TEMPE, Arizona -- Motorola Labs, the applied research arm of Motorola Inc., said Tuesday (July 1, 2003) that building on its ability to make carbon nanotubes (CNTs) at low temperature with controlled dimensions, it has made progress in applying CNTs to large flat-panel displays and that licensing discussions have already started.
Motorola has dubbed the application "nano emissive display" or NED, and claims the technology should allow manufacturers to create flat displays with the image quality of plasma and liquid crystal displays but at lower cost. Motorola said that displays of greater than 50-inch diagonal size and just one-inch deep might be possible and that the technology could be applied to billboards.
However the company did not say what progress had been made or whether a nano-emissive display has been successfully created.
Discussions with electronics manufacturers in Europe and Asia to license the technology for commercialization, are currently taking place, Motorola said.
Carbon nanotubes, or CNTs, are sheets of carbon atoms rolled up into a tube less than a nanometer in diameter. CNTs possess a many useful properties, including that they can be doped to produce semiconducting devices. However the ability to control the length, diameter and orientation of the CNTs, and their connection to silicon substrates and metallic contacts has proved troublesome.
Although Motorola Labs does not go into detail about NED, it would seem from the name chosen that Motorola is using CNTs as a source of cold electrons that can move across a vacuum before exciting a phosphor, but that can be gated on a color pixel basis. Similar field emission displays have been constructed before but using etched silicon micrometer-scale tips as the source of electron emission.
The exposed ends of nanometer-scale tubes of carbon could replace the silicon micro-tips although the vulnerability of the carbon nanotubes to manufacturing processes has been a hurdle to this.
Motorola claims to have developed a process to grow CNTs at low temperatures. As a result it becomes easier to bond CNTs to glass substrates or silicon layers that are intolerant of heat. Motorola also claims to have created a method to place CNTs individually and precisely on a surface, in addition to controlling their length and diameter.
Other attempts in this field utilize a 'paste' or 'print' method of applying CNTs, which to date, have not been able to provide the same level of display image quality, or the potential cost savings of Motorola's NED process, the company said.
However, Motorola did not provide any information on its method of applying CNTs nor did it discuss the size or resolution of any demonstrator display that may have been built.
