够得出关于生长速率dh/dt与孔隙率之间关系的结论，这是基于加工参数预测硅纳米多孔结构的第一步。这种电化学方法补充了硅孔隙形成的物理模型。
