硅含量对SiO_x薄膜光学和电学性能的影响

Effects of Si Content on the Optical and Electrical Properties of SiO_x Films

利用射频磁控溅射法通过调节硅(Si)靶的溅射功率制备了不同的富硅氧化硅(SiOx,1<x<2)薄膜。通过高温热处理,得到了镶嵌在SiOx薄膜中的硅纳米晶(Si-NCs)。而SiOx薄膜热处理后的光致发光(PL)强度及其MOS器件的导电性都存在随其硅含量的增大而先增强后减弱的趋势,且光致发光有一定的红移现象。这是由于随着硅含量的增大,SiOx薄膜中Si-NCs的结构与分布发生改变,形成"接触"Si-NCs,从而使得光学和电学性能发生改变。

Silicon-rich silicon oxide （SiOx, l〈x〈2） films were deposited by RF magnetron sputtering through adjusting the sputtering power on silicon （Si） target. After high temperature annealing, Si nanocrystals （Si-NCs） embedded in Si-oxide matrix were formed through phase separation. With the increase of Si content, the photoluminescence （PL） intensity of Si-NCs and the conductivity of MOS devices of the annealed SiOx films first increase and then decrease. Meanwhile, there is a red shift of PL peak. These phenomenons are due to, with the increase of Si content, the variation of the structure and distribution of Si- NCs and the formation of ＂touching＂ Si-NCs.