JP2853000B2 - Electron emitting device and method of manufacturing image forming apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an electron-emitting device.

[0002]

2. Description of the Related Art Conventionally, two types of electron-emitting devices, a thermionic electron source and a cold cathode electron source, are known. Field emission type (FE), metal / insulating layer / metal type (hereinafter abbreviated as MIM), and surface conduction type electron emitting device (SC) are used as cold cathode electron sources.
E).

[0003] An example of a field emission type (FE) is disclosed in W.S.
P. Dyke & W. W. Dolan, "Field e
mission ", Advance in Elect
ronPhysics, 8, 89 (1956) and C.I. A. Spindt, “Physical prop
artists of thin film-field
emission cathodes with mo
lybdenum cones ", J. Appl. Ph.
ys. , 47, 5248 (1976).

As an example of the MIM type, C.I. A. Mea
d, "The tunnel-emission am
plier, J. et al. Appl. Phys. , 32, 6
46 (1961) and the like are known.

As an example of the SCE type, M. I. Elin
son, Radio Eng. Electron P
ys. , 10 (1965).

[0006] The SCE utilizes a phenomenon in which electrons are emitted by passing a current through a small-area thin film formed on a substrate in parallel with the film surface.

As the surface conduction electron-emitting device (SCE), a device using a SnO ₂ thin film by Elinson et al., A device using an Au thin film [G. Dittmer: "T
Hin Solid Films ", 9, 317 (19
72)], a thin film of In ₂ O ₃ / SnO ₂ [M.
Hartwell and C.M. G. FIG. Fonstad:
"IEEE Trans. ED Conf.", 519
(1975)], using a carbon thin film [Hisashi Araki]
Others: Vacuum, Vol. 26, No. 1, p. 22 (1983)] and the like.

As a typical device configuration of these surface conduction electron-emitting devices, the above-mentioned M.S. Hartwell device configuration
As shown in FIG . In FIG. 1, reference numeral 1 denotes an insulating substrate. The electron emitting portion forming thin film 2 is formed of an H-shaped metal oxide thin film or the like formed by sputtering, and the electron emitting portion 3 is formed by an energization process called forming described later. Reference numeral 4 denotes a thin film including an electron emitting portion.

Conventionally, in these surface conduction electron-emitting devices, the electron-emitting portion 3 is generally formed before the electron emission by performing an energizing process called forming on the electron-emitting portion forming thin film 2. . That is, the forming means that the voltage is applied to both ends of the electron-emitting portion forming thin film 2, and the electron-emitting portion forming thin film is locally destroyed, deformed or deteriorated, and is in an electrically high-resistance state. That is, forming the emission part 3. In the electron emitting portion 3, a crack may be generated in a part of the thin film 2 for forming the electron emitting portion, and the electron emission may be performed from the vicinity of the crack. Hereinafter, the thin film for forming the electron emitting portion including the electron emitting portion generated by the forming is referred to as a thin film 4 including the electron emitting portion.

In the surface-conduction type electron-emitting device subjected to the forming treatment, a voltage is applied to the thin film 4 including the above-described electron-emitting portion, and a current is caused to flow through the surface of the device, thereby causing the electron-emitting portion 3 to emit electrons. Things.

In manufacturing such an electron-emitting device,
It is important to reduce the variation in characteristics as much as possible. For that purpose, it is necessary to form the electron-emitting portion with good reproducibility.

As a specific method, Japanese Patent Application Laid-Open No. Sho 63-2
No. 98934 discloses that after a part of a thin film is increased in resistance,
There has been disclosed a technique for improving the positional accuracy and reproducibility with respect to the energizing direction by performing an energizing process. As a method of increasing the resistance, a method of forming a concave portion by etching, a method of depositing a mask, a method of changing the number of layers, and a method of implanting a high resistance material are disclosed.

Japanese Patent Application Laid-Open No. Hei 2-247940 discloses a technique in which a step is provided on a substrate to form an electron-emitting portion near the step. As a step type method, a method using photolithographic etching is disclosed.

[0014]

However, in the conventional method, the positional accuracy of the formation of the electron-emitting portion is not sufficient and is only on the order of submicrons, which is an obstacle to further uniforming the device characteristics.

