JP4083611B2 - Manufacturing method of cold cathode electron source - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a cold cathode electron source including a carbon nanotube as an electron emission source.
[0002]
[Prior art]
In recent years, a cold cathode electron source using carbon nanotubes (hereinafter referred to as “CNT”) as an electron emission source has been proposed as a field emission type cold cathode electron source employed in a display device such as a field emission display (FED). Has been.
[0003]
The CNT has a tube shape with a length of several μm, and has a characteristic that an electric field tends to concentrate on the tip of the CNT and electrons are easily emitted. Therefore, good emission characteristics can be obtained by using CNT as an electron emission source.
[0004]
Patent Document 1 discloses a manufacturing method of a cold cathode electron source using CNT as an electron emission source. In the technique described in Patent Document 1, an electron emission portion made of a bundle paste including a bundle composed of a plurality of CNTs is formed on a substrate, and the electron emission portion is irradiated with a laser to emit electrons. Substances other than the bundles in the part are selectively removed, and carbon components other than the CNTs in the bundle are selectively removed to expose the CNTs.
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-36243 [0006]
[Problems to be solved by the invention]
In general, not only standing CNTs but also lying CNTs exist in the electron emission portion formed on the substrate. Therefore, in order to improve the emission characteristics, the leading edge of the lying CNTs is provided. Need to be exposed. However, in the technique described in Patent Document 1, since the CNT is exposed as it is, it is difficult to expose the tip of the lying CNT, and a sufficient emission current cannot be obtained.
[0007]
Accordingly, the present invention has been made in view of the above problems, and an object thereof is to provide a manufacturing technique capable of improving the emission characteristics of a cold cathode electron source.
[0008]
[Means for Solving the Problems]
A manufacturing method of a cold cathode electron source according to the present invention is a manufacturing method of a cold cathode electron source including an electron emitting portion containing carbon nanotubes and carbon impurities that emit electrons, and (a) a step of forming a cathode electrode; (B) forming the electron emitting portion on the cathode electrode; (c) forming a gate structure surrounding the electron emitting portion on the cathode electrode; and (d) forming the electron emitting portion on the cathode electrode. 0 running dry etching, thereby exposing the carbon nanotubes are buried in the carbon impurities from the carbon impurities, after (e) the step (c) and (d), the electron emitting portion for .7MW / cm ² by irradiating a laser with a smaller irradiation density than the carbon impure said carbon nanotubes are buried in the carbon impurity And a step of further exposed from.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
1-6 is sectional drawing which shows the manufacturing method of the cold cathode electron source which concerns on Embodiment 1 of this invention in order of a process. The cold cathode electron source according to the first embodiment is a field emission type electron source and has, for example, a bipolar structure. And it can apply to display apparatuses, such as FED. Below, with reference to FIGS. 1-6, the manufacturing method of the cold cathode electron source which concerns on this Embodiment 1 is demonstrated.
[0011]
First, as shown in FIG. 1, for example, a cathode electrode 2 having a size of 2 mm square is formed on an insulating substrate 1. Then, the conductive paste 6 containing a plurality of CNTs having a length of several μm is patterned on the cathode electrode 2 by a screen printing method. In addition to CNT, the conductive paste 6 used here includes carbon impurities such as amorphous carbon and other carbon products, organic solvents such as butyl carbitol, binders such as ethyl cellulose, and dispersants such as honogenol. include. Moreover, the thickness of the conductive paste 6 after printing is 2 to 4 μm, for example, and the cathode electrode is made of, for example, ITO (Indium Titanium Oxide).
[0012]
Next, the patterned conductive paste 6 is dried in an air atmosphere at about 120 ° C. and further baked in an air atmosphere at 500 to 550 ° C. As a result, the organic solvent, binder and dispersant in the conductive paste 6 almost disappear, and the electron emission portion 3 containing the CNTs 4 and the carbon impurities 5 is formed on the cathode electrode 2 as shown in FIG. . FIG. 3 shows an image when the electron emission portion 3 shown in FIG. 2 is photographed from above using an electron microscope. As shown in FIGS. 2 and 3, most of the CNTs 4 are buried in the carbon impurities 5 in the electron emission portion 3. Therefore, only the tips of some of the CNTs 4 are exposed from the carbon impurities 5, and most of the tips of the CNTs 4 are not exposed from the carbon impurities 5. As shown in FIG. 2, the electron emission unit 3 includes not only the standing CNT 4 but also the lying CNT 4.
