JP2007317389A - Ink for field electron emission element and method of manufacturing field electron emission element using it - Google Patents

Ink for field electron emission element and method of manufacturing field electron emission element using it Download PDF

Info

Publication number
JP2007317389A
JP2007317389A JP2006142847A JP2006142847A JP2007317389A JP 2007317389 A JP2007317389 A JP 2007317389A JP 2006142847 A JP2006142847 A JP 2006142847A JP 2006142847 A JP2006142847 A JP 2006142847A JP 2007317389 A JP2007317389 A JP 2007317389A
Authority
JP
Japan
Prior art keywords
electron emission
field electron
ink
mayenite type
emission element
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
JP2006142847A
Other languages
Japanese (ja)
Inventor
Setsuo Ito
Madoka Kuwahara
節郎 伊藤
円佳 桑原
Original Assignee
Asahi Glass Co Ltd
旭硝子株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Asahi Glass Co Ltd, 旭硝子株式会社 filed Critical Asahi Glass Co Ltd
Priority to JP2006142847A priority Critical patent/JP2007317389A/en
Publication of JP2007317389A publication Critical patent/JP2007317389A/en
Withdrawn legal-status Critical Current

Links

Images

Abstract

A field electron emission device in which a conductive mayenite compound powder is formed on a bulk conductive mayenite compound and a field electron emission device using the same already existed, but a field electron emission device with higher density energy efficiency. And equipment was sought.
One or more of the mayenite type compounds represented by the chemical formula of 12CaO · 7Al 2 O 3 or 12SrO · 7Al 2 O 3 is contained in an amount of 50 mol% or more, and a part of the constituent oxygen of the mayenite type compound is an electron. The conductive mayenite type compound particles which are substituted and have an electron density of 1 × 10 18 cm −3 or more are contained in an amount of 0.01 to 50% by mass, and the solvent is contained in an amount of 50 to 99.99% by mass. An ink for a field electron emission device is provided.
[Selection figure] None

Description

  The present invention relates to a field electron emission element ink containing a conductive mayenite type compound, a method for producing a field electron emission element using the same, and a field electron emission apparatus using the same.

It is known that a mayenite type compound represented by a chemical formula of 12CaO · 7Al 2 O 3 or 12SrO · 7Al 2 O 3 becomes an ionic crystal in which an electron acts as an anion, that is, an electride by performing a reduction (non-existing) Patent Document 1). Reduced 12CaO.7Al 2 O 3 or 12SrO.7Al 2 O 3 is represented by [Ca 24 Al 28 O 64 ] 4+ (4e ) or [Sr 24 Al 28 O 64 ] 4+ (4e ), and is conductive. It is called a sex mayenite type compound.

  Since the conductive mayenite type compound is inexpensive, it can be applied to electronic materials and nanotechnology in various fields by utilizing its physicochemical characteristics. Among them, the conductive mayenite type compound has attracted attention as a cold electron emission material because its work function, which is one of the indicators of the ease of electron emission, is as extremely small as 0.6 eV. Examples of applications of cold electron emission materials include field emission displays, scanning tunneling microscopes, or field emission microscopes, and research is being conducted for the purpose of application to these applications.

  For example, metals and carbon such as molybdenum (Mo), which are being studied as cold electron emission materials, have a work function of about 4 eV, which is one of the indicators of the ease of electron emission. In order to emit electrons at a low voltage, efforts have been made to increase the electric field concentration coefficient by forming a fine structure. In the case of molybdenum, a field electron-emitting device is known in which a number of emission source chips called a Spindt type having a small triangular pyramid height of about 1 μm are arranged (US Pat. No. 3,665,241). reference). However, it is difficult to manufacture a large number of Spindt-type emission source chips with high accuracy, and it is difficult to increase the area when applied to a surface light emitting device or an image display device.

  In addition, since the electric field concentrates on the tip of the chip and the electric field strength becomes very strong, ions generated by electron emission collide with the tip of the chip with a large momentum and cause damage. As a result, there are problems that electron emission becomes unstable and the lifetime of the emission source is short. In the case of carbon, it is synthesized and used as a carbon nanotube having a linear structure with a diameter of several nanometers to several tens of nanometers and a length of several micrometers, but there is a problem that it is difficult to control the number density of the carbon nanotubes. . As described above, it has been difficult to manufacture electron emission sources composed of Spindt-type molybdenum and carbon nanotubes, FEDs using them, and cold cathode fluorescent tubes.