The present invention has been made in order to improve such disadvantages of the prior art, and has provided a method of manufacturing an electron-emitting device capable of forming an electron-emitting portion with high positional accuracy on an atomic scale. It is intended to provide.

[0016]

That is, the present invention provides an insulating material.
A scanning tunneling microscope is placed on the conductive thin film formed on the substrate.
Attaching the atoms detached from the probe of the microscope;
Current flows through the conductive thin film to which the
Forming an electron emitting portion.
This is a method for manufacturing an electron-emitting device. The present invention also provides the above
Method of manufacturing image forming apparatus using method of manufacturing electron-emitting device
Is the law.

[0017]

[0018]

[0019]

EXAMPLES The present invention will be specifically described below with reference to examples.

Embodiment 1 FIG. 1 is a process chart showing an embodiment of a method for manufacturing an electron-emitting device according to the present invention. The electron-emitting device is manufactured by the following steps based on FIG.

A quartz substrate is used as the insulating substrate 11, and after sufficiently washing the substrate with an organic solvent, device electrodes 12 and 13 made of Ni are formed on the surface of the insulating substrate 11. (See FIG. 1A). At this time, the element electrode interval L is 3
μm, the width W of the device electrode is 500 μm, and its thickness d is 1000 °.

Next, a solution containing organic palladium (ccp-4230, manufactured by Okuno Pharmaceutical Co., Ltd.) is applied onto the insulating substrate 11, and then heated at 300 ° C. for 10 minutes to form palladium oxide (PdO). 3.) A conductive thin film of fine particles (average particle size: 70 °) is formed. Here, the fine particle film 14 has a width (element width) W of 300 μm, and is disposed substantially at the center of the element electrodes 12 and 13. (See FIG. 1B). The thickness of the fine particle film 14 is 10
The sheet resistance is about 0 ° and about 5 × 10 ⁴ Ω / □.

Next, a probe 15 of a scanning tunneling microscope to which tungsten atoms have been previously attached is moved to a fine particle film 14.
When the probe is slowly moved in contact with and separated from the fine particle film 14 while checking the tunnel current, tungsten fine particles 16 are formed on the fine particle film 14.
(See FIG. 1 (c)).

Next, when a pulse voltage as shown in FIG. 2 is applied between the electrode 12 and the electrode 13 and an energizing process (forming process) is performed, the structural change of the fine particle film starts from the place where the tungsten fine particles 16 are present. Occurs, and an electron emission portion 17 formed of a crack is formed. (See FIG. 1 (d)).

Here, in FIG. 2, T ₁ and T ₂ are the pulse width and pulse interval of the voltage waveform, and T ₁ is 1 in this embodiment.
ms, T ₂ are 10 ms, the peak value of the triangular wave (peak voltage during forming) is 5 V, and the forming process is performed in a vacuum atmosphere of about 1 × 10 ⁻⁶ torr for 60 seconds.

The electron-emitting portion 17 thus formed
Is a state in which fine particles mainly composed of palladium element are dispersed and arranged, and the average particle diameter of the fine particles is 30 °. The positional accuracy of the formation of the electron-emitting portion is about 100 nm when measured with a scanning tunneling microscope.

When a voltage of about 8 V or more is applied between the electron-emitting devices manufactured as described above, remarkable electron emission is observed from the cracks 17. At a device voltage of about 16 V, about 1 μA is applied. Electron emission is observed.

In this embodiment, the tungsten fine particles are arranged at one place. However, they can be arranged at a plurality of places, and can be arranged in a stepping stone shape or a linear shape. In this case, it takes time and effort to manufacture, but there is an effect of further reducing the variation of the elements.

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

As a probe of the scanning tunneling microscope, a usual material such as tungsten, platinum or the like can be used.

