Coating processes – Electrical product produced – Electron emissive or suppressive
Reexamination Certificate
1996-04-02
2001-10-02
Bell, Janyce (Department: 1762)
Coating processes
Electrical product produced
Electron emissive or suppressive
C427S064000, C427S226000, C427S343000
Reexamination Certificate
active
06296896
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the manufacturing method of an electron-emitting device, and more particularly, to electron sources, display panels, and image forming apparatuses, employing the aforementioned electron image device.
2. Related Background Art
Conventionally, two types of electron emission devices have been known; i.e., thermionic type and cold cathode type. Types of cold cathode electron-emitting devices include; field emission type devices (hereafter referred to as “FE type device”), metal/insulator/metal type devices (hereafter referred to as “MIM device”), surface conduction electron-emitting devices (hereafter referred to as “SCE device”), etc.
Known examples of reports of FE type devices include: W. P. Dyke & W. W. Dolan, “Field emission”, Advance in Electron Physics, 8, 89(1956); and “Physical properties of thin-film field emission cathodes with molybdenum cones”, J. Appl. Phys., 47, 5248(1976); etc. Known examples of reports of MIM devices include: C. A. Mead, “The tunnel-emission amplifier” A. Appl. Phys., 32. 646(1961); etc. Known examples of reports of SCE type devices include: M. I. Elinson, Radio Eng. Electron Phys., 10, (1965); etc.
The SCE device takes advantage of the phenomena where electron emission occurs when an electric current is caused to flow parallel to a thin film, this thin film of a small area being formed upon a substrate. As for examples of such surface conduction electron-emitting devices, in addition to the device by the aforementioned Elinson et al using SnO
2
thin film, there have been reported those which use Au thin film [G. Dittmer: “Thin Solid Films”, 9,317(1972)], In
2
O
3
/SnO
2
thin film [M. Hartwell and C. G. Fonstad: “IEEE Trans. ED Conf.”, 519(1975)], and carbon thin film [Hisashi Araki et al: Shinku, Volume 26, No. 1, page 22 (1983)], etc.
FIG. 18
illustrates the construction of the aforementioned Hartwell device as a classical example of such a surface conduction electron-emitting device. In this Figure, the numeral
1
denotes a substrate. The numeral
4
denotes an electroconductive film formed by sputtering in an H-shaped form of metal oxide thin film, etc., and the electron-emitting region
5
is formed by a later-mentioned current conduction treatment called energization forming. In this Figure, the spacing L between the device electrodes is set to be 0.5 to 1 mm, and the device length W′ is set at approximately 0.1 mm. The form of the electron-emitting region
5
has been illustrated in a type drawing.
Conventionally, with these surface conduction electron-emitting devices, it has been common to form the electron-emitting region
5
by conducting a current conduction treatment called energization forming on the electroconductive film
4
beforehand; i.e., energization forming refers to the process of applying either a direct current or an extremely slow rising voltage, such as around 1V/minute, to both edges of the electroconductive film
4
so as to cause local destruction, deformation, or deterioration, thereby forming an electron-emitting region
5
having high electrical resistance. Further, regarding the electron-emitting region
5
, a fissure has formed at one portion of the electroconductive film
4
, and electron emission occurs from the proximity of this fissure. The member which has been subjected to local destruction, deformation, or deterioration, by means of energization forming upon the conductive film is referred to as the electron-emitting region
5
, and the conductive film
4
upon which the electron-emitting region
5
has been formed by means of energization forming is referred to as the electroconductive film
4
which contains the electron-emitting region
5
. The aforementioned surface conduction electron-emitting device which has been subjected to energization forming one where voltage is applied to the electroconductive film
4
which contains the electron-emitting region
5
, and electrical current is caused to flow through the aforementioned device, thereby causing emission of electrons from the electron-emitting region
5
.
Further, the aforementioned surface conduction electron-emitting device has the advantage of enabling arrayed formation of a great number of devices over a wide area, due to the construction thereof being simple and the manufacturing thereof being relatively easy. Accordingly, many applications for employing this advantage have been researched, a few examples being charged beam source and display apparatuses. An example of a great number of surface conduction electron-emitting devices being arrayed is the electron source of the so-called ladder-type device, wherein, as described later, both edges of individual surface conduction electron-emitting devices arrayed in a parallel manner are wired together by means of wiring (common wiring) so as to create a row, and many such rows being arrayed (e.g. Japanese Patent Laid-Open Application No. 1-031332, Japanese Patent Laid-Open Application No. 1-283749, Japanese Patent Laid-Open Application No. 2-257552, etc.). Also, while in recent years image forming apparatuses such as display apparatuses which are flat-type display apparatuses employing liquid crystal have become commonplace in the stead of CRT apparatuses, such flat-type display apparatuses employing liquid crystal have problems such as requiring back lightning due to not being emission type, and development of an emission type display apparatus has been awaited. An example which can be given of an emission type display apparatus is an image-forming apparatus with a display panel which is comprised of an electron source of many arrayed surface conduction electron-emitting devices, and fluorescent substance which is caused to emit visible light by means of the electrons emitted from the electron source (e.g. U.S. Pat. No. 5066883).
The known method employed for the manufacturing of electron-emitting devices such as described above has been a photo-lithographic process according to known semiconductor processes.
While the aforementioned surface conduction electron-emitting device can be applied to image-forming apparatuses and other such apparatuses by means of creating and arraying a great number of such surface conduction electron-emitting devices upon a substrate with a wide area, such an arrangement manufactured with known photo-lithographic processes would result in extremely high costs. Accordingly, it has been necessary to employ a manufacturing method with lower costs. To this end, a method has been suggested as a method for forming such devices on a substrate with a wide area, wherein printing technology is employed for forming the electrodes
2
and
3
, and formation of the electron-emitting film
4
is conducted by employing an ink-jet method in which droplets of a solvent containing organic metal compounds are deposited onto the substrate in a partial manner (e.g., Japanese Patent Application No. 6-313439 and Japanese Patent Application No. 6-313440).
Now, description of an overview of the manufacturing process for electron-emitting devices employing printing technology and ink-jet method will be given with reference to
FIGS. 3A through 3E
.
1) An insulating substrate
1
is thoroughly washed with detergent, pure water, and organic solvent, following which device electrodes
2
and
3
are formed upon the surface of the aforementioned insulating substrate
1
, employing screen printing technology or offset printing technology (FIG.
3
A).
2) Droplets of a solution containing such as organic metal compounds, for example, are deposited at the gap portion of the device electrodes
2
and
3
on the insulating substrate, employing droplet-depositing means, so that the deposited droplets connect both electrodes upon which they are deposited. This substrate is dried and baked, so as to form the electroconductive thin film
4
for forming the electrode-emitting region (FIG.
3
D).
However, depositing droplets upon the printed electrodes employing an ink-jet method re
Miura Naoko
Takahashi Yasuo
Bell Janyce
Canon Kabushiki Kaisha
Fitzpatrick ,Cella, Harper & Scinto
LandOfFree
Manufacturing method for electron-emitting device, electron... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Manufacturing method for electron-emitting device, electron..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Manufacturing method for electron-emitting device, electron... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2613219