JP2000248395A - Method for controlling electrodeposition and production of quantum magnetic disk and electron emitting element using the method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrodeposition controlling method for monitoring the position at the objective place and stopping electrodeposition. SOLUTION: The electrode 1 to be electrodeposited, a counter electrode 2 and a reference electrode 3 are connected to a potentiostat 4, and a monitor electrode 5 is connected to a power source 7 via an ammeter or a voltmeter 6. Electrodeposition is executed in such a manner that the potential of the monitor electrode 5 viewed from the reference electrode 3 is set to be baser than the oxidation-reduction potential and nobler than the electrode 1 to be electrodeposited, and at the instant in which an electrodeposit 13 comes into contact with the monitor electrode 5, a measuring instrument 6 detects the change of the electric current value or voltage caused by the potential difference between the electrode 1 to be electrodeposited and the monitor electrode 5, a personal computer 9 allows the potentiostat 4 and the power source 7 to stop the potential feed, and the electrodeposition is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to
Regarding a control method when it is necessary to control an electrodeposit at a desired position, in particular, a lower electrode, an insulating layer having pores and an upper electrode are laminated in this order on a substrate, and electrodeposited in the pores. The present invention relates to a method for manufacturing an electron-emitting device or a quantum magnetic disk in which electrodes are buried by the method.

[0002]

2. Description of the Related Art Electrodeposits are conventionally controlled by calculating current efficiency, calculating the amount of deposition from Faraday's law, and controlling the amount of Coulomb by time or current. The current efficiency changes depending on the temperature, the liquid PH, the shape of the portion to be electrodeposited, the total area of the electrodeposition, the electrodeposition current, and the like. Further, in order to obtain the current efficiency, the volume to be deposited must be known, but it is difficult to accurately determine the volume when the portion to be deposited has a complicated shape.

As a method of measuring the thickness of an electrodeposit in an electrolytic solution, an ultrasonic pulse is incident on the electrodeposit and the reflected wave on the surface of the electrodeposit and the reflected wave on the metal surface of the electrodeposited substrate are measured. There is a method of knowing the film thickness of the electrodeposit with the time delay of the above. However, in this method, the measurable time delay is almost the same as the width of the ultrasonic pulse, so that it was difficult to measure the thickness of a thin film compared to the wavelength of the ultrasonic wave.

Therefore, as a method of measuring the thickness of a thin film as compared with the wavelength of the ultrasonic wave, the angle of incidence of the ultrasonic wave incident on the substrate from the ultrasonic wave propagating liquid is unique to the substrate, the liquid and the material of the film. When the ratio of the wavelength of the ultrasonic wave (λ) to the film thickness is a value specific to the substrate, the liquid and the substance of the film, the reflectivity of the ultrasonic wave is reduced, and the film thickness is reduced. There is a technology to measure. However, in this measurement method, the ratio of the incident angle and the wavelength of the ultrasonic wave to the film thickness depends on the material of the substrate, liquid and film. The disadvantage is that these values need to be checked each time they change.

[0005] JP-A-09-269216 reports that a thin film thickness can be measured by a simple method. This is a surface reflected wave reflected on the film surface of a burst wave transmitted to the film by changing the frequency as appropriate (referred to as an ultrasonic wave that suddenly rises and goes through a flat portion and then disappears rapidly). And a composite wave of a boundary reflected wave reflected at an interface between the film and the solid substrate. The envelope of each extreme value in either the positive or negative direction of the composite wave becomes flat, and at least two frequencies of the burst wave substantially corresponding to any state change such as the most protruding or the most depressed are obtained. The following formula is used to determine the film thickness d.

D = v × M / (2 × (f2−f1)) where v is the sound velocity of the material constituting the film, and M is the position obtained by dividing the phase difference corresponding to the change in the state of the envelope by 2π. Phase difference wave number,
f2 and f1 are the frequencies of the burst waves substantially corresponding to the state changes such as the most protruding or the most depressed, respectively.

[0007] Japanese Patent Application Laid-Open No. 6-88295 reports a method of monitoring and controlling the film thickness of an electrodeposit during ultrasonic deposition.

However, in the method of measuring the film thickness utilizing the speed of sound as described above, the limit of the film thickness that can be measured is on the order of μm, and the film thickness of a thinner deposit is detected during the electrodeposition. It is difficult to control.