The method for manufacturing an electron-emitting device according to the present invention comprises:
Of course, the materials of the insulating substrate, the conductive thin film, the fine particles serving as triggers, and the electrodes in the above-described embodiments are not limited. In particular, if a specific example of a conductive thin film including an electron emitting portion is given, Pd, Ru, A
g, Au, Ti, In, Cu, Cr, Fe, Zn, S
metals such as n, Ta, W, Pb, PdO, SnO ₂ , In
Oxides such as ₂ O ₃ , PbO, Sb ₂ O ₃ , HfB ₂ , Z
borides such as rB ₂ , LaB ₆ , CeB ₆ , YB ₄ , GdB ₄ , TiC, ZrC, HfC, TaC, SiC, WC
Carbide such as Tin, nitride such as Tin, ZrN, HfN, S
semiconductors such as i, Ge, carbon, AgMg, NiCu,
Pb, Sn and the like.

The conductive thin film including the electron-emitting portion is formed by a vacuum deposition method, a sputtering method, a chemical vapor deposition method, a dispersion coating method, a dipping method, a spinner method, or the like.

In the above embodiment, a method of manufacturing one electron-emitting device has been described. However, a plurality of electron-emitting devices can be manufactured by using the method of the present invention. By arranging a plurality of electron-emitting devices on a plane, a flat display device can be configured.

The embodiment will be described below.

Embodiment 2 Next, a method of manufacturing an image forming apparatus such as a display device using the manufacturing method of the present invention will be described with reference to FIG .

In the above-described manufacturing steps of FIGS. 1A to 1C, a plurality of unformed forming electron-emitting devices 104 connected to the X-direction wiring 105 and the Y-direction wiring 106 are connected to the substrate 101. After fixing the electron source substrate disposed on the rear plate 102, a face plate 110 (formed by forming a fluorescent film 108 and a metal back 109 on the inner surface of a glass substrate 107) is formed 5 mm above the substrate 101. It is disposed with the support frame 103 interposed therebetween. Frit glass is applied to the joint between the faced plate 110, the support frame 103, and the rear plate 102, and sealed by baking at 400 ° C. to 500 ° C. for 10 minutes or more in the air or a nitrogen atmosphere. (See FIG. 4 ).

Also, the substrate 101 on the rear plate 102
Was also fixed with frit glass. In FIG. 4 , 1
04 is an electron-emitting device, 105 and 106 are wiring electrodes in the X and Y directions, respectively. In this embodiment, as described above,
The envelope 111 is composed of the face plate 110, the support frame 103, and the rear plate 102.
2 is provided mainly for the purpose of reinforcing the strength of the substrate 101. Therefore, when the substrate 101 itself has sufficient strength, the separate rear plate 102 is unnecessary, and the support frame 103 is directly sealed to the substrate 101. , The face plate 110, the support frame 103, and the substrate 101 may constitute the envelope 111.

The fluorescent film 108 is composed of only a phosphor in the case of monochrome, but in the case of a color fluorescent film, a black conductive material 112 called a black stripe or a black matrix and a phosphor 113 depending on the arrangement of the phosphors.
It is composed of The purpose of providing the black stripe and the black matrix is to make the three-color phosphors necessary for the color display black between the phosphors 113 so that the color mixture and the like become inconspicuous.
8 is to suppress a decrease in contrast due to external light reflection. In the present embodiment, the fluorescent material adopts a stripe shape, a black stripe is formed first, and the fluorescent material of each color is applied to the gap, thereby forming the fluorescent film 108. As the material of the black stripe, a material mainly containing graphite, which is generally used, is used. However, the material is not limited to this as long as it is conductive and has little light transmission and reflection.

As a method of applying the phosphor on the glass substrate 107, a precipitation method or a printing method is used in the case of monochrome, but in the present embodiment which is a color, a slurry method is used.
Even in the case of color printing, the same coating film can be obtained by using the printing method. A metal back 109 is usually provided on the inner surface side of the fluorescent film 108. The purpose of the metal back is to improve the brightness by mirror-reflecting the light emitted from the phosphor toward the inner surface side to the face plate 110 side, to act as an electrode for applying an electron beam acceleration voltage, This is to protect the phosphor from damage due to collision of negative ions generated in the enclosure. The metal back is manufactured by performing a smoothing process (usually called filming) on the inner surface of the fluorescent film after manufacturing the fluorescent film, and then performing vacuum deposition of A1.

