Coating processes – Electrical product produced – Electron emissive or suppressive
Patent
1998-05-12
1999-09-07
King, Roy V.
Coating processes
Electrical product produced
Electron emissive or suppressive
427226, 427435, 427436, 427125, 445 50, 445 51, B05D 512, H01J 902
Patent
active
059484659
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The invention generally relates to a process for attaching an electron field emitter particulate material to a substrate. In particular, the invention relates to a process for forming a thin metal layer to attach electron field emitter particulate material to a substrate thereby producing a field emitter cathode.
BACKGROUND OF THE INVENTION
Field emission electron sources, often referred to as field emission materials or field emitters, can be used in a variety of electronic applications, e.g., vacuum electronic devices, flat panel computer and television displays, emission gate amplifiers, klystrons and lighting devices.
Display screens are used in a wide variety of applications such as home and commercial televisions, laptop and desktop computers and indoor and outdoor advertising and information presentations. Flat panel displays are typically only a few inches thick in contrast to the deep cathode ray tube monitors found on most televisions and desktop computers. Flat panel displays are a necessity for laptop computers, but also provide advantages in weight and size for many of the other applications. Currently laptop computer flat panel displays use liquid crystals which can be switched from a transparent state to an opaque state by the application of small electrical signals. It is difficult to reliably produce these displays in sizes larger than that suitable for laptop computers.
Plasma displays have been proposed as an alternative to liquid crystal displays. A plasma display uses tiny pixel cells of electrically charged gases to produce an image and requires relatively large electrical power to operate.
Flat panel displays having a cathode using a field emission electron source, i.e., a field emission material or field emitter, and a phosphor capable of emitting light upon bombardment by electrons emitted by the field emitter have been proposed. Such displays have the potential for providing the visual display advantages of the conventional cathode ray tube and the depth, weight and power consumption advantages of the other flat panel displays. U.S. Pat. Nos. 4,857,799 and 5,015,912 disclose matrix-addressed flat panel displays using micro-tip cathodes constructed of tungsten. molybdenum or silicon. WO 94-15352, WO 94-15350 and WO 94-28571 disclose flat panel displays wherein the cathodes have relatively flat emission surfaces.
Certain materials exhibiting electron field emission are readily produced as powders (i.e., particulate material). In order to use such electron emitting powder materials in an electron field emitter cathode it is necessary to attach the particulate emitting material to a substrate so that it is anchored to the substrate without significantly decreasing the emission properties of particulate material.
Clearly, what is needed is a process for making a field emitter cathode using a particulate field emitter material. Other objects and advantages of the present invention will become apparent to those skilled in the art upon reference to the attached figures and detailed description of the invention which hereinafter follows.
SUMMARY OF THE INVENTION
The present invention provides a process for making a field emitter cathode utilizing electron emitting particulate material (i.e., powder) by attaching said particulate material to a substrate using an electron transporting material. Preferably, the electron transporting material comprises a thin metal layer.
In another aspect of the invention, the invention provides a process for making a field emitter cathode utilizing electron emitting particulate material (i.e., powder). The process comprises the steps of: emitting powder onto the surface of the substrate, the metal compound chosen because it is readily reduced to the metal, and deposited thereon to reduce the metal compound to the metal, with the temperature and the time of heating chosen to result in the complete reduction of the metal compound.
The resulting product is a substrate coated with a thin layer of the metal with an electron emitting
REFERENCES:
patent: 4857799 (1989-08-01), Spindt et al.
patent: 5015912 (1991-05-01), Spindt et al.
patent: 5129850 (1992-07-01), Kane et al.
patent: 5199918 (1993-04-01), Kumar
patent: 5578901 (1996-11-01), Blancher-Fincher et al.
patent: 5616368 (1997-04-01), Jin et al.
patent: 5619093 (1997-04-01), Glesener et al.
L. A. Chernozatonskii, et al., Electron Field Emission From Nanofilament Carbon Films, Chemical Physics Letters, 233, 63-68, Feb. 3, 1995.
Chernozatonskii et al., Nanotube Carbon Structure Tips--A Source of High Field Emission of Electrons, Mat. Res. Soc. Symp. Proc., 359, 99-104, 1995 no month data.
B. H. Fishbine et al., Buckytube Cold Field Emitter Array Cathode Experiments, Mat. Res. Soc. Symp. Proc., 359, 93-98, 1995 no month data.
Kratschmer et al., Solid C60: A New Form of Carbon, Nature, vol. 347, 354-358, Sep. 27, 1990.
Walt A. de Heer et al., Carbon Onions Produced By Heat Treatment of Carbon Soot and Their Relation To The 217.5 nm Interstellar Absorption Feature, Chemical Physics Letters, 207, 480-486, May 28, 1993.
D. Urgate, High-Temperature Behaviour of "Fullerene Black", Carbon, vol. 32, No. 7, 1245-1248, 1994 No month data.
Davanloo et al., Laser Plasma Diamond, J. Mater. Res., vol. 5, No. 11, 2398-2404, Nov., 1990.
Blanchet-Fincher Graciela Beatriz
Herron Norman
Holstein William Leo
Subramoney Shekhar
E. I. Du Pont de Nemours and Company
King Roy V.
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