  On the other hand, since the conductive mayenite type compound has a very small work function of 0.6 eV, the carbon nanotube or spint type electron emission source does not increase the tip end aspect ratio and increase the electric field strength. Electron emission can occur. Chips with a small aspect ratio have stronger mechanical strength at the tip than those with sharp structures. In addition, when a chip having a small aspect ratio is used, since the electric field strength at the tip of the chip is small, the impact generated when the ions generated by electron emission collide with the tip of the chip is weak and is not easily damaged. Furthermore, if the chip has a small aspect ratio, the number of processing processes in vacuum is small, and there is a possibility that a field electron emission device can be easily manufactured. However, until now, a mirror surface obtained by polishing a lump of conductive mayenite type compound has been used as an electron emission source. With this manufacturing method, a very large voltage of 1.5 kV or higher is applied at room temperature. Otherwise, only field electron emission devices in which no electron emission was observed could be manufactured (Non-Patent Document 1).

Adv. Mater. vol. 16, p. 685-689, (2004)

  The present invention has been made in view of the above circumstances, and can easily produce a field electron emission device having high electron emission efficiency, and can achieve a thinner and higher-definition display with good dispersibility. An object of the present invention is to provide an ink for a field electron emission device.

The present invention contains at least 50 mol% of a mayenite type compound represented by the chemical formula of 12CaO.7Al 2 O 3 or 12SrO.7Al 2 O 3 , and a part of the constituent oxygen of the mayenite type compound is substituted with electrons. An electric field comprising 0.01 to 50% by mass of the conductive mayenite type compound particles exhibiting an electron density of 1 × 10 18 cm −3 or more and 50 to 99.99% by mass of the solvent. An ink for an electron-emitting device is provided.

  The ink for a field electron emission device according to claim 1, wherein the solvent for the field electron emission device ink contains a compound having a hydroxyl group having 3 or more carbon atoms, an amide compound, or a sulfur compound.

  Further, the solvent of the field electron emission element ink is 1-propanol, 2-propanol, 1-butanol, or 2-butanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol isopropyl. The above-mentioned ink for field electron emission device comprising ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol isopropyl ether, 1-hexanol, 1-octanol, 1-pentanol, and tert-pentyl alcohol. I will provide a.

Further, the present invention provides an ink for a field electron emission device, wherein the solvent of the ink for a field electron emission device contains N-methylformamide, N-methylpyrrolidone, and dimethyl sulfoxide.
The present invention also provides a method for manufacturing a field electron emission device formed by applying the field electron emission device ink.

  The present invention also provides a field electron emission device having the field electron emission device and an anode electrode used opposite to the electron emission device.

  In the present invention, a flat and thin coating film can be formed by adding the above-mentioned conductive particles to a solvent having a low viscosity when preparing the ink. For this reason, the thickness of the field electron-emitting device portion can be made thinner, which can contribute to higher definition of the display.

  In addition, in the present invention, when the ink is produced, by controlling the above conductive particles to 0.01 to 50% by weight of the solvent, a film in which the field electron emission material is sufficiently dispersed in the thin film is formed. It is possible to adjust the particle density of the emission source. Therefore, by controlling the particle density to an optimum value, a field electron emission device having a large emission current value with a small applied voltage can be realized.

  By using the field electron emission element ink of the present invention, a field electron emission element having a thin film and excellent smoothness and high electron emission ability can be formed. Furthermore, it is possible to provide a field electron emission device having a stable current-voltage characteristic and a large emission current value with a small applied voltage by selecting an appropriate solvent addition amount and a powder concentration of a conductive mayenite type compound. it can. If this field electron emission device is used, a field electron emission device having a high-definition pixel can be provided.

