JPH1069868A - Phosphor light emitting device and method of manufacturing the same - Google Patents

Abstract

(57) [Problem] To provide a phosphor light emitting device that emits light efficiently by including a cathode portion that stably emits thermoelectrons at a low temperature. SOLUTION: By disposing a plurality of fine diamond particles, for example, on the surface of the cathode material which is an electron emission source, it is possible to obtain a cathode which can easily emit thermoelectrons. As a result, a phosphor light emitting device that emits light with high efficiency can be obtained. The average particle size is 0.2 μm
The following step of distributing the fine diamond particles to the surface of the cathode material or to the surface layer is included, so that the diamond that facilitates thermionic emission is arranged with good reproducibility on the surface of the cathode material or to the surface layer in the form of fine particles or aggregates thereof. As a result, a highly efficient phosphor light emitting device can be easily formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phosphor light emitting device for emitting a phosphor by irradiating an electron beam and a method for manufacturing the same, and more particularly, to a cathode having a particulate diamond disposed on a surface or a surface layer as a component. The present invention relates to a phosphor light emitting device and a method for manufacturing the same.

[0002]

2. Description of the Related Art As a typical phosphor light emitting device for emitting a phosphor by irradiation with an electron beam, there is an image display device such as a display. In this technique, an image is displayed by scanning an electron beam emitted from a cathode, which is an electron emission source, and causing a phosphor at an arbitrary position to emit light. In general, examples of the cathode include an electron gun using thermoelectrons emitted from a refractory metal such as tungsten (W), and a cold cathode device that emits electrons from a fine projection structure in a field. In particular, the latter is drawing attention as an electron source for a thin flat display.

As another device for emitting light from a phosphor, there is a lighting device represented by a fluorescent lamp. This discharges a gas filled in a sealed container and causes the phosphor to emit light by the energy of electrons or ultraviolet rays emitted at the time of the gas discharge.

[0004]

A cathode ray tube used in a general image display device emits a phosphor by scanning an electron beam emitted from a single electron gun, so that an appropriate image is obtained. For this purpose, an appropriate distance was required between the electron gun and the phosphor surface. That is, since the depth is required, it is difficult to reduce the thickness of the image display device.
Further, the emission of electrons is due to thermionic emission from the refractory metal.
℃ or more).

Although an image display device in which cold cathode elements are arrayed to form a flat cathode can be made thin, the amount of electron emission obtained largely depends on the shape of the electron emission portion. In order to obtain this, it was necessary to precisely control the structure and shape of the cold cathode portion. That is, it has been difficult to manufacture a stable image display device in terms of, for example, uniformly manufacturing the electron emission portion and maintaining the shape of the electron emission portion.

In view of the prior art from the above viewpoint,
It has been difficult to produce a stable, efficient, and space-saving electron emission source in an image display device that emits phosphor by electron beam irradiation.

[0007] Lighting equipment such as fluorescent lamps emit light from a phosphor by the energy of electrons or ultraviolet rays emitted at the time of gas discharge. In order to increase the luminous efficiency, mercury is contained in a sealed container. Is mixed in. In other words, there is a problem that toxic substances must be used in protecting the global environment.

In order to solve the above-mentioned problems in the prior art, the present invention includes a structure in which a plurality of particles or aggregates of particles are arranged on a surface or a surface layer of a cathode material as an electron emission source. Another object of the present invention is to provide a phosphor light-emitting device such as an image display device or a lighting fixture that can easily and efficiently emit a phosphor, since efficient and stable electron beam emission is possible.

In the method of the present invention, the average particle size is 0.2 μm
By including the following step of arranging particulate diamond on the surface of the cathode material or on the surface layer, a method for producing a phosphor light emitting device having a cathode capable of easily emitting a phosphor as a component is described. The purpose is to provide.

Further, the method of the present invention easily and rationally controls a production process important for producing a high-efficiency phosphor light emitting device in which particulate diamond is arranged on a cathode material, and a surface state control of particulate diamond. The aim is to provide a method.

[0011]

In order to achieve the above object, a phosphor light emitting device according to the present invention comprises at least a sealed container, a phosphor layer disposed inside the container, A phosphor light emitting device comprising a cathode that irradiates the phosphor layer with an electron beam, wherein a plurality of particles, or aggregates of particles are arranged on a surface or a surface layer of a cathode material as an electron emission source. It is characterized by including.

In the present invention, it is preferable that the cathode material as an electron emission source has a linear structure in the above-described device configuration.

In the present invention, it is preferable that the average particle diameter of the particles disposed on the surface or the surface of the cathode material is 0.2 μm or less. More preferably, the average particle size of the particles is 0.05 μm or less.

Further, in the present invention, in the above-mentioned apparatus configuration, it is preferable that the particles or the aggregates of the particles disposed on the surface or the surface layer of the cathode material are made of diamond.