[0013]
Next, as shown in FIG. 4, the tip of the CNT 4 buried in the carbon impurity 5 by partially irradiating the carbon impurity 5 by irradiating the electron emission part 3 with a laser from above in the atmosphere. To expose. At this time, the laser irradiation density (also referred to as “laser peak intensity”) is set to 0.7 MW / cm ² or more. Further, as the laser, for example, an excimer laser with a wavelength of 308 nm is employed, and laser irradiation is performed for one shot with a pulse width of 17 nsec.
[0014]
FIG. 5 shows an image when the electron emission section 3 shown in FIG. 4 is photographed from above using an electron microscope. As shown in FIGS. 4 and 5, when the laser irradiation density is set to 0.7 MW / cm ² or more, the CNT 4 is deformed by the heat generated in the electron emission portion 3 by the laser irradiation, and is in a lying state before the laser irradiation. The CNT4 which has been in a standing state. Therefore, in the electron emission part 3, the ratio of CNT4 in a standing state is increased more than before laser irradiation.
[0015]
Next, as shown in FIG. 6, an anode electrode 9 facing the cathode electrode 2 with a predetermined distance is disposed. In the first embodiment, the distance between the cathode electrode 2 and the anode electrode 9 is set to 100 μm.
[0016]
In this way, a cold cathode electron source having a field emission type bipolar structure is completed.
[0017]
FIG. 7 is a diagram showing emission characteristics of the cold cathode electron source manufactured as described above. The horizontal axis shows the laser irradiation density when the electron emission part 3 is irradiated with laser to expose the CNTs 4, and the vertical axis shows the emission current of the cold cathode electron source manufactured at the laser irradiation density. .
[0018]
The data shown in FIG. 7 is measured at room temperature and a pressure of 1.33 × 10 ⁻⁶ Pa, and the voltages of the cathode electrode 2 and the anode electrode 9 at the time of measurement are set to 0V and 600V, respectively. Also, the alternate long and short dash line in the figure shows the emission current when the carbon impurities 5 are removed and the CNTs 4 are exposed by conventional tape polishing. That is, the broken line in the figure indicates the emission current when the CNT 4 buried in the impurity is exposed as it is, as in the technique described in Patent Document 1.
[0019]
As shown in FIG. 7, when the laser irradiation density is set to 0.7 to 8.6 MW / cm ² , an emission current larger than that obtained when the CNT 4 is simply exposed can be obtained. The reason for this will be described below.
[0020]
As described above, when the laser irradiation density is set to 0.7 MW / cm ² or more, the CNT 4 that was in the lying state before the laser irradiation stands. In the electron emission part 3, when the number of standing CNTs 4 increases, the number of electrons traveling in the same direction among the electrons output from the tips of the CNTs 4 increases, so that the emission current increases. As the laser irradiation density increases, the number of standing CNTs 4 increases, and the emission current also increases accordingly. When the laser irradiation density becomes larger than a certain value, the number of standing CNTs 4 does not increase any more.
[0021]
On the other hand, as the laser irradiation density increases, the number of CNTs 4 destroyed by the laser increases. Therefore, when the laser irradiation density is larger than a certain value, the emission current reduction effect due to the destruction of the CNT4 becomes larger than the emission current increase effect due to the increase in the number of standing CNT4. The laser irradiation density takes a local maximum value, and decreases as the laser irradiation density increases. In the data shown in FIG. 7, when the laser irradiation density is 5.2 MW / cm ² , the emission current takes the maximum value and shows the best emission characteristics.
[0022]
Since the emission current decreases as the laser irradiation density increases, if the laser irradiation density becomes larger than a certain value, the emission current decreases as compared with the conventional technique in which the CNT 4 is simply exposed. In the data shown in FIG. 7, if the laser irradiation density is 8.6 MW / cm ² or less, the emission current is larger than that of the prior art.
[0023]
Thus, by setting the laser irradiation density to 0.7 MW / cm ² or more, it becomes possible to easily stand up the CNT 4 that was in the lying state before the laser irradiation. Even if the CNT 4 is destroyed by laser irradiation, it is possible to maintain an emission current larger than that of the prior art by setting the laser irradiation density to 8.6 MW / cm ² or less. That is, by setting the laser irradiation density to 0.7 to 8.6 MW / cm ² , it is possible to easily obtain better emission characteristics than the conventional technique in which the CNT 4 is exposed as it is.