Hereinafter, embodiments of the present invention will be described in detail. In the present invention, the conductive mayenite type compound means that a part of the constituent oxygen of the mayenite type compound represented by the chemical formula of 12CaO · 7Al 2 O 3 or 12SrO · 7Al 2 O 3 is substituted with electrons, and 1 × 10 18. It is a substance that exhibits an electron density of cm −3 or higher. This electroconductive mayenite type compound consists of [Ca 24 Al 28 O 66 ] and a reduced part thereof, [Ca 24 Al 28 O 64 ] 4+ (4e ) or [Sr 24 Al 28 O 64 ] 4+. It has conductivity by containing (4e ) or the like. The ink of the present invention contains the conductive mayenite type compound, and may further contain a compound made of an organic substance such as terpineol or ethyl cellulose as a thickener.

  In the ink of the present invention, the particles of the conductive mayenite type compound serving as the electron emission source are preferably as the circular equivalent diameter R of the cross section of the particles is smaller, but the powder whose circular equivalent diameter of the powder cross section is less than 0.002 μm. Is preferably about 0.002 μm or more because it may be about the same as the unit cell size of the mayenite type compound and may not retain conductivity. On the other hand, when the diameter of the powder in terms of a circle exceeds 5 μm, it is difficult to obtain a sufficient effect as an electron emitter. When used in a cold cathode fluorescent tube and a flat illumination device, the maximum circle-converted diameter of the conductive mayenite type compound powder is preferably 5 μm or less in consideration of the reduction of the element.

  The circle-converted diameter refers to the cross-sectional area (area of the cut surface when the powder is cut on a plane parallel to the substrate) measured by a conventionally known method using image analysis, for example, with a circumference ratio π. It is defined as a value obtained by doubling the square root of the measured value, but it is also possible to obtain an average particle diameter using a particle size distribution measuring apparatus using a dynamic light scattering method and to use this as a circle-converted diameter R. .

  The particles responsible for electron emission contained in the field electron emission element ink of the present invention are conductive mayenite type compounds, and a compound composed of an organic substance can be added as required. Unless the powder contains 50 mol% or more of the conductive mayenite type compound, the desired current may not be obtained due to the small number of carriers included in the crystal. In order to allow a sufficient amount of the conductive mayenite type compound to be present on the exposed powder surface so that sufficient electron emission and conduction with the negative electrode are performed, the conductive mayenite type compound is preferably 70 mol% or more. In order to obtain a sufficiently large current by electron emission, 90 mol% or more is preferable.

  Moreover, it is preferable that the particle | grains containing this electroconductive mayenite type compound are 0.1 S / cm or more in electrical conductivity. If the conductivity is low, excessive Joule heat is generated when electrons are emitted, which may cause emission of adsorbed gas and deterioration of the emitter.

  The conductive mayenite type compound contained in the field electron emission ink of the present invention can be produced, for example, as follows, but other production methods can be used or production conditions can be changed. is there.

A raw material prepared by mixing and mixing CaO or SrO and Al 2 O 3 in a molar ratio of 11.8: 7.2 to 12.2: 6.8 is heated to 1550 to 1650 ° C. in an alumina crucible. Then, after pulverizing, the pulverized powder is pressed into a pellet, heated again to 1550 to 1650 ° C., held and baked. This pellet is put together with one or more powders or fragments of carbon, metal titanium, metal calcium, or metal aluminum into a covered container, heat-treated at a high temperature of 1500 ° C. or higher with the inside of the container kept at a low oxygen partial pressure, and cooled. To do.

  The obtained conductive mayenite type compound is pulverized by mechanically applying compression, shearing and frictional force to the material using a hammer such as metal or ceramics, a roller or a ball. At this time, if a planetary mill using tungsten carbide balls is used, foreign particles are not mixed into the coarse particles of the conductive mayenite type compound, and the coarse particles having a particle size of 50 μm or less can be obtained.

  The obtained conductive mayenite type compound can be pulverized into finer particles having a circle-equivalent diameter of 20 μm or less using a ball mill or a jet mill. It is possible to mix these particles of 20 μm or less with an organic solvent to produce an ink. However, if the conductive mayenite type compound coarsely pulverized to 50 μm or less is mixed with an organic solvent and the beads are pulverized, the ink is finer. Since a dispersion solution in which the conductive mayenite type compound powder having a circle-equivalent diameter of 5 μm or less can be produced, it has a favorable effect on improving the characteristics of the field electron emission device. For example, zirconium oxide beads can be used for bead grinding.

