| dc.description.abstract | In this study, the high aspect ratio, large-area, vertically-aligned single crystalline silicon
nanowire arrays (SiNWs) on P type (001) and N type (001) silicon substrate is successfully fabricated by the two-step metal-catalyzed electroless etching approach. It is proved the variation trend and mechanism by the acetone and oxygen. In addition, the single crystalline porous silicon nanowire arrays is further fabricated by the lateral etching, the porous nanostructure exhibited excellent specific surface area, from the result of gas sensing, it substantially enhance performance for acetone, and then we use the best one is uniformly decorated Ag on the porous SiNWs by the electroless Ag deposition. The produced porous Ag/SiNWs Schottky junction gas sensor is able to operate at any voltage and exhibit response, sensitivity, response time and recovery time.
The flexible porous Ag/SiNWs Schottky junction gas sensor is demonstrated by combining with ultra-thin Si substrate which has excellent bending ability, and it can be applied to achieve gas sensing on 2.5 cm and 1.6 cm curvature surface. The resulting response enhancement can be attributed to specific surface area enhancement after bending.
In the last, we proposed improvement for the increase of recovery time caused by porosity. The front side is based on nanowires and the back side is based on holes. There is another way to desorb. Therefore, we look forward to shortening the recovery time and optimizing the performance of the device. | en_US |