JP2003157760A - Manufacturing method of electron source and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of an image forming device in which the cross-sectional shape of the element is freely controlled without being affected by the disturbance factor and the conductive film of such a shape which enablers the formation of an excellent electron emitting part is formed, and thereby, the fluctuations of the element characteristics are small, and which is of low cost. SOLUTION: In the image forming device, the lump height of the liquid-drop which is jetted from the jet nozzle and adhered to the substrate is detected, and the deviation between the lump height and the target liquid-drop lump height is calculated to correct the deviation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron-emitting device, an electron source substrate, and a method and apparatus for manufacturing an image forming apparatus.

[0002]

2. Description of the Related Art The applicant of the present invention has disclosed a surface-conduction electron-emitting device as an inexpensive and simple manufacturing method.
At 50, a method for producing a surface conduction electron-emitting device by discharging a metal-containing solution in a droplet state onto a substrate to form a conductive thin film and a device electrode as shown in FIG. did.

In FIG. 5, 1 is a substrate, 2 and 3 are device electrodes, 4 is a conductive film, and 5 is an electron emitting portion. By applying a voltage to the device electrodes 2 and 3 to perform energization treatment, The electron emitting portion 5 is formed.

Further, an electron source substrate in which the above electron-emitting devices are arranged in a matrix on the substrate 1 and an image forming apparatus have been manufactured.

FIG. 3 is a schematic view showing an example of a conventional process of ejecting a metal-containing solution onto a substrate to form a conductive thin film and a device electrode.

In FIG. 3, an ejection head 7 is installed above the substrate 1 on a substrate stage 8, and the metal-containing solution is ejected in a droplet state from an ejection nozzle 9 provided in the ejection head 7. Then, it is attached on the substrate 1. Fig. 3
The reference numeral 2 is a droplet that has been ejected and then adhered to the substrate.

Thereafter, the conductive thin film is formed by firing or the like.

Here, the ejection head 7 is provided with an ink jet control / drive mechanism 16 to control the ejection of liquid droplets.

Further, the stage 8 is provided with a position detecting mechanism 17 and a stage driving mechanism (not shown) so that the stage can be moved in the X and Y directions, and discharge is performed in conjunction with the ink jet control / driving mechanism 16. The droplets are ejected from the head 7 to adhere the droplets onto the substrate.

The movement is not limited to the stage side,
The head side or both the head and the stage may be moved. Further, FIG. 3 shows an example in which the head is arranged above the substrate, but conversely, the head may be arranged below and ejected from below, or may be arranged laterally and ejected.

[0011]

However, in the conventional step of attaching the droplets to the substrate, the uneven shape of the droplets varies from substrate to substrate due to various disturbance factors, and as a result, the droplets are baked or the like. The resulting unevenness of the conductive thin film has a negative effect on the process of forming the electron-emitting portion due to energization of the conductive thin film, which causes variations in electron emission characteristics between substrates, resulting in poor yield. There was a problem of doing.

Therefore, an object of the present invention is to arbitrarily control the cross-sectional shape of the device without depending on the above-mentioned disturbance factors, and to form a conductive thin film having a shape in which a favorable electron-emitting portion is formed. (EN) Provided are an electron source which has low variation in temperature and can be easily manufactured at low cost, a manufacturing method thereof, an image forming apparatus having the electron source, and manufacturing methods thereof.

[0013]

SUMMARY OF THE INVENTION The above-mentioned object is to provide a method of manufacturing an electron source substrate, which comprises a step of ejecting droplets of a metal-containing solution to adhere them to the substrate, wherein the method of manufacturing the electron source substrate is at least While relatively moving at least one of the ejection head and the substrate by means for ejecting liquid droplets from a plurality of ejection nozzles provided in the ejection head and means for controlling the relative position of the ejection head and the substrate, In the step of adhering the droplets onto the substrate from the plurality of ejection nozzles, the protrusion of the droplets ejected from the ejection nozzles and adhering to the substrate is detected, and the measured protrusion and the target droplet or electron source. It is possible to solve the problem by calculating the deviation amount from the ridge and correcting the droplet shape based on the calculated deviation amount.

That is, the present invention provides the following (1) to (1)
2).