  At the time of the pulverization, for example, when an alcohol or ether is used as the compound having a hydroxyl group having 1 or 2 carbon atoms, the conductive mayenite type compound may react with these and decompose. For this reason, the alcohol-based or ether-based solvent is preferably one having 3 or more carbon atoms. As an organic solvent containing a hydroxyl group having 3 or more carbon atoms, an amide compound, or a sulfur compound, 1-propanol, 2-propanol, 1-butanol, 2-butanol, ethylene glycol monomethyl ether , Ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol isopropyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol isopropyl ether, pentyl alcohol, 1-hexanol, 1-octanol, 1-pentanol, tert -Pentyl alcohol, N-methylformamide, N-methylpyrrolidone, dimethyl sulfoxide and the like are used. Since these can be easily pulverized, these solvents can be used alone or in combination.

  In the field electron emission device according to the present invention, the ink for the field electron emission device is applied on the conductive thin film surface on the substrate with the conductive thin film or on the conductive substrate, and the temperature is from 200 ° C. to 600 ° C. for about 10 minutes. It is obtained by firing. Among these solvents, if the solvent has a boiling point of 120 ° C. or lower as the solvent for the field electron emission element ink, it is easily decomposed by firing. Therefore, 1-propanol, 2-propanol, 1-butanol, 2-butanol, tert-pentyl alcohol, and propylene glycol monomethyl ether are more preferable.

  When a solvent having no hydroxyl group such as acetone, benzene, toluene, xylene, hexane or the like is used as the solvent, the stability is low and the solvent and the conductive mayenite type compound cannot be separated and pulverized in a short time. Thus, when the dispersion stability of the ink is low, the dispersibility is lowered during large-area coating or the like, which causes uneven coating. Although it is possible to produce an ink using a solvent having poor dispersibility and to form a thin film by using a specific coating method, there is a problem in that it is subject to restrictions such as an object to be coated and size.

  Furthermore, the solvent used in the field electron emission ink according to the present invention is preferably one having a low water content. This is because the conductive mayenite type compound may be decomposed by moisture in the solvent, or electrons in the compound may be replaced with hydroxyl groups, resulting in loss of conductivity. For this reason, it is preferable to use after dehydrating the solvent used for a dispersion liquid. Although the method of dehydration is not particularly limited, it can be dehydrated using molecular sieve, anhydrous sodium sulfate, calcium hydroxide or the like. By dehydration, the water content of the solvent is preferably 0.1% by mass or less.

  The field electron emission ink according to the present invention may contain 10% by mass or less of a dispersant and a surfactant in addition to the above components. Further, from the viewpoint of increasing the thickness of the field electron emission ink coating film, an additive such as carbon black may be added to the conductive mayenite type compound dispersion.

  As an example of a method for producing an ink for forming a field electron emission device according to the present invention, after dehydrating the solvent having a low water content, a coarse conductive mayenite type compound of 0.01 to 50 μm or less is used. 50% by mass and the solvent are mixed in the range of 50 to 99.99% by mass, and zirconia beads having a weight 2 to 5 times the solvent are mixed as a pulverizing mill, and the beads are pulverized. For example, a method of dispersing the crystalline mayenite type compound is used. At this time, it is preferable to use a zirconia oxide bead having a size of 0.01 to 0.5 mmΦ because an ink for a field electron emission device containing a conductive mayenite type compound powder having an average particle size of 5 μm or less can be obtained.

  The field electron emission device according to the present invention can be obtained by applying the above-described field electron emission device ink on a substrate with a conductive thin film or a conductive substrate and baking it. Examples of the coating method include spray coating, die coating, roll coating, dip coating, curtain coating, spin coating, and gravure coating, but spin coating and spray coating are particularly easy because the powder density can be manipulated more easily and accurately. preferable. The preferred firing conditions for the ink coating are that the organic molecules of the solvent that is a component of the ink are decomposed, the conductive mayenite type compound is sufficiently fixed to the conductive substrate, and the oxidizing action of the conductive mayenite type compound is not promoted. Such a temperature is preferred. Generally, the range of 200 ° C to 600 ° C is preferable. The firing time is preferably about 10 minutes.