Further, the present invention preferably has a structure in which the carbon atoms on the surface of the cathode material or on the outermost surface of diamond arranged on the surface layer are terminated by bonding with hydrogen atoms. More preferably, the amount of hydrogen bonded to carbon atoms on the outermost surface of diamond is 2 × 10 ¹⁵ atoms / cm ² or more.

In order to achieve the above object, at least a sealed container according to the present invention, a phosphor layer disposed inside the container, and a cathode for irradiating the phosphor layer with an electron beam are provided. The method for manufacturing a phosphor light emitting device is characterized by including a step of distributing particulate diamond having an average particle size of 0.2 μm or less on the surface or the surface layer of the cathode material.

In order to achieve the above object, a method for manufacturing a phosphor light emitting device according to the present invention, wherein the average particle size is 0.2 μm
The method is characterized in that the method includes the following steps of distributing particulate diamond on the surface or surface layer of the cathode material, and growing a diamond layer on the particulate diamond.

Further, the present invention is characterized in that in the above manufacturing method, the method of distributing the particulate diamond on the surface or the surface layer of the cathode material comprises the step of: It is preferably applied to More preferably, the average particle size of the particulate diamond used is 0.05 μm or less.

The present invention also relates to the above method, wherein the method for distributing the particulate diamond on the surface of the cathode material or on the surface layer is as follows. It is preferable to install a material and apply ultrasonic vibration to the solution. More preferably, the average particle size of the particulate diamond used is 0.05 μm or less.

Further, the present invention is characterized in that in the above manufacturing method, the method for distributing the particulate diamond on the surface of the cathode material or on the surface layer is as follows. It is preferable that a material is installed and a voltage is applied between the conductive portion of the cathode material and a container containing the solution, or between the conductive portion of the cathode material and an electrode provided in the solution. More preferably, the average particle diameter of the particulate diamond used is 0.1.
It is not more than 05 μm.

In order to achieve the above object, a method of manufacturing a phosphor light emitting device according to the present invention is characterized in that after disposing particulate diamond on a cathode material, the cathode material is obtained by subjecting a gas containing at least hydrogen to discharge decomposition. And exposing the cathode material to a gas containing at least hydrogen.

According to the structure of the present invention, at least a phosphor light emitting device including a sealed container, a phosphor layer disposed inside the container, and a cathode for irradiating the phosphor layer with an electron beam. In order to include a configuration in which a plurality of particles, or aggregates of particles are arranged on the surface or surface layer of the cathode material that is an electron emission source,
The following effects can be obtained.

FIG. 1 is an example of a sectional view showing a basic structure of a phosphor light emitting device according to the present invention. As shown in FIG. 1, the present phosphor light emitting device includes, as main components, a cathode section 1, a phosphor section 2, a conductive layer 3, and a sealed container 4.
Consists of Here, a plurality of particles or aggregates 5 of the particles are arranged on the surface or the surface layer of the cathode portion 1.

The material of the cathode section 1 used in the present invention,
The shape is the same as that used conventionally,
Although not particularly limited, for example, tungsten (W) or tantalum (Ta) wire (diameter: about several tens of μm)
Alternatively, a W layer patterned on an insulating substrate can be used. In addition, the phosphor part 2, the conductive layer 3, and the sealed container 4 can be exactly the same as those conventionally used.

The cathode section 1 is energized and heated in the same manner as in the prior art, and thermions 6 are emitted by heating. A plurality of particles or aggregates of particles are arranged on the surface of the cathode section 1 or on the surface layer. In the conventional structure that does not have the above, heating at least 700 ° C. or more is required to sufficiently emit the thermoelectrons 6, whereas in the present configuration, the particles or the aggregates 5 of the particles arranged on the cathode material are required. By the action, thermionic electrons 6 are easily emitted, and stabler thermoelectron emission at a lower temperature is possible.

The configuration example of such a phosphor light emitting device is not limited to the configuration shown in FIG. 1; for example, as shown in FIG. A configuration in which a plurality of particles or agglomerates 5 of particles are arranged only in the opposed region) may be used. Further, an extraction electrode 7 for facilitating emission of thermoelectrons 6 from the cathode portion 1
(FIG. 3) between the cathode portion 1 and the phosphor portion 2 or a configuration in which the conductive layer 3 disposed on the inner surface of the sealed container 4 is eliminated and only the extraction electrode 7 is provided (FIG. 4). But it is possible. Further, a configuration in which the extraction electrode 7 is integrated with the cathode section 1 via the insulator layer 8 (FIG. 5) may be employed.

According to the preferred embodiment of the present invention, in which the cathode portion 1 as an electron emission source has a linear structure, a linear electron emission source can be easily obtained. It is most suitable as an electron emission source for flat displays.