(1) A plurality of electron-emitting devices having an electron-emitting portion in a part of the conductive thin film and a conductive thin film for connecting a pair of device electrodes are arranged on a substrate, and the electron-emitting devices are arranged between the electron-emitting devices. A method for manufacturing an electron source substrate having wirings and voltage application terminals for the element, the method comprising:
At least one of the ejection head and the substrate is provided by at least a means for ejecting a droplet of a solution containing a metal element from an ejection nozzle provided in the ejection head and a means for controlling the relative position of the ejection head and the substrate. A step of adhering the droplet onto a substrate from an ejection nozzle provided in the ejection head while moving relatively, and a step of adhering the droplet onto the substrate is at least ejected from the ejection nozzle. The step of detecting the protrusion of the droplet that is adhered to the substrate, the step of calculating the deviation amount between the measured protrusion and the target protrusion of the droplet, and the droplet shape based on the calculated deviation amount. A method of manufacturing an electron source, comprising a step of correcting.

(2) The step of detecting the protrusion of the liquid droplets comprises
The method for producing an electron source according to (1), which is based on an optical image obtained by reflected light or transmitted light when the droplet is irradiated with light.

(3) The step of detecting the protrusion of the liquid droplets comprises
The method for producing an electron source according to (1) or (2), which is performed by a light intensity ratio signal of the optical image.

(4) The step of correcting the droplet shape is performed by controlling the temperature or humidity around the substrate at the time of applying the droplets (1) to (3).
The method for manufacturing an electron source according to.

(5) In the electron source according to (1) to (4), the step of correcting the shape of the droplet is performed by optimizing the composition of the solution containing the metal element. Production method.

(6) In the method of manufacturing an electron source according to any one of (1) to (3), the step of depositing the droplets on the substrate includes the step of applying the droplets to the same place a plurality of times in multiple layers. The method of manufacturing an electron source according to (1) to (3), wherein the step of correcting the droplet shape is performed by controlling a time interval of repeated application of the droplets.

(7) The method of manufacturing an electron source according to (1) to (6), wherein the ejection head is an ink jet system.

(8) Use of a plurality of ejection heads (1)
~ The method for manufacturing an electron source according to (7).

(9) The manufacturing method according to (1) to (8), wherein the ink jet system is a system in which bubbles are formed in the solution by thermal energy and the solution is ejected.

(10) The ink jet system is a system for ejecting a solution by mechanical energy (1).
~ The method for manufacturing an electron source according to (9).

(11) When the electron source substrate is formed,
Column-direction wirings and row-direction wirings are arranged in a matrix through an insulating layer, one of the pair of element electrodes is connected to the insulating substrate to form a column-direction wiring, and the other is connected via an insulating layer. The method for manufacturing an electron source according to (1) to (10), wherein the wiring is in the row direction.

(12) An electron-emitting device as an electron source,
Manufacture of an image forming apparatus including a voltage applying unit for the element, a light-emitting body that emits light by receiving electrons emitted from the element, and a drive circuit that controls a voltage applied to the element based on an external signal. A method comprising the steps of:
A method for manufacturing an image forming apparatus, characterized by being manufactured by the method according to any one of (11).

According to the present invention, when a conductive thin film which becomes an electron source is formed, a conductive thin film having a desired cross-sectional shape can be formed irrespective of various disturbance factors. In the process of forming the electron emitting portion by performing the energization process, formation defects of the electron emitting portion can be reduced, and as a result, an electron emitting source having good electron emitting characteristics can be produced with high yield.

[0028]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described below with reference to the drawings.

The flat surface conduction electron-emitting device will be described with reference to FIG.

FIG. 5 is a schematic plan view showing the basic structure of a flat surface conduction electron-emitting device according to an embodiment of the present invention.

In FIG. 5, 1 is a substrate, 2 and 3 are device electrodes, 4 is a conductive thin film, 5 is an electron emitting portion, 10 is a column-direction electrode, and 11 is a row-direction electrode. Is
It is disclosed in the above-mentioned Hei 08-171850.

FIG. 1 is a schematic view showing an example of a step of forming a conductive thin film by discharging a metal-containing solution onto a substrate in the manufacturing method of the present invention.

