ALIGNMENT OF METAL-OXIDE NANOTUBES AND NANOWIRES FOR CHEMICAL MICRO SENSORS

Casey S. Mungle, Kurt D. Benkstein and Steve Semancik

While metal oxide nanostructures have shown potential as highly sensitive chemical detectors due to their inherent material properties and structural scale, incorporating the materials in MEMS sensing devices has proven challenging.  Novel methods have been employed to deposit and align nanotubes and nanowires on micro-hotplate devices utilizing both new magnetic alignment and microscale dielectrophoresis techniques for the purpose of constructing chemical sensors.  One dimensional nanostructures are fabricated using template-assisted methods, and then dispersed in solution.  TiO2 nanotubes are produced via sol-gel methods, and Ni nanowires are electrodeposited inside the nanotubes, before dissolution of the template, to provide a ferromagnetic core for magnetic manipulation.  The magnetic core is a sacrificial layer used for assembling ordered arrays of nanotubes under application of externally applied fields.  Tin metal nanowires are produced via electrodeposition in similar polycarbonate templates and converted into SnOx with a thermal-oxidation step after deposition and alignment.  These alignment techniques enable the fabrication of model assemblies that will be used to investigate how the scale and orientation of nanotube arrays affects their sensing characteristics and develop methodology to fabricate improved chemical sensors.  Preliminary sensing results are shown to demonstrate the performance of metal oxide nanowires. 

 

Casey S. Mungle

Mentor: Steve Semancik

Process Measurements Division (836)

CSTL

A303, Bldg. 221

MS 8362

Office: 301-975-5153

Fax: 301-975-2643

casey.mungle@nist.gov

Sigma Xi: No

Category: Materials, Engineering