用电化学方法制备多孔硅

Preparation of Porous Silicon by Electrochemical Method

为了深入了解多孔硅的特性,用电化学方法在双槽电解池中腐蚀形成了不同结构形貌的多孔硅层.结果发现,在本试验控制条件下,p+掺杂的硅比n+的容易腐蚀,而且孔的分布也比较均匀.轮廓仪的分析表明,电化学方法形成的多孔硅表面和内部结构比较规则,而且深度比较大,可在MEMS技术中得到广泛应用.对试验中出现的龟裂现象进行了分析,认为这是由于孔内液体挥发产生的毛细应力多孔硅氧化过程中因晶格膨胀和易位形成的应力联合作用的结果.

By using the electrochemical method,porous silicon of different structures and morphologies was prepared in double cell,in order to revealits features. The results have shown that the p^+ silicon can be corroded more easily than n^+ silicon, and the distribution of the pores on p^+ silicon is more uniform. Its surface and inner structure are also very uniform,and a deep porous silicon layer can be reached easily. It can be used in MEMS technology widely. The cracking phenomenon occurred in the experiments was also studied.It is thought to be the acting of the stresses created by the volatilizing of the solutions in the pores and the expanding and shifting of the crystal lattice in the process of porous silicon oxidization.