University of California

Toyota Motor Engineering & Manufacturing North America, Inc.

Joshua Goldberger

Peidong Yang

Rong Fan

Arun Majumdar

Rongrui He

Deyu Li

Yiying Wu

Minjuan Zhang

Allon I Hochbaum

Melissa Fardy

Oded Rabin

Yi-Ying Wu

Fluidic nanotube devices are described in which a hydrophilic, non-carbon nanotube, has its ends fluidly coupled to reservoirs. Source and drain contacts are connected to opposing ends of the nanotube, or within each reservoir near the opening of the nanotube. The passage of molecular species can be sensed by measuring current flow (source-drain, ionic, or combination). The tube interior can be functionalized by joining binding molecules so that different molecular species can be sensed by detecting current changes. The nanotube may be a semiconductor, wherein a tubular transistor is formed. A gate electrode can be attached between source and drain to control current flow and ionic flow. By way of example an electrophoretic array embodiment is described, integrating MEMs switches. A variety of applications are described, such as: nanopores, nanocapillary devices, nanoelectrophoretic, DNA sequence detectors, immunosensors, thermoelectric devices, photonic devices, nanoscale fluidic bioseparators, imaging devices, and so forth.

Fluidic nanotubes and devices

A method for the non-catalytic growth of nanowires is provided. The method includes a reaction chamber with the chamber having an inlet end, an exit end and capable of being heated to an elevated temperature. A carrier gas with a flow rate is allowed to enter the reaction chamber through the inlet end and exit the chamber through the exit end. Upon passing through the chamber the carrier gas comes into contact with a precursor which is heated within the reaction chamber. A collection substrate placed downstream from the precursor allows for the formation and growth of nanowires thereon without the use of a catalyst. A second embodiment of the present invention is comprised of a reaction chamber, a carrier gas, a precursor target, a laser beam and a collection substrate. The carrier gas with a flow rate and a gas pressure is allowed to enter the reaction chamber through an inlet end and exit the reaction chamber through the exit end. The laser beam is focused on the precursor target which affords for the evaporation of the precursor material and subsequent formation and growth of nanowires on the collection substrate.

Method of non-catalytic formation and growth of nanowires

Methods of fabricating uniform nanotubes are described in which nanotubes were synthesized as sheaths over nanowire templates, such as using a chemical vapor deposition process. For example, single-crystalline zinc oxide (ZnO) nanowires are utilized as templates over which gallium nitride (GaN) is epitaxially grown. The ZnO templates are then removed, such as by thermal reduction and evaporation. The completed single-crystalline GaN nanotubes preferably have inner diameters ranging from 30 nm to 200 nm, and wall thicknesses between 5 and 50 nm. Transmission electron microscopy studies show that the resultant nanotubes are single-crystalline with a wurtzite structure, and are oriented along the &#x3c;001&#x3e; direction. The present invention exemplifies single-crystalline nanotubes of materials with a non-layered crystal structure. Similar 'epitaxial-casting' approaches could be used to produce arrays and single-crystalline nanotubes of other solid materials and semiconductors. Furthermore, the fabrication of multi-sheath nanotubes are described as well as nanotubes having multiple longitudinal segments.

Sacrificial template method of fabricating a nanotube

Growing community of inventors

Berkeley, CA, United States of America

Joshua Goldberger