Electric lamp and discharge devices – With luminescent solid or liquid material – Vacuum-type tube
Reexamination Certificate
2000-02-25
2003-10-14
O'Shea, Sandra (Department: 2875)
Electric lamp and discharge devices
With luminescent solid or liquid material
Vacuum-type tube
C313S336000, C313S310000
Reexamination Certificate
active
06633118
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electron-emitting device, an electron source formed of the electron-emitting device and an image-forming apparatus such as a display device to which the electron source is applied, and more particularly to a surface conduction electron-emitting device with a novel structure, an electron source formed of the surface conduction electron-emitting device, and an image-forming apparatus such as a display device to which the electron source is applied.
2. Related Background Art
The surface conduction electron-emitting device utilizes a phenomenon in which a current is made to flow in an electroconductive film formed on a substrate to emit electrons.
As examples of the surface conduction electron-emitting device, there have been reported a surface conduction electron-emitting device using an SnO
2
film (M. I. Elinson Radio Eng. Electron Phys., 10, 1290, (1965)), a surface conduction electron-emitting device using an Au thin film (G. Ditmmer, Thin Solid Films, 9,317 (1972)), a surface conduction electron-emitting device using an In
2
O
3
/SnO
2
thin film (M. Hartwell and C. G. Fonsted, IEEE Trans. ED Conf., 519 (1975)), a surface conduction electron-emitting device using a carbon thin film (Hisashi Araki, et al: Vacuum, Vol. 26, No. 1, P. 22 (1983)), and so on.
In those surface conduction electron-emitting devices, generally an energization operation called “forming” is conducted on the electroconductive film before electron emission to come to a state in which electrons are emitted.
In the specification, the term “forming” means that a constant voltage, or a voltage that slowly rises at a rate of, for example, about 1 V/min, is applied to both ends of the electroconductive film so that a current flows in the electroconductive film with the result that the electroconductive film is locally destroyed, deformed or affected into an electrically high resistant state by which electron emission occurs.
It is presumed that the above operation permits the electroconductive film to be partially fissured, and a phenomenon of the electron emission is caused by the existence of the fissure. Where the electron emission actually occurs is not completely elucidated, but the fissure portion and a region surrounding the fissure portion may be called “electron-emitting portion” for convenience.
The applicant of the present invention has already proposed many types of surface conduction electron-emitting devices. For example, that the above “forming” operation is preferably conducted by applying a pulse voltage to the electroconductive film has been disclosed in Japanese Patent No. 2854385, U.S. Pat. Nos. 5,470,265, 5,578,897, and so on.
In this example, the waveforms of the pulse voltage may be produced by a method in which peak values are held constant as shown in
FIG. 5A
, or a method in which the peak values are gradually increased. Thus, the waveforms can be appropriately selected taking the configuration and the material of the device, the forming conditions and so on into consideration.
Also, there has been proved that the pulse voltage is repeatedly applied to the electron-emitting device in an atmosphere containing an organic material therein subsequently to the above forming operation, as a result of which a current that flows in the device (device current If) and a current produced with electron emission (emission current Ie) are increased. This operation is called “activation”.
The above operation is that a deposit mainly containing carbon therein is formed in a region including the fissure formed in the electroconductive film through the forming operation, which is disclosed in detail in Japanese Patent Application Laid-Open No. 7-235255, etc.
In the case where the above-described surface conduction electron-emitting device is applied to an image-forming apparatus or the like, a lower power consumption and a higher luminance are further demanded.
Accordingly, as the performance of the electron-emitting device, a demand has been made to heighten the ratio of the emission current Ie to the device current If, that is, the electron emission efficiency as compared with that in the conventional device.
Also, it is needless to say that in improving the above performance, a change of the performance with a time which results from continuing the electron emission must be prevented from increasing more than that in the conventional device.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an electron-emitting device excellent in the electron emission characteristic, an electron source using the electron-emitting device, and an image-forming apparatus using the electron source.
In order to achieve the above object, according to the present invention, there is provided an electron-emitting device comprising: a substrate; a pair of electroconductors disposed on a substrate so as to face each other; and a pair of deposit films connected to the pair of electroconductors, respectively, disposed with a gap therebetween and mainly containing carbon, wherein lead is contained in the deposit films in a rate of from 1 mol % to 5 mol % with respect to carbon.
Also, according to the present invention, there is provided an electron-emitting device comprising: a pair of device electrodes disposed on a substrate so as to face each other; electroconductive films connected to the pair of device electrodes and having a fissure between the pair of device electrodes; and a deposit film formed in the fissure and on a region including the fissure, having a gap narrower in width than that of the fissure within the fissure and mainly containing carbon, wherein lead is contained in the deposit film in a rate of from 1 mol % to 5 mol % with respect to carbon.
REFERENCES:
patent: 5470265 (1995-11-01), Nomura et al.
patent: 5530314 (1996-06-01), Banno et al.
patent: 5578897 (1996-11-01), Nomura et al.
patent: 6208071 (2001-03-01), Nishimura et al.
patent: 0 660 357 (1995-06-01), None
patent: 7-235255 (1995-09-01), None
patent: 2854385 (1998-11-01), None
M.I. Elinson et al., “The Emission of Hot Electrons and The Field Emission of Electrons From Tin Oxide”, Radio Engineering and Electronic Physics, Jul. 1965, pp. 1290-1296.
H. Araki, “Electroforming and Electron Emission of Carbon Thin Films”, Journal of the Vacuum, Society of Japan, 1983, pp. 22-29 (with English Abstract on p. 22).
G. Dittmer, “Electrical Conduction and Electron Emission of Discontinuous Thin Films”, Thin Solid Films, 9, 1972, pp. 317-328.
M. Hartwell, “Strong Electron Emission From Patterned Tin-Indium Oxide Thin Films”, IEDM, 1975, pp. 519-521.
Kobayashi Tamaki
Mogi Satoshi
Yamamoto Keisuke
O'Shea Sandra
Truong Bao
LandOfFree
Electron-emitting device, electron source using the... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electron-emitting device, electron source using the..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electron-emitting device, electron source using the... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3141669