Morphology and Electrical Properties Nano Porous Silicon as a Sensor of CO۲ and N۲

We investigated the electrical behavior of Nano porous silicon layers in the presence of CO۲ and N۲ gases (at room temperature). A sample of p-type silicon wafer was poroused by electrochemical anodization in electrolyte which consist of DMF (dimethylformamide), HF acid and ethanol (C۲H۵OH). SEM spectra of Porous Silicon Nanostructure demonstrate the influence of various parameters such as anodization time, current density and electrolyte concentration has been investigated on pore formation. We also examine our test system for gas sensors. Electrical mechanisms of the sensors in room temperature are proposed. The results are shown that the Porous silicon layer is more sensitive to CO۲ than N۲ gas.

Keywords:

Porous silicon , DMF , Wafer , SEM