[0009]

Heretofore, in the case of controlling an electrodeposit to a thin film thickness, a blind control method using time or current has been used to obtain current efficiency. In addition, since the amount of electrodeposition fluctuates depending on a slight change in the electrodeposition conditions, it has been difficult to accurately stop the electrodeposition at a target position.
For this reason, in a structure in which a lower electrode, an insulating layer having pores, and an upper electrode are stacked in this order on a substrate, the embedding of the deposits in the pores is particularly controlled, and the electron-emitting device is used. Was very difficult to produce.

Therefore, in the present invention, regardless of the change in the amount of electrodeposition depending on the shape, total area, electrodeposition current, etc. of the portion where the electrodeposition is performed, and irrespective of the electrodeposit and the underlying metal material, To provide an electrodeposition control method that stops the electrodeposition by monitoring the position, not the film thickness, of the electrodeposit at the place to be deposited, and also provides a method of manufacturing an electron-emitting device or a quantum magnetic disk using this method. The purpose is to do.

[0011]

According to a first aspect of the present invention, a monitor electrode controls the electrodeposition in an electrolytic solution in addition to an electrode to be deposited, a counter electrode, and a reference electrode. An ammeter or a voltmeter is connected to the monitor electrode, and the potential of the monitor electrode with respect to the reference electrode is lower than the oxidation-reduction potential of oxygen generation.
Electrodeposition is performed by setting the potential to be nobler than the potential of the electrode to be deposited, and at the moment the electrodeposit contacts the monitor electrode, the current value due to the potential difference between the electrode to be deposited and the monitor electrode is determined. This is a method for controlling electrodeposition, in which a control device detects a change or a change in a voltage value and stops electrodeposition.

A second invention is characterized in that, in the first invention, the potential of the monitor electrode with respect to the reference electrode is set to be more noble than the oxidation-reduction potential of the deposit.

According to a third aspect of the present invention, in the first or second aspect, the electrode to be deposited and the monitor electrode are arranged on the same plane on an insulating substrate.

According to a fourth aspect of the present invention, in the first or second aspect, the monitor electrode is provided in contact with a peripheral portion of the hole in the laminated structure of the electrode to be deposited and the insulating layer having the hole on the substrate. It is characterized by having been done.

According to a fifth aspect of the present invention, in the method for controlling electrodeposition according to the fourth aspect, when a large number of the holes exist, a monitor electrode is provided in at least one of the holes.

According to a sixth aspect of the present invention, in the electrodeposition control method according to the fourth or fifth aspect, a monitor electrode is provided at a certain distance from a peripheral portion of the hole.

According to a seventh aspect, in any one of the first to sixth aspects, the method further comprises a step of removing the monitor electrode after the electrodeposition control.

According to an eighth aspect of the present invention, in the method for controlling electrodeposition according to any one of the fourth to seventh aspects, the holes are formed by photolithography and have a diameter of about several μm.

According to a ninth aspect of the present invention, in the method for controlling electrodeposition according to any one of the fourth to seventh aspects, the pores are formed by anodic oxidation of aluminum and have a pore diameter of about several tens nm. .

A tenth aspect of the present invention uses the electrodeposition control method according to the fourth aspect of the present invention in which a lower electrode, an insulating layer, and an upper electrode are sequentially stacked on a substrate, and the upper electrode is a monitor electrode. A method for manufacturing a quantum magnetic disk (QMD), characterized in that a monitor electrode is removed after electrodeposition control, and an electrodeposit is buried in a hole of an insulating layer.

According to an eleventh aspect of the present invention, there is provided a method for controlling electrodeposition according to the fourth or fifth aspect, wherein the lower electrode, the insulating layer, and the upper electrode are sequentially stacked on the substrate, and the upper electrode is used as a monitor electrode. This is a method for producing an electron-emitting device having a small gap between an upper electrode and an electrodeposit, produced by the method described above.

According to a twelfth aspect, in the eleventh aspect,
The hole is formed by photolithography and has a hole diameter of about several μm.

According to a thirteenth aspect, in the eleventh aspect,
The hole is formed by anodizing aluminum and has a hole diameter of about several tens nm.