In the apparatus of the present invention, the average particle diameter of the particles disposed on the surface or the surface of the cathode material is 0.2 μm or less, and more desirably, the average particle diameter of the particles is 0.05 μm or less. According to the preferred example described above, it is possible to arrange a large number of regions where thermionic emission becomes easy in the cathode section 1. That is, the distribution density of particles or particle aggregates 5 arranged on the surface of the cathode material or on the surface layer can be arranged at a high density of at least 1 × 10 ¹⁰ or more per square centimeter, so that it is easily increased. It becomes possible to obtain thermionic emission.

In a preferred embodiment in which the particles arranged on the surface of the cathode material or on the surface layer or the aggregates of the particles are made of diamond in the device configuration of the present invention, diamond is a wide bandgap semiconductor (5. 5e
V), which has very suitable properties as an electron-emitting material such as high hardness, abrasion resistance, high thermal conductivity, and chemical inertness. It is possible to realize a phosphor light emitting device having the same.

Further, in the apparatus configuration of the present invention, a structure in which carbon atoms on the surface of the cathode material or on the outermost surface of diamond disposed on the surface layer are terminated by bonding with hydrogen atoms, more preferably, on the outermost surface of diamond. According to a preferred example including a structure in which the amount of hydrogen bonded to carbon atoms is 2 × 10 ¹⁵ atoms / cm ² or more, the surface of the hydrogen-terminated diamond is in a negative electron affinity state. This makes it possible to easily emit electrons.

Further, according to the method of the present invention, at least a phosphor light emitting device comprising a sealed container, a phosphor layer disposed inside the container, and a cathode for irradiating the phosphor layer with an electron beam. The method for manufacturing a device, which comprises a step of distributing particulate diamond having an average particle size of 0.2 μm or less on the surface of the cathode material or on the surface layer, so that the following effects can be obtained. it can.

In other words, diamond which facilitates thermionic emission can be arranged in the form of fine particles or agglomerates thereof on the surface of the cathode material or the surface layer with good reproducibility. Can be formed. As a result, an efficient phosphor light emitting device can be easily formed.

Further, the same effect can be obtained by a structure in which a diamond layer is grown using fine diamond particles arranged on the surface of the cathode material or on the surface layer as nuclei. A sufficient effect can be obtained by setting the average particle diameter of the particulate diamond used to 0.2 μm or less as described above, but the smaller the better, the better the average particle diameter is desirably 0.05 μm or less.

In the method of the present invention, the method of distributing the particulate diamond on the surface of the cathode material or the surface layer is such that a solution in which particulate diamond having an average particle size of 0.2 μm or less is dispersed is applied to the cathode material. Or placing the cathode material in a solution in which particulate diamond having an average particle size of 0.2 μm or less is dispersed, and applying ultrasonic vibration to the solution, or a container containing the conductive material of the cathode material and the solution. According to the preferred example of applying a voltage between the electrodes or between the conductive portion of the cathode material and the electrode provided in the solution, the cathode material can be uniformly and arbitrarily applied to a cathode material having an arbitrary shape such as a linear or plate shape. It becomes possible to distribute the particulate diamond with good controllability and reproducibility. In addition, the distribution position of the particulate diamond can be selected.

At this time, the amount of the particulate diamond dispersed in the solution to be used is 0.1 to 1 liter of the solution.
The amount is from 01 g to 100 g, and more preferably from 0.1 g to 20 g per liter of the solution. The specific optimal diamond particle amount depends on the average particle size of the diamond particles used, and is approximately 1 g when the particle size is 0.01 μm and approximately 16 g when the particle size is 0.04 μm.
It is about. In such a solution, about 1 × 10 ¹⁶ to 1 × 10 ²⁰ particulate diamonds are dispersed per liter of the solution, so that a sufficient amount of fine diamond particles can be easily distributed to the cathode material. It is possible. As a dispersion medium for the solution to be used, a solution containing water or alcohol as a main component is mainly used for ease of handling.

In the structure of the cathode portion of the phosphor light emitting device of the present invention, it is very important to control the surface of the arranged particulate diamond. This is because thermionic emission characteristics change depending on the surface state of diamond. The method for optimizing the surface structure of the particulate diamond is not particularly limited, but is a method that can easily control the elements that bond to carbon atoms on the diamond surface. As a specific example, the use of a hydrogen-terminated surface allows diamond to be in a state where thermoelectrons are easily emitted. By arbitrarily controlling such surface state changes,
The configuration and the manufacturing process of the high efficiency phosphor light emitting device can be simplified.

Therefore, according to the method of the present invention, after the particulate diamond is arranged on the cathode material, the cathode material is exposed to a plasma obtained by discharge-decomposing at least a gas containing hydrogen, or Is characterized by having a step of heating in a gas containing at least hydrogen, so that it is possible to selectively bond hydrogen atoms to the outermost carbon atoms of the diamond particles, thereby easily emitting thermoelectrons. It becomes possible to form a region in an easy state.

As described above, by arbitrarily controlling the surface state of diamond disposed on the cathode material, the structure and manufacturing process of the high efficiency phosphor light emitting device can be simplified.