In FIG. 1, an ejection head 7 is installed above the substrate 1 on a substrate stage 8, and the metal-containing solution is ejected in a droplet state from an ejection nozzle 9 provided in the ejection head 7. Then, it is attached on the substrate 1. The number of discharge nozzles used for applying the droplets may be one or plural.

The ejection head 7 has an inkjet control
A drive mechanism 16 is provided, and the droplets are ejected in conjunction with a position detection mechanism 17 and a stage drive mechanism (not shown) provided on the stage 8 to attach the droplets to a target position on the substrate. You can

Further, an observing mechanism 13 is provided above the substrate for observing the raised state of the adhered droplets, and the light intensity distribution of the adhered droplets is controlled by the image processing device 14 based on the image from the observing mechanism 13. Is analyzed to measure the protrusion of the droplet and calculate the amount of deviation from the target cross-sectional shape of the conductive thin film. Then, based on the calculated shift amount, the inkjet control / drive mechanism 16, the position detection mechanism 17, the stage drive mechanism (not shown), and the environment control device (not shown) are controlled to correct the shift amount. You can The series of control is performed by the control computer 15.

The observation mechanism 13 is only required to be able to observe the adhered droplets, and examples thereof include a CCD camera.

The measurement and correction of the raised state of the adhered droplet will be described with reference to FIGS. 2 (a) to 2 (f).

The metal-containing solution ejected from the head retains the state of droplets without excessive aggregation / dispersion on the substrate due to the action of the film shape retainer contained in the solution, such as polyvinyl alcohol. . At this time, the cross-sectional shape of the droplet attached to the substrate, more specifically, the uneven shape is determined by the interaction of various conditions in the step of attaching the droplet to the substrate. The conditions include, for example, the surface state of the substrate, the solvent volatilization state in the droplet when the droplet adheres to the substrate, and the like. 2A to 2C are schematic views of the cross-sectional shape of the liquid droplets attached to the substrate. 2A shows a droplet having a convex central portion, FIG. 2B shows a flat droplet, and FIG. 2C shows a droplet having a concave central portion. Droplets attached to the substrate
2 (a) to 2 (c). By removing unnecessary solvent etc. by baking these droplets,
A conductive thin film can be formed. At this time, the cross-sectional shape of the conductive thin film is determined depending on the cross-sectional shape in the droplet state before the high temperature firing. That is, when the central portion is convex in the droplet state, as shown in FIG. 2D, the conductive film whose central portion is convex is flat in the droplet state as shown in FIG.
In the case where the flat conductive film as shown in (e) has a concave center in the droplet state, a conductive film having a concave center is formed as shown in FIG. 2 (f).

Therefore, by controlling the uneven shape of the droplets attached to the substrate, it is possible to form a conductive thin film having an arbitrary uneven shape. The process of actually controlling the uneven shape of the adhered droplets will be described below with reference to FIG.

(1) While scanning the stage 8 in the X direction of FIG. 1, the position detecting mechanism 17 and the inkjet control / driving mechanism 16 send an ejection signal to the nozzles of the ejection head 7 to eject the droplets. And then deposit it on the substrate. In this example, it is assumed that the droplets are applied to the same place at least twice more.

(2) Next, the observation system 13 and the image processing apparatus 1
4, the image of the droplet actually attached is captured, and the uneven shape of the droplet is measured from the light intensity distribution.

(3) The measured concavo-convex shape is compared with the target concavo-convex shape, and the droplet application conditions, for example, the time intervals of repeated ejection of the droplets are corrected so as to reduce the difference.

(4) Based on this correction condition, the above (1)-
By repeating (3), the uneven shape of the droplet is converged to a target value or an allowable range.

It should be noted that the unevenness measurement and correction of the adhered droplets can be performed within the image area of the electron source substrate or outside the image area.

Further, when the droplet is not applied to the same place a plurality of times or when it is desired to control the droplet shape by different parameters, the droplet application condition optimized for controlling the droplet shape is the droplet application. It is also possible to use the environment such as temperature and humidity at that time, the solvent composition ratio of the applied droplet component, and the like.