[0024]
In the first embodiment, an excimer laser is used as the laser, but a YAG laser or a carbon dioxide gas laser may be used instead, or a frequency-modulated laser may be used instead of pulse irradiation. The laser irradiation method may be either a scanning method or a spot method, and the laser irradiation atmosphere is preferably in the air, but may be in a vacuum. When laser irradiation is performed in the atmosphere as in the first embodiment, there is an effect that the laser irradiation density can be reduced due to the influence of oxidation.
[0025]
In the first embodiment, the method for manufacturing a cold cathode electron source having a bipolar structure has been described. However, the present invention can also be applied to a cold cathode electron source having a three-pole structure. That is, as shown in FIG. 8, after laser irradiation to the electron emission portion 3, the gate structure 10 including the gate insulating film 11 and the gate electrode 12 is formed on the cathode electrode 2 so as to surround the electron emission portion 3, and thereafter In addition, a cold cathode electron source having a tripolar structure can be formed by disposing an anode electrode 9 facing the cathode electrode 2 at a predetermined distance.
[0026]
FIG. 9 is a plan view when the structure shown in FIG. 8 is viewed from above. As shown in FIGS. 8 and 9, a plurality of microcavities 13 arranged in a matrix are formed in the gate insulating film 11 and the gate electrode 12. The electron emission portions 3 are provided in one-to-one correspondence with the microcavities 13 and are arranged in a matrix on the cathode electrode 2. And the electron emission part 3 is located in the microcavity 13, and the electron discharge | released from CNT4 passes through the microcavity 13, and reaches the anode electrode 9. FIG. Such a structure is called a microcavity structure.
[0027]
Thus, the present invention can also be applied to a cold cathode electron source having a three-pole structure, and the emission characteristics of such a cold cathode electron source can be improved.
[0028]
Embodiment 2. FIG.
In the manufacturing method of the cold cathode electron source having the tripolar structure described in the first embodiment, the gate structure 10 is formed after the electron emission portion 3 is irradiated with the laser. You may perform laser irradiation with respect to the electron emission part 3 later. In the second embodiment, a cold cathode electron source having a three-pole structure in such a case will be described.
[0029]
10 to 18 are cross-sectional views showing the method of manufacturing the cold cathode electron source according to Embodiment 2 of the present invention in the order of steps. The cold cathode electron source according to the second embodiment is a tripolar electron source having a microcavity structure, and can be employed as an electron source of a display device such as an FED, for example. Below, with reference to FIGS. 10-18, the manufacturing method of the cold cathode electron source which concerns on this Embodiment 2 is demonstrated in detail.
[0030]
First, as shown in FIG. 10, the cathode electrode 2 is formed on the insulating substrate 1, and the conductive paste 6 is patterned on the cathode electrode 2 by screen printing.
[0031]
Next, the patterned conductive paste 6 is dried and fired under the same conditions as in the first embodiment. As a result, the organic solvent, binder and dispersant in the conductive paste 6 are almost lost, and a plurality of electron emission portions 3 including the CNTs 4 and the carbon impurities 5 are formed on the cathode electrode 2 as shown in FIG. It is formed in a shape. At this time, most of the CNTs 4 in the electron emission portion 3 are buried in the carbon impurities 5. The electron emission unit 3 includes not only the standing CNT 4 but also the lying CNT 4.
[0032]
Next, as shown in FIG. 12, a gate insulating film material 21 is formed on the cathode electrode 2 so as to cover the electron emission portion 3, and thereafter, as shown in FIG. 13, the gate electrode material is formed on the gate insulating film material 21. 22 is formed. The gate insulating film material 21 is an insulating film having a thickness of 4 to 10 μm, and is formed by using, for example, a spin coat method in the second embodiment. The gate insulating film material 21 is made of, for example, silicon oxide glass or PPSQ (Polyphenylsilsesquioxane). The gate electrode material 22 is an aluminum film having a thickness of about 250 nm, for example. In the second embodiment, the gate electrode material 22 is formed by using, for example, an evaporation method.
[0033]
Next, as shown in FIG. 14, a resist 25 having a predetermined opening pattern is formed on the gate electrode material 22, and the gate electrode material 22 is wet-etched using the resist 25 as a mask. As a result, the gate electrode material 22 above the electron emission portion 3 is removed, the gate insulating film material 21 is partially exposed, and the gate electrode 12 is formed. Thereafter, the resist 25 is removed.