[0039]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described more specifically with reference to examples.

<First Embodiment> First, the results when fine diamond particles are used as the particles arranged in the cathode material will be described.

First, a cathode material is prepared. The material used as the cathode material is not particularly limited,
In this embodiment, a tungsten (W) wire having a diameter of 20 μm is used. Next, the W line was cleaned in a normal washing step, and then penetrated into a solution in which fine diamond particles having an average particle size of 0.02 μm were dispersed, so that the fine diamond particles were applied to the surface thereof. In this embodiment, a solution in which 0.4 g of diamond particles is dispersed in 1 liter of pure water is used. That is, a solution containing approximately 2 × 10 ¹⁷ diamond particles per liter of solution was used. After the application of the diamond particles, the W line was dried by irradiation with an infrared lamp light.

When the surface of the W line obtained by the above method was observed with a scanning electron microscope, it was confirmed that minute diamond particles were scattered and distributed. Its distribution density was about 5 × 10 ¹⁰ pieces / cm ² .

W on which the fine diamond particles are arranged
The wire was placed in a vacuum of 10 ⁻⁷ Torr or less, and heated by energizing the W wire. As a result, it was confirmed that thermoelectrons were emitted in a temperature range of about 300 to 400 ° C. On the other hand, in the case of a conventional W line in which fine diamond particles are not arranged, heating at 700 ° C. or more was required to obtain the same thermoelectron emission. That is, it was confirmed that the W-line cathode on which the fine diamond particles were arranged functions as an efficient thermoelectron emission source.

Then, several tens of W lines on which fine diamond particles are arranged are further stretched on the support member, and the respective W lines are energized and heated (temperature: about 400 ° C.) to obtain thermoelectrons. Irradiation was performed on the R, G, and B corresponding phosphors, and it was confirmed that light emission with sufficient luminance was obtained.

In the present embodiment, when the type of the cathode material is changed to another material, for example, tantalum (Ta), or the shape or size of the cathode material is changed, and the particle size or amount of the diamond particles to be applied is changed. Similar results were obtained when the solution was prepared in a different manner, when an alcohol such as ethanol was used as a solvent, or when the particles were changed to silicon carbide.

Further, the present inventors set up an extraction electrode between the W line on which the fine diamond particles are arranged and the phosphor portion, and apply a voltage to the extraction electrode to thereby generate the orbit of the emitted thermoelectron current. It was also confirmed that it was possible to control

<Second Embodiment> Similar to the first embodiment, a case where fine diamond grains are arranged on a W line having a diameter of 20 μm and a diamond layer is further grown using the diamond grains as nuclei. The results are described.

The cathode material to be used and the method of arranging the fine diamond particles on the W line are the same as those in the first embodiment. In the present embodiment, a W layer is penetrated into a dispersion solution of fine diamond particles to apply fine diamond particles to the surface, and then a diamond layer is formed on the diamond particles distributed on the surface of the W line. The method for synthesizing the diamond layer is not particularly limited, but is often used because the vapor phase synthesis method is easy. The gas phase synthesis method generally uses methane, ethane, ethylene,
It is carried out by using a hydrocarbon gas such as acetylene, an organic compound such as alcohol or acetone, or a carbon source such as carbon monoxide diluted with hydrogen, and decomposing the raw material gas. At that time, oxygen, water or the like can be added to the raw material gas as appropriate. Although there is no particular limitation on the applicable gas phase synthesis method, a diamond layer was formed by a microwave plasma CVD method in this example. The microwave plasma CVD method is a method of forming a diamond by applying a microwave to a source gas to form diamond. As specific conditions, a carbon monoxide gas diluted to about 1 to 10 vol% with hydrogen was used as a source gas. The reaction temperature and pressure are 800-900 ° C and 25-40 Torr, respectively.
It is. A formation time of about 1 to 5 minutes is sufficient.

As a result of forming a CVD diamond layer on the fine diamond particles on the W line by the above method, the surface of the fine diamond particles arranged by coating was coated with a high quality CVD diamond layer. The surface state of the obtained diamond particles was a state terminated by hydrogen.

The W line on which the diamond particles produced by such a procedure are arranged is placed in a vacuum of 10 ⁻⁷ Torr or less, and is heated by energization. As a result, thermoelectrons are emitted in a temperature range of about 300 to 400 ° C. It was confirmed that it was. Further, since the surface of the hydrogen-terminated CVD diamond layer is very stable, the environment (1 × 10 ⁻⁴ Torr) having a relatively low degree of vacuum is relatively low.
(about r), it was confirmed to have stable thermionic emission characteristics. That is, it was confirmed that the W-line cathode on which the fine diamond particles were arranged functions as an efficient thermoelectron emission source.

Then, when this W line was further heated by heating (temperature: about 400 ° C.) and irradiated to the R, G, and B corresponding phosphors, it was confirmed that light emission with sufficient luminance was obtained.