The movement is not limited to the stage side, and the head side or both the head and the stage may be moved. Further, FIG. 1 shows an example in which the head is arranged above the substrate, but conversely, the head may be arranged below and ejected from below, or may be arranged laterally and ejected.

Example 1 An electron source substrate having a large number of surface conduction electron-emitting devices was produced using a substrate on which wirings and device electrodes were formed in a matrix.

Below, FIG. 1, FIG. 2, FIG. 4, and FIG.
Description will be made with reference to the drawings.

A glass substrate was used as the insulating substrate 1, which was thoroughly washed with an organic solvent or the like and then dried at 120 ° C. A pair of device electrodes having an electrode width of 500 μm and an electrode gap of 20 μm were formed on the substrate 1 in a matrix of 240 columns, 720 rows, and 172800 sets, and wirings were connected to the electrodes. As this wiring, a matrix wiring as shown in FIG. 5 was adopted. In addition, a droplet shape measuring / correcting element electrode (not shown) was formed in a region outside these image regions.

After cleaning the substrate with an alkaline cleaning solution or the like,
Surface treatment was performed using a silane-based water repellent treatment agent.

Then, the substrate was adsorbed to the stage 8 shown in FIG. 1 to align the pattern.

Further, a solution containing the material for forming the conductive thin film 4 was injected into the ejection head 7 as ink. The solution was an organic palladium-containing solution (palladium-proline complex 0.
15 wt%, isopropyl alcohol 15%, ethylene glycol 2.0%, polyvinyl alcohol 0.05%
Aqueous solution) was used.

Next, the stage 8 is attached to the droplet shape measuring element electrode of the substrate 1 described above, and the stage 8 is scanned at a scanning speed of 20.
While scanning in the + X direction at 0 mm / sec, the position detection mechanism 17 and the inkjet control / driving mechanism 16 simultaneously send ejection signals to the nozzles at the designed ejection timing to eject droplets and deposit them on the substrate. Let In this example, the droplets were applied to one electrode pair four times. In addition, the time interval of the repeated striking at this time was about 7.5 sec.

After that, the observation mechanism 13 and the image processing device 14
By capturing the image of the droplet actually attached, the value obtained by dividing the light intensity at the center of the droplet by the light intensity at the edge is defined as the unevenness ratio from the intensity ratio distribution of the reflected light of the droplet, and Comparison was made with the unevenness rate of the liquid droplets required for forming the conductive thin film. In this embodiment, the end is the midpoint between the center of the droplet and the end of the droplet. The position of the end portion for defining the unevenness ratio is not limited to this, and may be any position between the center portion of the droplet and the end portion of the droplet. In this embodiment, the target unevenness ratio is 1.0 ±
As compared with 0.1, the unevenness rate of the droplets attached on the substrate is 1.2.
It was 5.

As a result of the measurement, it was found that the adhered droplet was more convex in the central portion than the target value.
The scanning speed of the stage 8 is changed from 200 mm / sec to 100 mm in order to form a droplet in which this difference is corrected.
/ Sec, and the time interval of repeated striking is 9.0 sec.
Then, the liquid droplets were applied onto unused liquid crystal shape correction element electrodes (not shown) provided on the same substrate. As a result, the corrected liquid droplet unevenness rate is 1.03, which is the target value 1.
I was able to control it to 0 ± 0.1.

Next, on the basis of the above correction conditions, the droplet 1 is placed at the position on the substrate 1 where the conductive thin film 4 is to be formed.
2 is discharged and adhered, and then heat treatment is performed at 350 ° C. for 30 minutes to obtain 100 Å film thickness of palladium oxide (Pd
O) A conductive thin film 4 made of fine particles was formed.

Further, a voltage is applied between the electrode pair 2 and 3,
The electron-emitting portion 5 was formed by subjecting the conductive thin film 4 to an energization process (energization forming).

In this embodiment, the cross-sectional shape of the adhered droplets before correction was more convex than the target cross-sectional shape. However, if it is concave, the stage feed speed is changed, contrary to the present embodiment. It suffices to raise it so as to shorten the overlapping ejection interval and make a correction so that the droplet becomes more convex.