  A field electron emission device can be produced by arranging the field electron emission device produced as described above and the anode electrode so as to face each other in parallel. In order to facilitate the driving of the field electron emission device, it is required that electrons from the field electron emission element can be emitted at a low voltage. In particular, in applications where the emission of electrons is controlled by turning on / off the drive voltage, such as an FED, it is necessary to lower the drive voltage.

In particular, an electron-emitting device having a driving voltage of about 500 V or less is preferable because of low power consumption. In the present invention, a field emission device which is a cathode electrode is grounded with respect to a bipolar field electron emission device, a positive voltage V is applied to the anode electrode using an external power source, and a current flowing between both electrodes is measured. . The measured current value is divided by the area of the anode electrode to determine the V dependence of the current density i [μA / cm 2 ], and the application when the emission current density i becomes 0.1 μA / cm 2 or more. The value of the voltage V was set as the threshold voltage.

  The configuration of a field emission device for measuring threshold voltage characteristics is shown in FIG. A cylindrical copper rod whose bottom surface is polished flat is used as an anode electrode, and the field electron-emitting device and the anode electrode are arranged to face each other in parallel. 2 is an anode electrode, and 4 is a cathode electrode. At this time, the distance between the conductive thin film 3a formed on the base 3 of the field electron emission device and the bottom surface of the anode electrode 2 needs to be adjusted using a glass spacer. In order to increase the electric field intensity on the field electron emission source, the distance is preferably as small as possible, and is preferably 0.1 mm or less. In addition, a silicon wafer, a glass plate, or the like is preferable as the substrate used at that time. Further, it is preferable to use platinum or aluminum as the conductive thin film.

  The present invention will be described more specifically with reference to examples. However, the description is not intended to limit the present invention. Examples 1 to 10 are examples, and examples 11 to 17 are comparative examples, each relating to an ink for a field electron emission device. Example 18 is an example and relates to a field electron emission device and a field electron emission device.

(Example 1)
Calcium carbonate and aluminum oxide were prepared so that the molar ratio of CaO to Al 2 O 3 in terms of oxide was 12: 7, held at 1300 ° C. for 6 hours in an air atmosphere, and then cooled to room temperature. The obtained sintered product was pulverized to obtain a powder having a particle size of 50 μm. The obtained powder (hereinafter referred to as powder A) was a white insulator and was a 12CaO · 7Al 2 O 3 compound having a mayenite structure according to X-ray diffraction.

Powder A is press-molded to form a molded body having a length × width × height of about 2 × 2 × 1 cm, placed in an alumina container with a lid together with 3 g of metal aluminum powder, and heated to 1300 ° C. in a vacuum furnace for 10 hours. Reducing heat treatment was performed. The obtained heat-treated product had a blackish brown color and was identified as a mayenite type compound by X-ray diffraction measurement (Sample B). From the light absorption spectrum obtained by measuring the light diffuse reflection spectrum and converting it by the Kubelka-Munk method, it was confirmed that a strong light absorption band centered at 2.8 eV, which is characteristic of the conductive mayenite type compound, was induced. It was. Further, from the peak intensity of this light absorption band, it was found that the electron density of sample B was 1.4 × 10 21 / cm 3 and had an electric conductivity of 120 S / cm by the van der Pauw method. Further, it was found that the ESR signal of the obtained heat-treated product was an asymmetric type having a g value of 1.994, which is characteristic of a conductive mayenite type compound having a high electron concentration exceeding 10 21 / cm 3 . From the above, it was confirmed that a conductive mayenite type compound was obtained.

  Sample B was manually pulverized with an alumina pestle and mortar, and the resulting pulverized product was pulverized using a planetary mill made of tungsten carbide (Sample C).

  As a solvent, molecular sieve (particle size: 0.3 nm, manufactured by MERCK) was added at a ratio of 100 g to 1 liter of 1-propanol, and after stirring several times, the mixture was allowed to stand for 24 hours. The water content of 1-propanol after dehydration was 0.01 wt%. To 19 g of this dehydrated 1-propanol, 1 g of sample C was mixed with 60 g of 0.1 mmφ zirconia bead oxide as a grinding mill, and these were put in a polyethylene container and rotated and ground for 24 hours (bead grinding). The rotation speed was 400 rpm. In this way, an ink D for field electron emission elements was produced. Ink D contained 5% by mass of a conductive mayenite type compound and 95% by mass of 1-propanol.

