Synthesis of a Df-porous Si layer of mesostructure to develop the mechanisms of CO sensors

In this novel current work, double-face porous Si (Df-porous Si) was established via the double-beam laser-assisted etching (DB-LAE) technique, using two similar diode lasers, operating at 630 nm wavelength and 60 mW power. The work involved the development and study of Df-porous Si layer of Al/Psi/Si/Al with one-face, parallel, and series connections and Df-porous Si layer of Al/PSi/ Si/PSi/Al gas sensors under low concentrations (0.25–1 ppm) of CO gas molecules at room temperature. A significant improvement had been achieved in gas sensing characteristics involving current-frequency, sensitivity, stability, and temporal response in Df-porous Si with parallel connections when compared to the Df-porous Si sensors with one-face, and series connections . Low values (0.1, 0.06, and 0.19 ppm) of LOD for CO molecules in one face and Df-porous Si sensors at parallel and series connections were obtained, respectively. These improved characteristics were ascribed to the large sensing area and in parallel connections capacitance of the Df-porous Si layers.