In this embodiment, the target value of the unevenness rate of the liquid droplets is set to a region considered to be flat, but it can be set to be more concave or more convex if necessary.

In the present embodiment, the modulation of the scanning speed of the stage is used to control the over-printing interval, but in some cases, the coating action may be intentionally stopped or the waiting time may be reduced. It is also possible to modulate the time interval of overstrike.

A display panel was manufactured by combining a face plate, a support frame and the like with the electron source substrate manufactured in this way, and further a drive circuit was connected to manufacture an image forming apparatus.

The electron-emitting device manufactured as described above by the manufacturing method of this embodiment has uniform device characteristics, and a good image forming apparatus can be obtained with good yield.

(Embodiment 2) The basic method is the same as that of Embodiment 1, but in this embodiment, a temperature / humidity control device (not shown) attached outside the device is used as a means for correcting the uneven shape of the droplet. The method of changing the humidity was adopted.

Specifically, since the initial concave-convex ratio of the droplet was 1.23 in this embodiment, the humidity around the substrate was lowered from 40% to 35% by the temperature / humidity control device. By this method, the unevenness ratio of the droplet was set to 1.02, and it was possible to control it within the target value of the unevenness ratio of 1.0 ± 0.1.

In this embodiment, the cross-sectional shape of the adhered droplets before correction was more convex than the target cross-sectional shape. However, if it is concave, the humidity around the substrate is changed in the opposite manner to this embodiment. It is sufficient to raise it to make it more convex.

In this embodiment, the target value of the liquid droplet unevenness ratio is set to a region considered to be flat, but it can be set to be more concave or more convex as required.

According to the method of this embodiment, the first embodiment
Unlike 2 and 2, it is possible to control the concave-convex shape of the droplet even in the case where the droplet is not repeatedly applied to the same place a plurality of times.

Further, when an electron-emitting device and an image forming apparatus were manufactured using these electron source substrates in the same manner as in Example 1, a good image forming apparatus could be obtained with a high yield.

(Embodiment 3) The basic method is the same as that of Embodiment 1, but in this embodiment, a method of changing the solvent ratio in the ink is adopted as a means for correcting the uneven shape of the droplet.

Specifically, since the unevenness rate of the initial droplets was 1.22 in this embodiment, the concentration of the low volatile component, specifically ethylene glycol, in the ink supplied from the head was 1. It was reduced to 5%. According to this method, the target value of the unevenness ratio of 1.0 ± 0.
In this embodiment, the cross-sectional shape of the adhered droplets before correction was more convex than the target cross-sectional shape, but in the case of being concave, contrary to the present embodiment, It suffices to increase the concentration of low volatile components in the ink, such as ethylene glycol, so as to make the correction more convex.

In this embodiment, the target value of the liquid droplet unevenness ratio is set to a region considered to be flat, but it can be set to be more concave or more convex as required.

According to the method of this embodiment, the first embodiment
Unlike 2 and 2, it is possible to control the concave-convex shape of the droplet even in the case where the droplet is not repeatedly applied to the same place a plurality of times.

Further, when an electron-emitting device and an image forming apparatus were manufactured using these electron source substrates in the same manner as in Example 1, a good image forming apparatus could be obtained with good yield.

[0074]

As described above, according to the present invention,
In a method of manufacturing an electron source substrate, which comprises a step of discharging droplets of a metal-containing solution and attaching the droplets to a substrate, the method of manufacturing the electron source substrate includes at least a plurality of discharge nozzles provided in a discharge head. By means of more ejecting means and means for controlling the relative position of the ejecting head and the substrate, at least one of the ejecting head and the substrate is relatively moved, and droplets are adhered onto the substrate from the plurality of ejecting nozzles. And a step of attaching the droplet onto the substrate,
At least a step of detecting a protrusion of a droplet discharged from the discharge nozzle and adhering to the substrate, a step of calculating a deviation amount between the measured protrusion and a target droplet or a protrusion of an electron source, By correcting the calculated shift amount, a conductive thin film having a desired cross-sectional shape can be formed regardless of various disturbance factors. Therefore, in the step of forming an electron-emitting portion by conducting electricity to the conductive film. In addition, it is possible to reduce defective formation of the emission portion, and as a result, it is possible to produce an electron emission source having good electron emission characteristics with a high yield.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an example of a method for manufacturing an electron-emitting device according to the present invention.

