Large area, dense silicon nanowire array chemical sensors

Abstract

The authors present a simple top-down approach based on nanoimprint lithography to create dense arrays of silicon nanowires over large areas. Metallic contacts to the nanowires and a bottom gate allow the operation of the array as a field-effect transistor with very large on/off ratios. When exposed to ammonia gas or cyclohexane solutions containing nitrobenzene or phenol, the threshold voltage of the field-effect transistor is shifted, a signature of charge transfer between the analytes and the nanowires. The threshold voltage shift is proportional to the Hammett parameter and the concentration of the nitrobenzene and phenol analytes.

A Perspective on Nanowire Photodetectors: Current Status, Future Challenges, and Opportunities

“…Over the last ten years or more, parallel developments and advances in the "bottom-up" synthesis of 1-dimensional NWs (1-D-NWs) with precise control on the chemical compositions, morphologies, and sizes have enabled researchers to fabricate novel nanodevices, such as NW FETs (NWFETs) [10]- [13], LEDs [14], [15], complimentary inverters [16], complex logic gates [17], lasers [18], chemical sensors [19]- [21], and PDs [22]. Simultaneously, the current state-of-the-art silicon CMOS technology has already been scaled down to nanometer feature sizes and is approaching the physical lower limit of beneficial scaling.…”

Effect of nanoscale patterned interfacial roughness on interfacial toughness.

“…53 The patterns were created using a Nanonex 2000 NIL and two silicon grating molds fabricated using laser interference lithography. One mold was a 500 nm dense pitch 250 nm line/space the other a 200 nm dense pitch 100 nm line/space.…”

Controlled Synthesis of Horizontal Silicon Nanowires for Biosensor Application

“…[1][2][3] Functionalized with biomaterials, SiNWs connected between electrodes operate well in sensing devices. 4 The top-down method is considered the representative approach for the synthesis of SiNW arrays, and is based on the microelectromechanical systems (MEMS) process, which has been broadly applied with good controllability of diameter and length because of the lithography process.…”