[0024]

[First Embodiment] An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing the most basic configuration of the present invention. FIG.
In FIG. 1A, reference numeral 1 denotes an electrode to be deposited, 2 denotes a counter electrode, and 3 denotes a reference electrode, which is connected to a potentiostat 4. Reference numeral 5 denotes a monitor electrode, which is supplied with a power through an ammeter or a voltmeter 6.
Connected to 7. The monitor electrode 5 is connected to the reference electrode 3 via another voltmeter 8. The potentiostat 4 and the power supply 7 are controlled by a personal computer 9. The electrode 1 to be deposited and the monitor electrode 5 are electrically insulated by an insulating layer 10. Reference numeral 11 denotes an electrolytic cell, and 12 denotes an electrolytic solution. FIG.
In the arrangement of the monitor electrodes as shown in (b), the potential of the monitor electrode 5 viewed from the reference electrode 3 is set so as to be lower than the oxidation-reduction potential of oxygen generation and more noble than the electrode 1 to be electrodeposited. When the electrodeposit 13 is in contact with the monitor electrode 5, the measuring instrument 6 detects a change in current value or a change in voltage due to a potential difference between the electrode to be deposited 1 and the monitor electrode 5, and the personal instrument The computer 9 stops supplying the potential to the potentiostat 4 and the power supply 7 to stop the electrodeposition. Here, in order to keep the current flowing between the electrode to be deposited 1 and the monitor electrode 5 via the liquid resistance small, it is preferable that the potential difference between the two electrodes is small. In addition, when an electrodeposit is deposited on the monitor electrode 5 to cause a problem (for example, when it is necessary to selectively remove the monitor electrode 5 later).
Is added to the condition that the potential of the monitor electrode 5 is more noble than the oxidation-reduction potential of the deposit.

[Second Embodiment] Next, an example in which the arrangement positions of the monitor electrodes are different from those of the first embodiment will be described. FIG. 2 shows a case where an electrode to be deposited and a monitor electrode are arranged on the same plane on an insulating substrate. 21 is an electrode on which electrodeposition is performed, 22 is an insulating substrate, and 23 is a monitor electrode. Electrodeposition is started, and an electrodeposit 24 grows on the substrate 22 to monitor the electrode 23.
The electrodeposition stops in the same place as in the first embodiment. The distance between the electrode 21 to be deposited and the monitor electrode 23 is
Area can be defined. The monitor electrode 23 can be removed by selective etching after electrodeposition. For example, the electrode 21 to be deposited, the insulating substrate 22, the monitor electrode 23, and the electrodeposit 24 are made of Au, SiO ₂ , Pt, and Ni, respectively.
When CrO ₃ + H ₂ SO ₄ is used as an etchant, only the monitor electrode can be removed.

[Embodiment 3] FIG. 3 shows a case where the above-mentioned monitor electrode is provided in contact with a peripheral portion of a hole in a laminated structure of an electrode to be deposited and an insulating layer having a hole on a substrate. 31 is an electrode to be deposited, 32 is an insulating layer having at least one hole, 33 is a monitor electrode, and 35 is a substrate. The monitor electrode 33 is installed on the substrate 35 by vacuum evaporation,
The electrode 31 to be deposited, the insulating layer 32, the monitor electrode 33 and a mask material (not shown) are laminated in this order by spin coating or the like, a hole pattern is formed by photolithography or anodic oxidation, and holes are formed by dry etching or the like. It can be performed by a method of exposing the electrode 31 or the like. The mask material is removed before or after electrodeposition as required. This control method can be applied regardless of the size and shape of the hole. Electrodeposit 34 deposited on electrode 31 to be deposited in the hole
However, when reaching the boundary portion between the insulating layer 32 and the monitor electrode 33, the deposition stops as in the first embodiment. That is, the height of the electrodeposit 34 can be defined by the thickness of the insulating layer. Here, when there are many holes, the monitor electrode 33 only needs to be provided for at least one hole. When the insulating layer is removed after the control, a columnar electrodeposit is obtained.

[Embodiment 4] FIG. 4 shows a case where a monitor electrode is placed at a certain distance from the periphery of a hole in a laminated structure of an electrode to be deposited and an insulating layer having a hole on a substrate. is there. 41 is an electrode to be deposited, 42 is an insulating layer having at least one hole, 43 is a monitor electrode, and 45 is a substrate. The monitor electrode 43 is provided by stacking the electrode 41 to be deposited, the insulating layer 42, and a mask material (not shown) in this order on the substrate 45 by vacuum evaporation, spin coating, or the like, and forming a mask pattern by photolithography to form the monitor electrode 43. Mask evaporation is performed. After lifting off the mask material,
The method can be performed by applying a mask material again, forming a hole pattern by photolithography or an electron beam, and exposing the electrode 41 to be deposited by making holes by dry etching or the like. The mask material is removed before or after electrodeposition as required. When electrodeposition is performed, an electrodeposit 44 deposited on the electrode 41 to be deposited
2 begins to form a spherical surface, and the deposit 44
Electrodeposition is stopped in the same manner as in the form 1 at the place where it contacts with No. 3. The diameter of the sphere can be defined by the distance from the periphery of the hole to the monitor electrode 43.