[0034]
Next, as shown in FIG. 15, dry etching is performed on the gate insulating film material 21 using the gate electrode 12 as a mask. The dry etching at this time is performed for 40 to 50 minutes using a gas in which CF ₄ and O ₂ are mixed at a ratio of 100: 25. Thereby, as shown in FIG. 16, the electron emission portion 3 is exposed, and the gate insulating film 11 is formed on the cathode electrode 2.
[0035]
At this time, since the thickness of the gate insulating film material 21 is not completely uniform, over-etching is performed on the gate insulating film material 21 in order to reliably expose the electron emission portion 3. Therefore, dry etching is performed also on the electron emission portion 3, and the carbon impurities 5 are partially removed as shown in FIG. The broken line in FIG. 16 indicates the shape of the carbon impurity 5 before dry etching. In addition, the electron emission portion 3 below the thinnest portion of the gate insulating film material 21 is dry-etched for about 10 minutes.
[0036]
In this way, a gate structure 10 composed of the gate insulating film 11 and the gate electrode 12 and surrounding each electron emission portion 3 is formed on the cathode electrode 2.
[0037]
As described in the first embodiment, the gate insulating film 11 and the gate electrode 12 are formed with a plurality of microcavities 13 arranged in a matrix by the etching. The electron emission unit 3 is located in the microcavity 13, and the plan view when the structure shown in FIG. 16 is viewed from above is the same as the plan view of FIG. Then, the electrons emitted from each CNT 4 of the electron emission unit 3 pass through the microcavity 13 and reach the anode electrode 9 described later.
[0038]
Next, as shown in FIG. 17, the tip of the CNT 4 buried in the carbon impurity 5 by irradiating the electron emission part 3 with laser from above in the atmosphere to partially remove the carbon impurity 5. To expose. Then, as shown in FIG. 18, the anode electrode 9 facing the cathode electrode 2 at a predetermined distance is disposed, and a field emission type three-pole cold cathode electron source is completed. In the second embodiment, the distance between the cathode electrode 2 and the anode electrode 9 is set to 550 μm, for example.
[0039]
As described above, in the manufacturing method of the cold cathode electron source according to the second embodiment, after the gate structure 10 surrounding the electron emission portion 3 is formed, the electron emission portion 3 is irradiated with laser. Heat generated by such laser irradiation is likely to be accumulated. Therefore, the CNT that was in the lying state before the laser irradiation can be erected with a laser having an irradiation density lower than that of the first embodiment. As a result, the emission characteristics of the cold cathode electron source can be improved while reducing damage to the gate structure 10 due to laser irradiation.
[0040]
In the second embodiment, dry etching is performed on the electron emission unit 3 before performing laser irradiation on the electron emission unit 3. Therefore, since the carbon impurity 5 is partially etched before the laser irradiation, the CNTs 4 are easily exposed during the laser irradiation. As a result, the CNT 4 is easily irradiated with a laser, and the CNT 4 is likely to be thermally deformed. Accordingly, the CNT 4 can be erected with a laser irradiation density lower than that of the first embodiment, that is, with a laser irradiation density lower than 0.7 MW / cm ² . As a result, it is possible to improve the emission characteristics of the cold cathode electron source while reducing damage to the gate structure 10 due to laser irradiation.
[0041]
In addition, the gate insulating film material 21 is etched to expose the electron emission portion 3, and the electron emission portion 3 is also etched, so that the step of forming the gate insulating film 11 and the electron emission portion 3 are Etching can be performed simultaneously. Therefore, a cold cathode electron source with good emission characteristics can be manufactured with fewer steps.
[0042]
Although not provided in the second embodiment, a laser-resistant film made of, for example, gold is formed on the gate electrode 12 before laser irradiation, thereby reducing damage to the gate structure 10 due to laser irradiation. Also good.
[0043]
Embodiment 3 FIG.
In the manufacturing method according to the second embodiment described above, the etching of the electron emission portion 3 is performed during the overetching of the gate insulating film material 21. Therefore, if the etching time is not properly adjusted, a part of the electron emission portion 3 is formed. The exposure time may not be exposed, or the electron emission part 3 may be excessively etched and the CNT 4 may be lost, so that the etching time management is not easy.
[0044]
Therefore, the third embodiment provides a manufacturing method with simpler process management than the manufacturing method according to the second embodiment.
