Real-time Intelligent Chemical and Biological Nanosensors on Flexible Platform - II

摘要

In this report, we investigate the current rectification property of chemical vapor deposited (CVD), as-grown single-walled carbon nanotubes (SWNTs). We use the long strands of SWNT bundles to fabricate multiple arrays of switching devices with channel lengths of 3, 5, 7, and 10 micrometer on a 15 x 15 mm2 silicon dioxide (SiO2) on silicon (Si) substrate. A majority of the fabricated devices, regardless of channel length, showed current rectification characteristics with high throughput of current (I) in the forward bias (V). Atomic force microscopic (AFM) analysis of the device structure and surface topology of SWNTs suggests the observed rectification of current results from surface irregularities and is possibly due to change in the chirality of a single tube. Using fabricated SWNT field-effect transistors (FETs), we have demonstrated the effects of gases, particularly O2and N2, on the fabricated devices.