FIG. 2 is an explanatory view schematically showing the concept of a method for manufacturing an electron-emitting device according to the present invention.

FIG. 3 is a schematic diagram showing a conventional method for manufacturing an electron-emitting device.

FIG. 4 is a plan view of a surface conduction electron-emitting device manufactured by the manufacturing method of the present invention.

FIG. 5 is an explanatory diagram of a conventional electron-emitting device.

[Explanation of symbols]

1 substrate 2,3 element electrodes 4 Conductive thin film 5 Electron emission part 6 insulating film 7 Discharge head 8 substrate stage 9 discharge nozzles 10 column direction wiring 11 row wiring 12 droplets 13 Droplet observation mechanism 14 Image processing device 15 Control computer 16 Inkjet control / drive mechanism 17 Position detection mechanism

Claims (12)

[Claims] 1. A conductive thin film for communicating between a pair of device electrodes and a plurality of electron-emitting devices having electron-emitting portions on a part of the conductive thin film are arranged on a substrate, and wiring between the electron-emitting devices is provided. And a method for manufacturing an electron source substrate on which a voltage application terminal to the element is formed, wherein the method for manufacturing the electron source substrate is a discharge nozzle in which a droplet of a solution containing at least a metal element is provided in a discharge head. The liquid is ejected from the ejection nozzles provided in the ejection head while relatively moving at least one of the ejection head and the substrate by means of ejecting more liquid and means for controlling the relative position of the ejection head and the substrate. A step of depositing a droplet on the substrate, wherein the step of depositing the droplet on the substrate comprises at least a step of detecting a protrusion of the droplet discharged from the discharge nozzle and deposited on the substrate; Raised Method of manufacturing an electron source, characterized in that it comprises a step of calculating a shift amount between the ridges of the droplets to target, the step of correcting the basis droplet shape deviation amount the calculated. 2. The electron according to claim 1, wherein the step of detecting the protrusion of the droplet is based on an optical image obtained by reflected light or transmitted light when the droplet is irradiated with light. Source manufacturing method. 3. The method of manufacturing an electron source according to claim 1, wherein the step of detecting the protrusion of the droplet is performed by a light intensity ratio signal of the optical image. 4. The electron source according to claim 1, wherein the step of correcting the droplet shape is performed by controlling the temperature or humidity around the substrate when the droplets are applied. Production method. 5. The method of manufacturing an electron source according to claim 1, wherein the step of correcting the droplet shape is performed by optimizing the composition of the solution containing the metal element. 6. The step of depositing the droplet on a substrate comprises:
The method of manufacturing an electron source according to claim 1, wherein the step of correcting the shape of the droplets includes the step of applying the droplets at least once in a plurality of layers so as to overlap each other. The method of manufacturing an electron source according to claim 1, wherein the method is performed by controlling 7. The method of manufacturing an electron source according to claim 1, wherein the ejection head is an inkjet type. 8. A method according to claim 1, wherein a plurality of ejection heads are used.
7. The method for manufacturing an electron source according to 7. 9. The manufacturing method according to claim 1, wherein the ink jet method is a method in which bubbles are formed in the solution by thermal energy and the solution is ejected. 10. The ink jet method is a method of ejecting a solution by mechanical energy.
9. The method for manufacturing an electron source according to item 9. 11. When forming the electron source substrate, column-direction wirings and row-direction wirings are arranged in rows and columns through an insulating layer, and one of the pair of device electrodes is connected to the insulating substrate. The method of manufacturing an electron source according to claim 1, wherein the wiring is in the column direction and the other is connected through an insulating layer to form the wiring in the row direction. 12. An electron-emitting device as an electron source, a voltage applying means to the device, a light-emitting body that emits light by receiving electrons emitted from the device, and a voltage applied to the device based on an external signal. A method for manufacturing an image forming apparatus, comprising: a drive circuit for controlling the electron emission device, wherein the electron-emitting device is provided.
1. A method for manufacturing an image forming apparatus, which is manufactured by the method described in any one of 1.