In the present embodiment, when the type of the cathode material is changed to another material, for example, tantalum (Ta), or when the solution is prepared by changing the particle size and amount of the diamond particles to be applied, furthermore, when the solution is prepared. Similar results were obtained when a diamond layer was formed under the forming conditions.

Further, the present inventors set up an extraction electrode between the W line on which the fine diamond particles were arranged and the phosphor portion, and applied a voltage to the extraction electrode to thereby generate a trajectory of the emitted thermoelectron current. It was also confirmed that it was possible to control

<Third Embodiment> Next, a description will be given of a result when ultrasonic vibration is used as a method of arranging fine diamond grains on the W line.

The cathode material and the like used are the same as those in the first embodiment. In the present embodiment, the cleaned W line is placed in a container containing a solution in which fine diamond particles having an average particle size of about 0.02 μm are dispersed,
By applying ultrasonic vibration to the entire container (hereinafter referred to as “ultrasonic vibration processing”), fine diamond particles were distributed on the W line. In this embodiment, a solution in which 0.4 g of diamond particles is dispersed in 1 liter of pure water is used. The power applied during the ultrasonic vibration processing is 100 W
And the processing time is 5 to 15 minutes. The W line subjected to the ultrasonic vibration treatment was washed in pure water, and then dried by blowing with nitrogen gas.

When the surface of the W line subjected to the ultrasonic vibration treatment was observed with a scanning electron microscope, it was found that the fine diamond particles dispersed in the solution were uniformly distributed. The distribution density was about 1 × 10 ¹¹ / cm ² .

The W line on which the diamond particles produced by such a method are arranged is placed in a vacuum of 10 ^-7 Torr or less, and the W line is heated by energization. It was confirmed that thermoelectrons were emitted from the W line on which the diamond particles were arranged. That is,
It was confirmed that the W-line cathode on which the fine diamond particles were arranged functions as an efficient thermoelectron emission source.

Then, the W line was further heated by heating (temperature: about 400 ° C.) and irradiated to the phosphors corresponding to R, G, and B. As a result, it was confirmed that light of sufficient luminance was obtained.

In the present embodiment, the same applies when the type of the cathode material is changed to another material, for example, tantalum (Ta), or when the solution is prepared by changing the particle size or amount of diamond particles to be applied. Was obtained.

Further, the present inventors set up an extraction electrode between the W line on which the fine diamond particles are arranged and the phosphor portion, and apply a voltage to the extraction electrode to make the trajectory of the emitted thermoelectron flow. It was also confirmed that it was possible to control

<Fourth Embodiment> Next, results obtained when the conditions of the ultrasonic vibration processing are changed are described.

The cathode material used, the solution used for the ultrasonic vibration treatment, and the like are the same as those in the third embodiment. In the present embodiment, the ultrasonic vibration processing of the cathode material was performed under the conditions of an applied power of 350 W and a processing time of 30 minutes. When the surface of the W line subjected to the ultrasonic vibration treatment under these conditions was similarly observed with a scanning electron microscope, it was found that in addition to the fine diamond particles distributed on the W line, the surface was distributed in a form partially embedded in the surface layer of the W line. Many small diamond particles were found. This is considered to be due to the fact that the applied power and the processing time under the ultrasonic vibration processing conditions of the present embodiment are larger than those of the third embodiment. W line surface,
And the distribution density of the fine diamond particles embedded and distributed in the surface layer is further increased to ~ 5 × 10 ¹¹ / c
m ² or so.

The W line on which the diamond particles produced by such a method are arranged is placed in a vacuum of 10 ⁻⁷ Torr or less, and the W line is heated by energization. As a result, about 300 mm is obtained similarly to the third embodiment. It was confirmed that thermoelectrons were emitted in the temperature range of ~ 400 ° C. That is, it was confirmed that the W-line cathode on which the fine diamond particles were arranged functions as an efficient thermoelectron emission source.

Then, when this W line was further heated by energizing (temperature: about 400 ° C.) and irradiated to phosphors corresponding to R, G, and B, it was confirmed that light emission with sufficient luminance was obtained.

In the present embodiment, the same applies to the case where the type of the cathode material is changed to another material, for example, tantalum (Ta), or the case where the solution is prepared by changing the particle size or amount of diamond particles to be applied. Was obtained.

<Fifth Embodiment> Next, as a method of arranging the fine diamond particles on the W line, a result of a case where a diamond layer is formed on the fine diamond particles after ultrasonic vibration treatment is described. .

The cathode material used, the method of distributing the fine diamond particles on the W line, and the like are the same as in the fourth embodiment. The method for forming the diamond layer is the same as in the second embodiment.

As a result of forming a diamond layer on the fine diamond particles by the above-described method, the surface of the fine diamond particles arranged by the ultrasonic treatment has a high quality C.
Coated with a VD diamond layer. The surface state of the diamond particles was a state terminated by hydrogen.