The face plate 110 may be provided with a transparent electrode (not shown) on the outer surface side of the fluorescent film 108 in order to further enhance the conductivity of the fluorescent film 108, but in this embodiment, only a metal back is used. Omitted because sufficient conductivity was obtained. When the above-mentioned sealing is performed, in the case of color, the phosphors of each color must correspond to the electron-emitting devices, so that sufficient alignment is performed.

The atmosphere in the glass container completed as described above is exhausted by a vacuum pump through an exhaust pipe (not shown), and after reaching a sufficient degree of vacuum, the external terminals Dxl to Dxm and Dyl to Dyn. Wiring 105, 106 through
A voltage is applied in between, and the above-described forming is performed in FIG.
4 is produced.

Finally, the exhaust pipe (not shown) is welded by heating with a gas burner at a degree of vacuum of about 10 ^-6 Torr to seal the envelope. Finally, a getter process is performed to maintain the degree of vacuum after sealing. In this method, a getter disposed at a predetermined position (not shown) in an image display device is heated by a heating method such as resistance heating or high-frequency heating immediately before or after sealing to form a deposited film. Processing. The getter usually contains Ba or the like as a main component, and maintains the degree of vacuum by the adsorption action of the deposited film.

In the image forming apparatus completed as described above, the external terminals Dxl to Dx
Electrons are emitted by applying a voltage through m, Dyl or Dyn, and a high voltage of several kV or more is applied to the metal back 109 or a transparent electrode (not shown) through the high voltage terminal Hv to accelerate the electron beam, An image is displayed by colliding with the fluorescent film 108 to excite and emit light.

The configuration described above is a schematic configuration for producing an image forming apparatus. For example, the detailed parts such as the materials of each member are not limited to those described above. The arrangement form of the element 104 on the substrate 101 may be a form in which a plurality of element rows in which a plurality of electron-emitting elements are connected between a pair of wiring electrodes are arranged. In this case, the element rows are orthogonal to the element rows. A control electrode (usually called a grid) for selecting an element that causes the phosphor to emit light is arranged in the direction in which the light is emitted. As described above, the selection is appropriately made so as to be suitable for the use of the image forming apparatus.

[0057]

As described above, according to the present invention,
After processing a part of the conductive thin film using the probe of the scanning tunneling microscope, the conductive thin film is energized, and the processing location of the probe triggers the electron emission unit with atomic-scale positional accuracy. Can be formed, and there is an effect that variation in element fabrication can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a process chart showing one embodiment of a method for manufacturing an electron-emitting device of the present invention.

FIG. 2 is a diagram illustrating a waveform of a voltage pulse during a forming process according to the first embodiment of the present invention.

FIG. 3 shows a configuration of a conventional surface conduction electron-emitting device.
FIG.

FIG. 4 is a configuration of a simple matrix type display panel.
FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulating substrate 2 Thin film for electron emission part formation 3 Electron emission part 4 Thin film including electron emission part 11 Insulating substrate 12 Element electrode 13 Element electrode 14 Conductive thin film 15 Scanning tunnel microscope probe 16 Fine particles 17 Electron emission part

Continuation of the front page (72) Inventor Hideyuki Sugioka 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Masahiro Okuda 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Shigeki Matsuya 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Yoshiyuki 3-30-2 Shimomaruko 3-chome, Ota-ku, Tokyo Inside Canon Inc. (56) Reference References JP-A-63-298934 (JP, A) JP-A-4-355914 (JP, A) Shigeyuki Hosoki and Tsuyoshi Hasegawa, "Surface Decoration Using Scanning Tunneling Microscope-Atomic Manipulation of Molybdenum Disulfide- "Applied Physics, February 1993, Vol. 62, No. 2, p. 155 to 159 (58) Fields investigated (Int. Cl. ⁶ , DB name) H01J 9/02 H01J 1/30 H01J 37/30 JICST file (JOIS)

Claims (2)

(57) [Claims] 1. On a conductive thin film formed on an insulating substrate
Then, the atoms detached from the tip of the scanning tunneling microscope are
Attachment step and energizing the conductive thin film to which the atoms are attached
Forming an electron emitting portion on the conductive thin film.
A method for manufacturing an electron-emitting device. 2. A method for manufacturing an electron-emitting device according to claim 1.
And a method of manufacturing an image forming apparatus using the same.