NanoDiamond FED
--The promise of FED fulfilled

Genuine Diamond Emitters--the key to FED Success

An SEM image of diamond crystals in the size range of 250 – 750 nm, following lithiation.  

Bristol University, UK

New Diamond-based Field Emitter for FEDs 
                                          
A new high performance nanodiamond cathode material for flat panel displays has been demonstrated by a team at the University of Bristol, led by Dr Neil Fox. Based on single crystal nanodiamonds derived from inexpensive industrial diamond grit, the new material has enhanced electrical properties making it a highly efficient electron emitter. Processing with lithium turns the nanodiamonds into a low work-function material. The resulting dry powder is easily deposited onto cathode structures to create electron emitters.

Small voltages are required to induce free electrons to be emitted. Brightness uniformity, emission current stability, freedom from scintillation, CMOS voltage application, and long lifetime, are all essential properties of the new material.

NanoDiamond Emitter Highlights

1. The new field emitters (FEs) are 500 nanometer-size single crystal diamonds doped with lithium. 
2. Their  field emission properties are at least equal (and we believe substantially superior) to those of carbon nanotubes. 
3.  The IV diagram (below) shows that the low voltage threshold and steep current curve enables the use of CMOS drivers for FED application. 
4.  The photograph (below) shows the appearance of the nanodiamonds. They are approximately cubic in shape. Particle size grading ensures uniformity and freedom from irregular shapes or sizes. 
5.  Field emission takes place from various surface areas, that is, the facets of the entire crystal in a totally stable, fluctuation-free manner.  (Unlike the unstable point-source emission from metal tips and CNTs.) Emission is free of scintillation without the use of a ballast layer. 
6.  The lithiation process, which imparts high electrical conductivity to the diamonds,  is  simple and quite repeatable. Nanocrystal batches of similar commercial grades from several suppliers produced consistently identical results. 
7.  The industrial grade diamond material cost is less than $1 per carat. Total utilization cost is approximately$0.20 per square meter. 
8.  Diamond properties of chemical and physical stability are inherent in this new FE. In processing, for example, FE coated cathodes can be air-baked at 450C without effect. 
9.  After lithiation the nanodiamonds are in the form of a fine, free-flowing powder, which can be applied to cathode substrates by various printing methods. Dry spray is recommended, to avoid liquid-born deposits or coatings. 
10. The FE IP is straightforward, with no third party connections of any kind. An extensive legal analysis of diamond and diamond-like emitter patents indicates that there are no competing patents to impede this unique process.