用高分辨电子能量损失谱和紫外光电子谱研究多孔硅的电子结构

Electronic Structure of Porous Silicon Studied by HREELS and UPS

本文首次使用分辨电子能量损失谱（ＨＲＥＥＬＳ）和紫外光电子能谱（ＵＰＳ）研究新腐蚀的多孔硅样品（ＰＳ）的电子结构．实验结果发现，从ＨＲＥＥＬＳ谱中能量损失阈值测得的多孔硅的能隙最可几值移到２．９ｅＶ左右，与文献报道的光激发谱（ＰＬＥ）的结果相近．ＵＰＳ结果发现多孔硅费米能级到价带顶的距离不同于单晶硅，结合ＨＲＥＥＬＳ和ＵＰＳ结果可以初步得出多孔硅与硅界面的能带排列．

Abstract High resolution electron energy loss spectroscopy (HREELS) and ultraviolet photoelectron spectroscopy (UPS) are utilized to study the electronic structure of newly etched porous silicon for the first time. The results show that the energy loss threshold corresponding to the probable energy gap of porous silicon shifts to 2. 9 eV, consistent with that reported by PLE results. UPS results show that the difference between Fermi level and the valence band maxium in porous silicon is different from that in crystalline silicon. By combining the HREELS and UPS results,the band lineup at the porous silicon/crystalline silicon interface is presented.