Saturday, September 09, 2006

US Patent 7102157 - Nanotube Vacuum Electronics

Over the past fifty years vaccum devices have been mostly replaced by solid state devices in electronics applications. However, vacuum devices have certain advantages such as high frequency operation without the difficulties of sub-micron gate lengths. While vacuum electronics has been limited by the size of the cathode, the ability of carbon nanotubes to act as electron emitters has circumvented this problem. This patent proposes a triode configuration using nanotube cathodes. Claim 1 reads:

1. A triode, comprised of the following elements: a nanotube placed on the insulating substrate and having two metal contacts on top of it; first contact is placed at the end of the nanotube, while the second contact is placed essentially in the middle of the nanotube, on top of the insulating layer preliminary disposed on the nanotube; both said metal contacts are connected respectively to the first and second electrodes; the third electrode is placed next to the second electrode, on the plane below the plane of said second electrode; the nanotube is placed in the direction normal to the edge of the first electrode neighboring the second electrode; one of the tips of the nanotube is left exposed and protrudes into the area of the third electrode.