Approach to contacting nanowire arrays using nanoparticles

US8324703B2 · kind B2 · utility

Assignees

• University of Maryland · US
• Government of the United States of America, as represented by the Secretary of Commerce · US

Inventors

• Prahalad Parthangal · Gaithersburg, US
• Michael R. Zachariah · Potomac, US
• Richard E. Cavicchi · Washington Grove, US

Key dates

• Filing date: Apr 29, 2008
• Grant date: Dec 4, 2012
• Expiry date: Nov 21, 2029

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N27/414
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An in situ approach toward connecting and electrically contacting vertically aligned nanowire arrays using conductive nanoparticles is provided. The utility of the approach is demonstrated by development of a gas sensing device employing the nanowire assembly. Well-aligned, single-crystalline zinc oxide nanowires were grown through a direct thermal evaporation process at 550° C. on gold catalyst layers. Electrical contact to the top of the nanowire array was established by creating a contiguous nanoparticle film through electrostatic attachment of conductive gold nanoparticles exclusively onto the tips of nanowires. A gas sensing device was constructed using such an arrangement and the nanowire assembly was found to be sensitive to both reducing (methanol) and oxidizing (nitrous oxides) gases. This assembly approach is amenable to any nanowire array for which a top contact electrode is needed.