[0028]

The present invention will be described in more detail with reference to the following examples.

[Example 1] As Example 1, the structure of FIG.
An example of controlling the film thickness of electrodeposition will be described.

(Step 1) A monitor electrode is arranged on the electrode to be deposited. As shown in FIG. 1B, an insulating layer 10 and a monitor electrode 5 are laminated in order on a part of the electrode 1 to be deposited by sputtering. did.
The composition is electrodeposited electrode Au, insulating layer SiO ₂ : 200 nm,
Monitor electrode Pt: 30 nm. A metal other than Au or a low-resistance compound can be used for the electrode 1 to be deposited, and a chemically stable noble metal such as Pt or Pd is preferably used. The insulating layer 10 may be made of any material other than SiO ₂ as long as the material has an insulating surface and does not leak between the electrodes. Metal other than Pt can be used for the monitor electrode 5.

(Step 2) Electrodeposition As an electrodeposit, N is commonly used as an electrodeposition material.
i, and the composition of the electrolyte is NiSO ₄ : 1 × 10 ⁻¹ m
ol / l, H ₃ BO ₄ : 3 × 10 ^-1 mol / l aqueous solution
H = 4.1, and the most basic Ni electrolyte was used. A carbon electrode, which is an inert electrode, was used as a counter electrode, and Ag / AgCl was used as a reference electrode. In order to selectively deposit only Au, the potential of the monitor electrode viewed from the reference electrode is changed to the oxidation-reduction potential of Ni (−0.4 V vs. A).
g / AgCl) and the redox potential of H ² (−0.2 V vs. Ag / AgC) so that hydrogen generation does not occur.
l) is set to 0V which is more noble than A).
Ni was deposited on u. At the moment when the Ni deposited on Au came into contact with the monitor electrode, an increase in the current value due to the disappearance of the liquid resistance was observed, and the electrodeposition was stopped. The thickness of the Ni electrodeposited film is 200 n, which is the distance between the electrode to be deposited and the monitor electrode.
m. Since this distance was the thickness of the insulating layer, it could be easily set.

Example 2 As Example 2, an example of manufacturing a quantum magnetic disk (QMD) with the monitor electrode arrangement of FIG. 3 described in the above embodiment will be described with reference to FIG.

(Step 1) Deposition of Thin Film on Si Substrate On the Si substrate 55, the electrode 51 (A
u: 50 nm), an insulating layer 52 (SiO ₂ : 200 nm), and a monitor electrode 53 (Pt: 50 nm) in this order. Further, PMMA 56 (polymet) is placed on the monitor electrode 53.
hy-methacrylate) was applied. FIG.
(A) shows the laminated structure.

(Step 2) Formation of Pore A hole pattern is formed in PMMA (56) by electron beam lithography, and Pt (53) is etched with H ₂ SO _4. ) Is formed. Subsequently, CF ₄ is used with the monitor electrode 53 as a mask.
The insulating layer SiO ₂ (52) was etched with a gas to expose the electrode to be electrodeposited Au (51). FIG. 5B shows a state in which the pores are formed.

(Step 3) Electrodeposition into pores A carbon electrode, which is an inert electrode, is used as a counter electrode, and Ag / AgCl is used as a reference electrode. The composition of the electrolytic solution is NiSO ₄ : 1 ×
_{^{10 -1 mol / l, H 3}} BO 4: was performed electrodeposition in an aqueous solution of ^{3 × 10 -1 mol / l (} PH = 4.1). In order to selectively deposit only Au (51), the potential of the monitor electrode 53 viewed from the reference electrode is changed to the oxidation-reduction potential of Ni (−
0.4 V vs. Ag / AgCl) and the oxidation-reduction potential of H2 (-0.2 V
vs. Ag / AgCl), and Ni was deposited in the pores at a constant voltage of -0.8 V. Ni (54) deposited on the electrode Au (51) to be deposited is
Electrodeposition was stopped at the point where the interface between the insulating layer 3 and the insulating layer 52 was reached.
FIG. 5C shows a state in which the electrodeposition is performed in the pores.