  (Example 2) to (Example 17) are each 2-propanol, 1-butanol, 2-butanol, 1-hexanol, 1-pentanol, ethylene glycol isopropyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether as a solvent. Ink was prepared in the same manner as in Example 1 except that N-methylformamide, methanol, ethanol, acetone, benzene, toluene, xylene, and hexane were used.

  In the bead crushing process, the solvent and the conductive mayenite type compound powder are separated in a short time, and those that cannot be finely pulverized are considered to have poor dispersibility, and can be pulverized without separation, resulting in a conductive mayenite type compound powder. The dispersibility was good. In Table 1, for each example, “good” indicates good dispersibility, and “poor” indicates bad. In the solvent resistance column of Table 1, when the powder was put in each solvent and allowed to stand for 1 day, the conductive mayenite type compound did not change in color and remained green. ◯, the conductive mayenite type compound discolored and turned whitish due to oxidation or hydration was marked with x.

  In the inks prepared in Examples 1 to 17, as shown in Table 1, the alcohol solvent having a hydroxyl group or the amide compound organic solvent having an amino group in Examples 1 to 12 is a dispersibility of the conductive mayenite type compound. It was excellent. On the other hand, the dispersibility was not satisfactory in the organic solvents of Examples 13 to 17 having no hydroxyl group or amino group.

  In addition, when looking at the change in color in each solvent of the conductive mayenite type compound powder, in the alcohol solvent having a hydroxyl group having 3 or more carbon atoms in Examples 1 to 10, the conventional conductive mayenite type compound powder Although the color did not deteriorate, when the methanol or ethanol of Examples 10 and 11 was used as a solvent, the prepared ink was white when left standing for one day. This indicates that the conductive mayenite type compound has lost its conductivity due to oxidation or hydration reaction.

  Further, a field electron emission ink is prepared using ethylene glycol isopropyl ether (boiling point to 142 ° C.) and propylene glycol monomethyl ether (boiling point to 119 ° C.) as a solvent, and this is spin-coated on a conductive substrate to produce a field electron emission device. Was made. Further, this field electron emission device was baked at 200 ° C. for 10 minutes, which is a condition that can prevent oxidation of the conductive mayenite type compound. The number of carbon atoms on the conductive mayenite type compound powder scattered in the obtained field electron emission device was measured by SEM-EDX, and the number of carbon atoms was normalized by the number of calcium atoms for comparison. The number of carbon atoms in the skin of each of the two conductive mayenite type compound powder particles was observed. When propylene glycol monomethyl ether, which has a relatively low boiling point of 119 ° C., is used as an ink solvent, the solvent decomposes and the residual amount of carbon atoms decreases, whereas ethylene having a high boiling point of 142 ° C. It was found that when glycol isopropyl ether was used as a solvent, the residual carbon amount remained about 5 to 8 times as much. When a large amount of carbon remains in this manner, field electron emission from the conductive mayenite type compound may be inhibited. For this reason, it turned out that the boiling point of a solvent is 120 degrees C or less.

(Example 18)
The field electron-emitting device ink D was subjected to suction filtration using filter paper (5A manufactured by Advantech) to obtain a dispersed ink in which particles having an average particle size of 5 μm or less were dispersed. This ink was allowed to stand for one day, and the supernatant was extracted with a dropper to obtain a field electron-emitting device ink E. A part of the ink E was put in a small bottle (1.8141 g), and the weight was measured to find 2.1776 g. When the weight of this small bottle was measured after drying the solvent in a drying furnace, it was 1.8165 g. From this, the weight of the mayenite type compound in the weight of 0.3635 g of the ink E was 0.0024 g, and the content of the conductive mayenite type compound particles was 0.66% by mass.