The W line on which the diamond particles produced by such a method are arranged is placed in a vacuum of 10 ⁻⁷ Torr or less, and heated by energization. As a result, thermions are emitted in a temperature range of about 300 to 400 ° C. It was confirmed that it was. Further, since the surface of the hydrogen-terminated CVD diamond layer is very stable, the environment (1 × 10 ⁻⁴ Torr) having a relatively low degree of vacuum is relatively low.
(about r), it was confirmed to have stable thermionic emission characteristics. That is, it was confirmed that the W-line cathode on which the fine diamond particles were arranged functions as an efficient thermoelectron emission source.

Then, when this W line was further heated by energizing (temperature: about 400 ° C.) and irradiated to phosphors corresponding to R, G, and B, it was confirmed that light emission with sufficient luminance was obtained.

<Sixth Embodiment> Next, a cathode material is placed in a solution in which fine diamond particles are dispersed, and a voltage is applied between the cathode material and an electrode placed in the solution to apply a voltage to the cathode material. The results obtained by arranging the fine diamond particles in FIG.

The cathode material used is the same as in the above embodiment. Subsequently, the cathode material and a flat plate electrode made of platinum are placed in a container containing a solution in which fine diamond particles having an average particle size of about 0.02 μm are dispersed, and a DC voltage is applied between the W line and the platinum electrode. (Hereinafter referred to as “voltage application processing”), thereby distributing the fine diamond particles to the W line. In this embodiment, a solution in which 0.4 g of fine diamond particles are dispersed in 1 liter of pure water is used. The conditions of the voltage application process were as follows: the platinum electrode side was the negative electrode,
A voltage of 50 V was applied for 15 minutes using the W line side as a positive electrode. After the voltage applied W line is washed with pure water,
Dried by blowing with nitrogen gas.

When the surface of the W line subjected to the voltage application treatment was observed with a scanning electron microscope, it was found that W
It was found that the fine diamond particles were uniformly distributed on the wire surface. The distribution density is up to 3 × 10 ¹⁰ pieces / cm ²
It was about. This is probably because the colloidal fine diamond particles in the solution had a negative charge and were attracted to the W line by the voltage application process.

The W line on which the fine diamond particles produced by such a method are arranged is placed in a vacuum of 10 ⁻⁷ Torr or less and heated by energization. As a result, about 300 to 400 as in the third embodiment. It was confirmed that thermoelectrons were emitted in the temperature range of ° C. That is, it was confirmed that the W-line cathode on which the fine diamond particles were arranged functions as an efficient thermoelectron emission source.

Then, the W line is further heated by energization (temperature:
(About 400 ° C.) and irradiating the phosphor corresponding to R, G, B, it was confirmed that light emission with sufficient luminance was obtained.

In the present embodiment, when the type of the cathode material is changed to another material, for example, tantalum (Ta), or when the solution is prepared by changing the diameter and amount of diamond particles to be applied, a platinum electrode is used. Similar results were obtained when a conductive container was used as the negative electrode.

<Seventh Embodiment> Next, as a method of distributing fine diamond particles on the W line, a result in the case where a diamond layer is formed on fine diamond particles after applying a voltage application process will be described.

The cathode material used, the amount of fine diamond particles dispersed in the solution used for the voltage application process, and the like are the same as in the sixth embodiment. Also, the method of forming the diamond layer is the same as in the third embodiment.

As a result of forming the diamond layer on the fine diamond particles by the above-described method, the surface of the diamond particles arranged by the voltage application treatment has a good quality.
Coated with a diamond layer. The surface state of the diamond particles was a state terminated by hydrogen.

The W line on which the diamond particles produced by such a method are arranged is placed in a vacuum of 1 × 10 ⁻⁷ Torr or less and heated by electric current. Was confirmed to have been released. Also, since the surface of the hydrogen-terminated CVD diamond layer is very stable, the environment (1 × 10 ⁻⁴ T
(about orr), it was confirmed that the composition had stable thermionic emission characteristics. That is, it was confirmed that the W-line cathode on which the diamond particles were arranged functions as an efficient thermoelectron emission source.

Then, this W line is further heated by heating (temperature:
(About 400 ° C.) and irradiating the phosphor corresponding to R, G, B, it was confirmed that light emission with sufficient luminance was obtained.

<Eighth Embodiment> In the present embodiment,
A case in which the process is performed on a W layer pattern patterned on an insulating substrate will be described.

First, the glass as the base material was cleaned in a usual washing step, and then a W layer serving as a cathode portion was formed linearly.

Subsequently, after a silicon dioxide layer to be an insulator layer was formed on the entire surface of the glass substrate by a method such as sputtering or CVD, the photoresist material was patterned. The shape of the patterning is not particularly limited, but in this example, a 20 μm-diameter linear window was formed in the photoresist material on the W layer.