(Step 4) Removal of Monitor Electrode The monitor electrode 53 (Pt) was selectively etched with CrO ₃ + H ₂ SO ₄ to produce a QMD. FIG.
(D) is the completed drawing.

Example 3 As Example 3, an example in which an electron-emitting device was manufactured with the monitor electrode arrangement of FIG. 3 described in the above embodiment will be described with reference to FIG.

(Step 1) Formation of lower electrode, insulating layer having pores and upper electrode On a glass substrate 65, a lower electrode 61 (T
a: 300 nm), insulating layer 62 (SiO ₂ : 100 n)
m) and the upper electrode 63 (Pt: 20 nm). For the lower electrode, a metal other than Ta or a low-resistance compound can be used, and metals such as Mo, W, and Pt are preferably used because of their high thermal stability. The insulating layer SiO ₂ is a material having a small dielectric constant and a high withstand voltage. The upper electrode may be made of the same material as the lower electrode, but since it is used as a monitor electrode in a later step, the oxidation-reduction potential is noble and Pt, which is an inert metal, was selected.

Next, a resist (not shown) is applied on the upper electrode by spin coating, a hole pattern (circle having a diameter of 2 μm) is formed by photolithography, and Pt (63) is applied by Ar plasma, followed by CF ₄ gas. The lower electrode 61 was exposed by etching SiO ₂ (62). FIG. 6A is a configuration diagram of these.

(Step 2) Electrodeposition into the hole A carbon electrode which is an inert electrode at the counter electrode, and A is a reference electrode
Using g / AgCl, electrodeposition was performed on the lower electrode 61 in the pores using the upper electrode 63 as a monitor electrode. Electrodeposit 6
4 is a high melting point material such as Mo, W, etc., because it becomes an electron emitter. Ni, which is generally widely used as an electrodeposition material, is used. The composition of the electrolyte is NiSO ₄ : 1 × 10
^-1 mol / l, H ₃ BO ₄ : 3 × 10 ^-1 mol / l aqueous solution
(PH = 4.1). In order to selectively deposit only on the lower electrode 61, the potential of the monitor electrode 63 viewed from the reference electrode is changed to the oxidation-reduction potential of Ni (−0.4 V vs.
Ag / AgCl) and a redox potential (−0.2 V vs. Ag / Ag) of H ₂ so that hydrogen generation does not occur.
Cl), the potential of the lower electrode 61 is set to 0 V, which is more noble than Cl).
1.0V vs. Ag / AgCl) -1.1
V was set. When electrodeposition is performed under these conditions,
Electrodeposition was stopped when Ni (64) deposited on the lower electrode 61 reached the interface between the upper electrode 63 and the insulating layer 62. FIG.
(B) is a state in which the electrodeposit is embedded in the hole.

(Step 3) Preparation of a minute gap between the electrodeposit and the upper electrode The electrodeposit 64 and the upper electrode 6 buried in the hole in the step 2
Since the contact point with No. 3 is very small, when a voltage is applied between the upper and lower electrodes to flow a current, forming due to Joule heat occurs at the contact point. As a result, a small gap of several nanometers serving as an electron emitting portion was formed between the electrodeposit and the upper electrode, and an electron emitting device was manufactured. FIG. 6C is a completed view of the electron-emitting device. Electron emission from the electron emitting portion 66 was confirmed by placing the electron-emitting device manufactured in this example in a vacuum apparatus and applying a voltage with the lower electrode being negative and the upper electrode being positive.

[0042]

As described above, according to the electrodeposition control method of the present invention, the electrodeposition is controlled by monitoring not the film thickness but the position, and the shape of the portion where the electrodeposition is performed
Irrespective of changes in the amount of electrodeposition depending on the total area, the electrodeposition current, etc., the electrodeposition can be accurately controlled at the installation position of the monitor electrode. According to the present invention, in a structure in which a lower electrode, an insulating layer having pores, and an upper electrode are stacked in this order, embedding of deposits in the pores is accurately controlled at the interface between the insulating layer and the upper electrode. As a result, an electron-emitting device or a quantum magnetic disk could be manufactured.

