多层多孔硅的SPM研究

SPM research on multilayer porous silicon

多层多孔硅是采用交替变化脉冲腐蚀电流密度的方法制成的多孔度周期性变化的多孔硅结构，我们用ＡＦＭ对多层多孔硅结构的侧向解理的截面进行观测，得到了不同多孔度层及其界面处的图像。发现不同周期中相同条件下腐蚀得到的多孔硅层，其层厚随周期的不同而不同，从而限制了多孔硅发光峰半宽的缩小。对多层多孔硅的电化学腐蚀机理作了初步的探讨。

Multilayer porous silicon(MLPS) was etched with alternate varied current density which made the porosity change periodically.We use AFM to investigate the cross section of the MLPS structure and get images of different layers with different porosity.It is found that there is a inhomogenity of thickness of different layers in different period which was etched under the same condition.This inhomogenity lead to the broadening of the luminescent peak of the MLPS.