Next, this base material and a flat plate electrode made of platinum were placed in parallel in a container containing a solution in which fine diamond particles having an average particle size of about 0.02 μm were dispersed.
A voltage application process of applying a DC voltage between the layer and the platinum electrode was performed. The conditions of the voltage application processing used in the present embodiment are as follows:
The conditions are the same as in the sixth embodiment. The substrate subjected to the voltage application treatment was washed with pure water, and then dried by blowing with nitrogen gas.

The surface of the substrate subjected to the voltage application was observed with a scanning electron microscope.
It was found that the fine diamond particles dispersed in the solution were uniformly distributed only in the linear portions of the layer. Further, the distribution density was about 3 × 10 ¹⁰ / cm ² .

The substrate having the W layer on which the fine diamond particles produced by the above method are arranged is 1 × 10 ⁻⁷ Torr.
r in a vacuum below, heating the W layer by energizing,
It was confirmed that thermoelectrons were emitted in a temperature range of about 300 to 400 ° C. as in the third embodiment. That is, it was confirmed that the W layer wire cathode on which the fine diamond particles were arranged functions as an efficient thermoelectron emission source.

Then, the W layer is further heated by current (temperature:
(About 400 ° C.) and irradiating the phosphor corresponding to R, G, B, it was confirmed that light emission with sufficient luminance was obtained.

In the present embodiment, when the kind of the cathode material is changed to another material, for example, tantalum (Ta), or when the solution is prepared by changing the diameter and amount of diamond particles to be applied, a platinum electrode is used. Similar results were obtained when a conductive container was used as the negative electrode.

Similar results were obtained when minute diamond grains were arranged on the surface of the cathode material by another method, for example, a method such as ultrasonic vibration treatment.

<Ninth Embodiment> The result of applying the W line on which the fine diamond particles prepared in the first embodiment are arranged to a filament portion used in lighting equipment such as a fluorescent lamp will be described.

The cathode material to be used and the method of arranging the fine diamond grains on the W line are the same as those in the first embodiment.

The W in which the fine diamond particles are arranged
As a result of examining the discharge efficiency of the filling gas in the sealed container due to thermionic electrons emitted from the wire, it was confirmed that gas discharge was performed with higher efficiency than before. As a result, it was confirmed that the phosphor can emit light with the same luminance even when the amount of mercury contained in the sealed container is reduced as compared with the related art.

Tenth Embodiment As a method for controlling the surface structure of diamond particles disposed on the surface of a cathode material, which is a thermionic emission source, the cathode material was exposed to plasma obtained by discharge-decomposing hydrogen gas. The results are described.

First, a W line having fine diamond particles disposed on its surface was prepared by the method described above. Examination of the surface state of the arranged diamond particles revealed that the diamond particles had a surface partially terminated with oxygen. Then, this W line was exposed to ECR discharge plasma of hydrogen gas. The hydrogen plasma irradiation time at that time is 20 seconds. As a result, it was confirmed that the outermost surface carbon in the region exposed to the hydrogen plasma was changed into a bond with hydrogen, and it was found that thermionic emission characteristics were improved. That is, it was confirmed that the surface state of the diamond particles could be controlled by using this process.

When the time of exposing the hydrogen gas to the ECR discharge plasma is changed, or when the hydrogen gas is
Similar results were obtained when diluted to such an extent and when exposed to hydrogen plasma formed by another method.

<Eleventh Embodiment> As a method of controlling the surface structure of diamond particles arranged on the surface of a cathode material, which is a thermionic electron emission source, a result of heating the cathode material in hydrogen gas will be described.

First, a W line having fine diamond particles disposed on its surface was prepared by the method described above. Examination of the surface state of the arranged diamond particles revealed that the diamond particles had a surface partially terminated with oxygen. Therefore, a W line on which fine diamond particles were arranged was set in a cylindrical container in which hydrogen gas was flown, and heated to 600 ° C. The processing time at that time is 10 minutes. As a result, it was confirmed that the outermost surface carbon of the diamond particles heated in the hydrogen atmosphere was changed into a bond with hydrogen, and it was found that the thermoelectron emission characteristic of the W-line cathode was improved. That is, it was confirmed that the surface state of the diamond particles could be controlled by using this process.

When the hydrogen gas flowing into the container is diluted to about 10% with argon or nitrogen, or when the heating temperature is 400 to 90
Similar results were obtained when the temperature was changed in the range of 0 ° C.

[0100]

As described above, according to the phosphor light-emitting device of the present invention, at least the sealed container, the phosphor layer disposed inside the container, and the phosphor layer What is claimed is: 1. A phosphor light-emitting device comprising a cathode for irradiating a line, comprising a structure in which a plurality of particles or aggregates of particles are arranged on a surface or a surface layer of a cathode material as an electron emission source. Therefore, a phosphor light emitting device having a cathode portion having higher efficiency and stable electron emission characteristics can be obtained. Further, in the present invention, by making the shape of the cathode portion, which is an electron emission source, a linear structure,
It is also suitable as an electron emission source for flat displays.