[Brief description of the drawings]

FIG. 1A is a schematic diagram showing a configuration of the present invention. FIG. 1B is a cross-sectional view for explaining the first embodiment.

FIG. 2 is a cross-sectional view illustrating a second embodiment.

FIG. 3 is a cross-sectional view for explaining a third embodiment.

FIG. 4 is a cross-sectional view for explaining a fourth embodiment.

5 is a cross-sectional view for explaining Example 2, FIG. 5 (a) is a state after thin film deposition, FIG. 5 (b) is a state after pore formation, FIG. 5 (c) Fig. 5 shows the state after electrodeposition control,
(D) shows a state where the QMD is completed.

6A and 6B are cross-sectional views for explaining Example 3; FIG. 6A is a state after forming pores, FIG. 6B is a state after forming buried electrodes, and FIG. ) Shows the completed state of the electron-emitting device.

[Explanation of symbols]

 1,21,41 Electrodeposited electrode 2 Counter electrode 3 Reference electrode 4 Potentiostat 5,23,33,43,53 Monitor electrode 6 Ammeter or voltmeter 7 Power supply 8 Voltmeter 9 Personal computer 10,22,32,42 , 52, 62 Insulating layer 11 Electrolyzer 12 Electrolyte 13, 24, 34, 44, 54 Electrodeposit 35, 45, 55, 65 Substrate 51 Electrodeposited electrode (wiring) 61 Lower electrode (wiring) 64 Electrodeposit (Embedded electrode) 66 Electron emission part

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinichi Kawate 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 4K058 AA02 BA17 BB02 FB02 FB04 5D112 AA18 AA24 EE06

Claims (13)

[Claims] 1. A monitor electrode is disposed in a portion of an electrolytic solution in which an electrode to be deposited, a counter electrode and a reference electrode are to be controlled, and an ammeter or a voltmeter is connected to the monitor electrode. The potential of the monitor electrode with respect to the reference electrode is set to be lower than the oxidation-reduction potential of oxygen generation, and is set to be more noble than the potential of the electrode to be deposited. At the moment of contact with the monitor electrode, a change in current value due to a potential difference between the electrode to be deposited and the monitor electrode, or
A method for controlling electrodeposition, comprising detecting a change in a voltage value and causing a control device to stop electrodeposition. 2. The method according to claim 1, wherein the potential of the monitor electrode with respect to the reference electrode is set to be more noble than the redox potential of the deposit. 3. The method according to claim 1, wherein the electrode to be deposited and the monitor electrode are arranged on the same plane on an insulating substrate. 4. The monitor electrode according to claim 1, wherein the monitor electrode is provided in contact with a peripheral portion of the hole in the laminated structure of the electrode to be deposited and the insulating layer having the hole on the substrate. Control method of electrodeposition. 5. The method for controlling electrodeposition according to claim 4, wherein when a large number of said holes are present, a monitor electrode is provided in at least one of said holes. 6. The method for controlling electrodeposition according to claim 4, wherein a monitor electrode is provided at a certain distance from a peripheral portion of the hole. 7. The method for controlling electrodeposition according to claim 1, further comprising a step of removing the monitor electrode after the electrodeposition control. 8. The method for controlling electrodeposition according to claim 4, wherein said holes are formed by photolithography and have a diameter of about several μm. 9. The method for controlling electrodeposition according to claim 4, wherein said holes are formed by anodic oxidation of aluminum and have a hole diameter of about several tens of nanometers. . 10. The method for controlling electrodeposition according to claim 4, wherein the upper electrode is a monitor electrode in a laminated structure of a lower electrode, an insulating layer, and an upper electrode on a substrate. A method for manufacturing a quantum magnetic disk (QMD), which comprises removing an electrode from a monitor and embedding an electrodeposit in a hole of an insulating layer. 11. A method for controlling electrodeposition according to claim 4, wherein the lower electrode, the insulating layer, and the upper electrode are sequentially stacked on the substrate, wherein the upper electrode is a monitor electrode. A method for manufacturing an electron-emitting device having a minute gap between an electrode and an electrodeposit. 12. The method according to claim 11, wherein the holes are formed by photolithography and have a hole diameter of about several μm. 13. The method for manufacturing an electron-emitting device according to claim 11, wherein said holes have a hole diameter of about several tens nm, which is formed by anodic oxidation of aluminum.