Thursday, May 04, 2006


For all of the talk of nanotechnology in the press there are actually relatively few patents related to nanotechnology. If one were to consider any patent claiming any one of

a) a new structure or material including a nanoparticle, nanotube, nanowire, quantum dot, or other nanostructure, or
b) a new method or tool for manufacturing or characterizing a structure as in a), or
c) a new method of use of a structure as in a)

as a "nanotechnology" patent and then compared the number of these "nanotechnology" patents with the total number of patents issued by the US in one year (~180,000) the ratio would be far less than 1%.

This combined with the general consensus that nanotechnology will be a large driver of the future economy leads one to believe that the few companies holding these relatively rare patents may be in a very powerful position. So let me start this blog with an analysis of what could be one of the most valuable patents of these rare and valuable patents - US RE38,561

This patent is fairly interesting, not only because of it's potential value, but because it is one of the few nanotech. patents to undergo a reissue examination. Claim 10 reads-

10. A field emission cathode comprising an electron-emitting part of the cathode formed at least in part as a carbon nano-cylinder.

Basically this claim seems to cover any cylindrical carbon nanostructure (such as a carbon nanotube) capable of electron emission. A text book by M.Meyyappan of NASA Ames Research Center published last year and entitled "Carbon Nanotubes: Science and Applications" has an entire chapter devoted to the applications of electron emitting carbon nanotubes. This chapter cites a paper in Science published Nov.17, 1995 entitled "A Carbon Nanotube Field-Emission Electron Source" as the first discussion of this use of nanotubes in the scientific literature. The priority date of RE38,561 is at least Feb.22,1995 (PCT filing date). Therefore, although extremely broad, this patent claim does not appear defective.

The potential analogy between this patent and industry may not be so different than the analogy between the first laser patent and industry. The case of the laser has shown wide ranging applications (such as digital printing, eye surgery, fiber optic communication, etc.) may emerge from the invention of a single device. Electron emitting nanotubes are similarly drawing interest in a variety of devices such as flat panel displays, electron microscopy, lithography tools, and electronic switching devices.