改进的多孔硅生长模型和计算机模拟

A Modified Model and Computer Simulation for Porous Silicon Formation

基于多孔硅生长过程中阳极化电流,氢氟酸(HF)含量与多孔硅微结构的关系,提出一个改进的多孔硅生长模型,并进行了计算机模拟.该模型吸收了限制扩散模型的优点,同时考虑了F-与空穴的反应过程因素,利用该模型可以模拟出多孔硅形成过程中大电流条件下的电化学抛光现象.二维(100×100)点阵模拟结果与实验数据具有较好的匹配性,模拟得出的多孔硅的多孔度同实验数据相比较,误差不超过10%.

A modified model for porous silicon formation is proposed and computer simulation has been carried out based on the dependence of the porous silicon microstructure on anodic current and HF concentration during porous silicon formation. The model not only takes the advantage of diffusionlimited model,but also considers reactions between F- ions and cavities. By using the modified model,the electrochemical polishing phenomenon of silicon with large anodic current during PS formation canbe simulated. The results of two dimensional (100×100) lattice simulation show a good match with experimental data. The deviation of the simulation results of PS porosity is less than 10 percent from the experimental data.