[0045]
19-22 is sectional drawing which shows the manufacturing method of the cold cathode electron source which concerns on Embodiment 3 of this invention in order of a process. The cold cathode electron source according to the third embodiment is a three-pole electron source having a microcavity structure as in the second embodiment, and may be employed as an electron source of a display device such as an FED. it can. Below, with reference to FIGS. 19-22, the manufacturing method of the cold cathode electron source which concerns on this Embodiment 3 is demonstrated in detail.
[0046]
First, the structure shown in FIG. 11 is obtained using the manufacturing method described in the second embodiment. Then, as shown in FIG. 19, dry etching is performed on the electron emission portion 3. At this time, etching is performed for about 10 minutes at an etching power of 170 W using a gas in which CF ₄ and O ₂ are mixed at a ratio of 100: 25. Thereby, the carbon impurity 5 in the electron emission part 3 is partially removed, and the CNTs 4 are easily exposed during laser irradiation. 19 and FIGS. 20 and 21 described later indicate the shape of the carbon impurity 5 before etching.
[0047]
Next, as shown in FIG. 20, the gate insulating film 11 having a plurality of through holes 13 a that become a part of the microcavity 13 is formed on the cathode electrode 2 by screen printing. Specifically, a mask for screen printing is arranged above the cathode electrode 2 and the electron emission portion 3, and a paste-like gate insulating film material is placed between the mask and the squeegee to move the squeegee. Thus, the gate insulating film material is deposited on the cathode electrode 2 through the hole provided in the mask. As a result, a printed pattern is formed on the cathode electrode 2, and the gate insulating film 11 having a plurality of through holes 13a is formed. Each electron emission portion 3 is located inside the through hole 13 a and is surrounded by the gate insulating film 11.
[0048]
Next, as shown in FIG. 21, the gate electrode 12 having a plurality of through holes 13 b that become a part of the microcavity 13 is formed on the gate insulating film 11 using a mask vapor deposition method. Specifically, when a metal mask having a predetermined opening pattern is provided on the gate insulating film 11 and a crucible having a gate electrode material therein is heated by a heater, the gate electrode material is evaporated and provided on the metal mask. It adheres on the gate insulating film 11 through the hole. As a result, the gate electrode 12 having a plurality of through holes 13 b is formed on the gate insulating film 11. Note that the through hole 13 b of the gate electrode 12 communicates with the through hole 13 a of the gate insulating film 11.
[0049]
As described above, the gate structure 10 having a plurality of microcavities 13 including the through holes 13 a and 13 b is completed on the cathode electrode 2, and each electron emission portion 3 is surrounded by the gate structure 10. The plan view of the structure shown in FIG. 21 as viewed from above is the same as the plan view of FIG. 9 described above.
[0050]
Next, as shown in FIG. 22, the tip of the CNT 4 buried in the carbon impurity 5 by partially irradiating the carbon impurity 5 by irradiating the electron emission unit 3 with a laser from above in the atmosphere. To expose. Then, an anode electrode 9 (not shown) facing the cathode electrode 2 at a predetermined distance is disposed, and a field emission type tripolar cold cathode electron source is completed.
[0051]
Thus, in the manufacturing method of the cold cathode electron source according to the third embodiment, unlike the second embodiment, the gate structure 10 is formed using the screen printing method and the mask vapor deposition method. The electron emission portion 3 is not etched when the gate structure 10 is formed. Further, the electron emission portion 3 is etched in a step different from the step of forming the gate structure 10. Therefore, strict etching time management becomes unnecessary, and the process management becomes easier than the manufacturing method according to the second embodiment while improving the emission characteristics of the cold cathode electron source.
[0052]
【The invention's effect】
According to the method for manufacturing a cold cathode electron source according to the present invention, after the gate structure surrounding the electron emitting portion is formed, the electron emitting portion is irradiated with laser, and thus heat generated by the laser irradiation is likely to be trapped. . Therefore, it is possible to stand up the CNT in a lying state before the laser irradiation with a laser having a low irradiation density. As a result, with laser of low energy, without damaging the gate structure, Ru can improve the emission characteristic of a cold electron source.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a method of manufacturing a cold cathode electron source according to Embodiment 1 of the present invention in the order of steps.
FIG. 2 is a cross-sectional view showing a method of manufacturing a cold cathode electron source according to Embodiment 1 of the present invention in the order of steps.
3 is a cross-sectional view showing a method of manufacturing a cold cathode electron source according to Embodiment 1 of the present invention in the order of steps. FIG.
FIG. 4 is a cross-sectional view showing a method of manufacturing a cold cathode electron source according to Embodiment 1 of the present invention in the order of steps.
