Back to results
US 12,462,999 B2Granted
Methods of forming a field emission cathode
AssigneeNCX Corporation
InventorCheng Qian
Life of this patent
Estimating the term…
Abstract
A method for fabricating an electron field emission cathode, the field emission cathode including a substrate having a field emission material layer engaged therewith, where the field emission material incorporates a carbon nanotube material and is produced via a sol-gel process to improve field emission characteristics of the field emission cathode and field emission cathode devices implementing such cathodes.
Claims22
A method of forming a field emission cathode, comprising:
- mixing a plurality of carbon nanotubes and a solution at a particular ratio to form a base mixture, the solution comprising a water stable conducting polymer in a liquid medium;
- exposing the base mixture to a first ultrasonic dispersion process at a power of greater than 1 W/cm2 and at a frequency of 20-50 kHz;
- introducing at least one matrix particle to the base mixture to form a field emission material precursor;
- exposing the field emission material precursor to a second ultrasonic dispersion process at a power of less than 1 W/cm2 and at a frequency of greater than 50 kHz to form a stable solution of the field emission material precursor;
- introducing a polar additive into the stable solution of the field emission material precursor to form a sol solution as a final field emission material precursor;
- depositing a layer of the final field emission material precursor on at least a portion of a substrate;
- drying the layer of the final field emission material precursor and the substrate at a temperature of 30° C. to 150° C. at atmosphere or under a vacuum such that the layer of the final field emission material precursor forms a uniform gel layer on the substrate;
- annealing the gel layer and the substrate at a temperature of 500° C. to 1000° C. under a vacuum such that the gel layer forms a field emission material;
- and
- activating the field emission material to form the field emission cathode.
7 more elements
A method of forming a field emission material precursor, comprising:
- introducing a plurality of carbon nanotubes into a liquid medium;
- introducing a water stable conducting polymer into the liquid medium comprising the plurality of carbon nanotubes, wherein the plurality of carbon nanotubes is present at a particular ratio to a solution comprising the liquid mixing the plurality of carbon nanotubes and the water stable conducting polymer in the liquid medium via a first ultrasonic dispersion process at a power of greater than 1 W/cm2 and at a frequency of 20-50 kHz to form a base mixture;
- introducing at least one matrix particle into the base mixture;
- exposing the base mixture including the at least one matrix particle to a second ultrasonic dispersion process at a power of less than 1 W/cm2 and at a frequency of greater than 50 kHz to form a stable solution of a field emission material precursor;
- and
- introducing a polar additive into the stable solution of the field emission material precursor to form a final field emission material precursor.
3 more elements
Dependencies are inferred from the claim text.