低温下多孔硅电学性质研究

Study of electrical properties of porous silicon at low temperature

在低温下 ( 1 0～ 30 0K)对多孔硅 (Al/多孔硅 /单晶硅结构 )的I U特性进行了测量 ,得到了I U特性随温度的变化曲线 .结果表明 ,低温下多孔硅的电阻率远大于单晶硅 ,当温度变化时 ,电阻率的变化不是单调的 .其原因一是电流的主要输运机制随温度的降低发生变化 ;二是多孔硅中的缺陷态俘获载流子的能力随温度降低而变弱 .

The I U characteristics of porous silicon (structure: Al/PS/Si) is measured at low temperature (10～300 K). The temperature dependence of I U characteristics is obtained. The results show the electrical properties are different between porous silicon and Silicon at low temperature. The resistivity of porous silicon is much bigger than silicon and the resistivity varying with temperature is not monotonic. One reason is the mechanism of current transport is varying with temperature; the other is the ability of defect catching carriers is decreased when the temperature decreased.