Further, according to the method of the present invention, at least a phosphor luminous device comprising a sealed container, a phosphor layer disposed inside the container, and a cathode for irradiating the phosphor layer with an electron beam. A method of manufacturing a device, comprising a step of distributing particulate diamond having an average particle size of 0.2 μm or less on the surface of a cathode material or a surface layer. In the form of fine particles or their aggregates, it is possible to arrange them with good reproducibility on the cathode surface or surface layer,
As a result, an efficient phosphor light emitting device can be easily formed.

According to the structure of the method of the present invention, after the particulate diamond is arranged on the cathode material, the cathode material is exposed to a plasma obtained by discharge decomposition of a gas containing at least hydrogen. Is characterized by having a step of heating in a gas containing at least hydrogen, so that hydrogen atoms can be selectively bonded to the outermost carbon atoms of diamond, and as a result, thermoelectrons are easily emitted It becomes possible to form a phosphor light emitting device having a cathode portion.

As described above, by arbitrarily controlling the surface state of the diamond disposed on the cathode portion, the configuration and manufacturing process of the high-efficiency phosphor light emitting device can be simplified.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a basic structure of a phosphor light emitting device according to the present invention.

FIG. 2 is a sectional view showing a basic structure of another phosphor light emitting device according to the present invention.

FIG. 3 is a sectional view showing a basic structure of another phosphor light emitting device according to the present invention.

FIG. 4 is a sectional view showing a basic structure of another phosphor light emitting device according to the present invention.

FIG. 5 is a sectional view showing a basic structure of another phosphor light emitting device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cathode part 2 Phosphor part 3 Conductive layer 4 Sealed container 5 Particle or aggregate of particles 6 Thermoelectrons 7 Extraction electrode 8 Insulator layer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsuya Shiratori 1006 Kazuma Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (11)

[Claims] 1. A phosphor light emitting device comprising at least a sealed container, a phosphor layer disposed inside the container, and a cathode for irradiating the phosphor layer with an electron beam, the device comprising: A phosphor light emitting device comprising a structure in which a plurality of particles or aggregates of particles are arranged on a surface or a surface layer of the cathode material as a source. 2. The shape of a cathode material as an electron emission source is as follows:
The phosphor light emitting device according to claim 1, wherein the phosphor light emitting device has a linear structure. 3. The phosphor light emitting device according to claim 1, wherein the average particle diameter of the particles disposed on the surface of the cathode material or on the surface layer is 0.2 μm or less. 4. The phosphor light emitting device according to claim 1, wherein the particles or the aggregates of the particles disposed on the surface or the surface layer of the cathode material are made of diamond. 5. The phosphor emission according to claim 4, wherein carbon atoms on the surface of the cathode material or on the outermost surface of the diamond arranged on the surface layer have a structure terminated by bonding to hydrogen atoms. apparatus. 6. A method for manufacturing a phosphor light-emitting device comprising at least a sealed container, a phosphor layer disposed inside the container, and a cathode for irradiating the phosphor layer with an electron beam. And distributing particulate diamond having an average particle size of 0.2 μm or less on the surface or surface layer of the cathode material. 7. A method for manufacturing a phosphor light-emitting device comprising at least a sealed container, a phosphor layer disposed inside the container, and a cathode for irradiating the phosphor layer with an electron beam. A phosphor light-emitting device, comprising: distributing particulate diamond having an average particle size of 0.2 μm or less on the surface or surface layer of the cathode material; and growing a diamond layer on the particulate diamond. Manufacturing method. 8. The method for distributing particulate diamond on the surface or the surface layer of the cathode material is as follows.
8. The method according to claim 6, wherein a solution in which the following particulate diamond is dispersed is applied to the cathode material.
A method for manufacturing the phosphor light emitting device according to any one of the above. 9. The method for distributing particulate diamond on the surface or the surface layer of the cathode material is as follows:
8. The phosphor light emitting device according to claim 6, wherein a cathode material is provided in a solution in which the following particulate diamond is dispersed, and ultrasonic vibration is applied to the solution. Production method. 10. The method for distributing particulate diamond on the surface or the surface layer of the cathode material is as follows.
The cathode material is placed in a solution in which particulate diamond of m or less is dispersed, and the electrode is placed between the conductive part of the cathode material and the container containing the solution, or the conductive part of the cathode material and the solution. 8. A method for manufacturing a phosphor light emitting device according to claim 6, wherein a voltage is applied between the phosphor light emitting device and the light emitting device. 11. A method of manufacturing a phosphor light emitting device comprising at least a sealed container, a phosphor layer disposed inside the container, and a cathode for irradiating the phosphor layer with an electron beam. After arranging the particulate diamond on the cathode material, exposing the cathode material to a plasma obtained by discharge decomposition of at least a gas containing hydrogen, or heating the cathode material in a gas containing at least hydrogen. A method for producing a phosphor light emitting device.