• The lab-demonstrated potential of nanomaterials is restrained by the difficulty of producing them in quantity. Two new techniques could bring nanomaterial mass production to fruition within one and five years, respectively.
• Very stable, durable, lightweight, and transparent magnets with major potential impacts on lasers and holography are under development.

Nanodevices Easier to Make

A simple new method to grow silicon nanowires and carbon nanotubes directly on microelectronic components could mean not only inexpensive micro-miniature sensors (such as the “dust motes” mentioned in the Devices section — see “Dust: Update on Motes”) but also nanoelectronic components for quantum computers.

The method involved heating chemical vapor in the presence of a metal catalyst, in a vacuum, to form nanowires 30 to 80 nanometers in diameter and up to 10,000 nanometers long, and nanotubes 10 to 15 nanometers in diameter and up to 5,000 nanometers long. The nanowires or tubes are formed directly on the component being assembled, and nearby components are protected from the high temperatures. Simple sensors could be built using this method within a year.

Another new method involves heating sapphire crystal to a high temperature, which causes five-nanometer-wide fracture lines that can be filled with titanium to create nanowire on a potentially large scale. Other types of crystal could also be used, but a benefit of sapphire is that it is an insulator, so together with its conductive nanowires the crystal forms a ready-made electrical network. The method could be used for practical applications within five years.

Reference: Unknown (2003). “Process Puts Nanotubes In Place.” Technology Research News, July 2; Unknown (2003). “Crystal Cracks Nurture Nanowires.” Technology Research News, July 18.

Plastic Magnets

Transparent, durable, lightweight magnets that maintain their magnetism in the presence of other magnetic fields and high temperatures could be used to modulate laser light and holograms, and as electrical insulators in sensors and actuators. The material will be ready for use in commercial products in five to ten years.

Reference: Unknown (2003). “See-Through Magnets Hang Tough.” Technology Research News, July 21.