FIG. 5 is a cross-sectional view showing the method of manufacturing the cold cathode electron source according to Embodiment 1 of the present invention in the order of steps.
6 is a cross-sectional view showing the method of manufacturing the cold cathode electron source according to Embodiment 1 of the present invention in the order of steps. FIG.
7 is a cross-sectional view showing the method of manufacturing the cold cathode electron source according to Embodiment 1 of the present invention in the order of steps. FIG.
FIG. 8 is a cross-sectional view showing a modification of the method for manufacturing a cold cathode electron source according to Embodiment 1 of the present invention.
FIG. 9 is a cross-sectional view showing a modification of the method for manufacturing a cold cathode electron source according to the first embodiment of the present invention.
FIG. 10 is a cross-sectional view showing a method of manufacturing a cold cathode electron source according to Embodiment 2 of the present invention in the order of steps.
FIG. 11 is a cross-sectional view showing a method of manufacturing a cold cathode electron source according to Embodiment 2 of the present invention in the order of steps.
FIG. 12 is a cross-sectional view showing a method of manufacturing a cold cathode electron source according to Embodiment 2 of the present invention in the order of steps.
FIG. 13 is a cross-sectional view showing a method of manufacturing a cold cathode electron source according to Embodiment 2 of the present invention in the order of steps.
14 is a cross-sectional view showing a method of manufacturing a cold cathode electron source according to Embodiment 2 of the present invention in the order of steps. FIG.
FIG. 15 is a cross-sectional view showing a method of manufacturing a cold cathode electron source according to Embodiment 2 of the present invention in the order of steps.
FIG. 16 is a cross-sectional view showing a method of manufacturing a cold cathode electron source according to Embodiment 2 of the present invention in the order of steps.
17 is a cross-sectional view showing the method of manufacturing the cold cathode electron source according to Embodiment 2 of the present invention in the order of steps. FIG.
FIG. 18 is a cross-sectional view showing a method of manufacturing a cold cathode electron source according to Embodiment 2 of the present invention in the order of steps.
FIG. 19 is a cross-sectional view showing a method of manufacturing a cold cathode electron source according to Embodiment 3 of the present invention in the order of steps.
20 is a cross-sectional view showing the method of manufacturing the cold cathode electron source according to Embodiment 3 of the present invention in the order of steps. FIG.
FIG. 21 is a cross-sectional view showing the method of manufacturing the cold cathode electron source according to Embodiment 3 of the present invention in the order of steps.
22 is a cross-sectional view showing the method of manufacturing the cold cathode electron source according to Embodiment 3 of the present invention in the order of steps. FIG.
[Explanation of symbols]
2 cathode substrate, 3 electron emission part, 4 carbon nanotube, 5 carbon impurity, 8 laser, 10 gate structure, 11 gate insulating film, 12 gate electrode, 21 gate insulating film material, 22 gate electrode material.

Claims (3)

A method of manufacturing a cold cathode electron source comprising a carbon nanotube that emits electrons and an electron emission portion containing carbon impurities,
(A) forming a cathode electrode;
(B) forming the electron emission portion on the cathode electrode;
(C) forming a gate structure surrounding the electron emission portion on the cathode electrode;
(D) performing dry etching on the electron emission portion to expose the carbon nanotubes buried in the carbon impurities from the carbon impurities;
( E ) After the steps (c) and (d) , the electron emission portion is irradiated with a laser with an irradiation density smaller than 0.7 MW / cm ² , and the carbon nanotubes buried in the carbon impurities are And a step of further exposing the carbon impurities. The gate structure includes a gate insulating film and a gate electrode,
The step (c)
(C-1) forming a gate insulating film material on the cathode electrode so as to cover the electron emission portion;
(C-2) forming a gate electrode material on the gate insulating film material;
(C-3) removing the gate electrode material above the electron emission portion to form the gate electrode;
(C-4) performing the dry etching on the gate insulating film material exposed in the step (c-3) to expose the electron emission portion and forming the gate insulating film;
Including
The said process (d) is a manufacturing method of the cold cathode electron source of Claim 1 performed when the said electron emission part is exposed in the said process (c-4) . The gate structure includes a gate insulating film and a gate electrode,
The step (c)
(C-1) forming the gate insulating film on the cathode electrode using a printing method ;
(C-2) forming the gate electrode on the gate insulating film using a vapor deposition method ;
Including, manufacturing method of a cold cathode electron source according to claim 1.

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