  For Ink E, the particle size distribution was measured with Microtrac (manufactured by UPA), a particle size distribution measuring device using a dynamic light scattering method. The average particle size of the particles was 0.35 μm, and the standard dispersion was 0. It was found to be a dispersion containing 30 μm particles. The average particle size was found to be the same as the average value calculated from the microtrack when the diameter in terms of a circle was determined for particles in a 5 μm × 5 μm square using a scanning electron microscope.

  About 1 cc of the ink E for field electron-emitting devices was dropped with a dropper on the platinum film surface on a silicon wafer substrate (manufactured by High-Purity Chemical Co., Ltd.) on which a 1.5 cm × 3 cm platinum film was deposited, and at 1000 rpm for 60 seconds. Spin coating was performed (coated substrate E).

  The coated substrate E was placed on a hot plate maintained at 450 ° C. in a nitrogen-filled glove box and heated for 10 minutes. After heating, the hot plate was turned off to allow natural heat dissipation, and when the temperature returned to room temperature, the coated substrate E was taken out of the glove box. The electrode substrate fabricated in this manner was used as a field electron emission device E.

The surface of the field electron emission device E was observed using a scanning electron microscope. The number of particles in a 5 μm × 5 μm square was counted from such a scanning electron microscope image, and the total number was divided by the area to obtain the particle density [number / μm 2 ] on the substrate. As a result, the particle density of the field electron emission device E was 0.40 particles / μm 2 . The circle-equivalent diameter R was determined by dynamic light scattering, and the average particle diameter was 0.35 μm. The threshold voltage characteristics when the obtained field electron emission element E was used in a field emission device were measured.

A field electron emission device as shown in FIG. 1 was used to measure the threshold voltage characteristics. The distance between the conductor thin film 3a formed on the substrate 3 of the field electron emission device and the bottom surface of the anode electrode 2 is adjusted using a glass spacer so as to be 0.1 mm, and is installed in a vacuum vessel. Vacuuming was performed using a turbo molecular pump to a vacuum degree of × 10 −4 Pa or less. The electric field electron device as the cathode electrode is grounded to the bipolar field electron emission device thus formed, and a positive voltage V is applied to the positive electrode using an external power source, and the current flowing between the two electrodes is measured. did. The measured current value was divided by the area of the anode electrode to determine the V dependence of the current density i [μA / cm 2 ]. The results are shown in FIG. The threshold voltage of the field electron emission device comprising the field electron emission element E produced using the field electron emission element ink E produced in Example 1 is very low as 2 V, and the current density i when the applied voltage V is increased. And the electron emission characteristics were excellent.

  The field electron-emitting device ink of the present invention can easily form a field electron-emitting device having good electron-emitting characteristics and excellent dispersibility of conductive mayenite type compound particles, excellent thinness and smoothness. Furthermore, by selecting an appropriate solvent addition amount and a powder concentration of the mayenite type compound, it is possible to provide a field electron emission display device having stable current-voltage characteristics and a large emission current value with a small applied voltage. . If this field electron emission device is used, a field electron emission display device having high-definition pixels can be provided.

1 is a schematic partial cross-sectional view of a bipolar field electron emission device of the present invention. 2 shows field electron emission characteristics of a field electron emission device E according to the present invention.

Explanation of symbols

1: Particle made of conductive mayenite type compound 2: Anode electrode (copper cylindrical electrode)
3: Base body 3a of field emission device: Conductor thin film 4: Cathode electrode

Claims (5)

  1. One of the mayenite type compounds represented by the chemical formula of 12CaO · 7Al 2 O 3 or 12SrO · 7Al 2 O 3 is contained in an amount of 50 mol% or more, and a part of the constituent oxygen of the mayenite type compound is substituted with electrons. Field electron emission characterized by containing 0.01 to 50% by mass of conductive mayenite type compound particles having an electron density of × 10 18 cm −3 or more and 50 to 99.99% by mass of a solvent. Element ink.
  2.   The ink for a field electron emission element according to claim 1, wherein the solvent for the field electron emission element ink is a compound having a hydroxyl group having 3 or more carbon atoms, an amide compound, or a sulfur compound.
  3.   The solvent of the field electron emission element ink is 1-propanol, 2-propanol, 1-butanol, or 2-butanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol isopropyl ether, At least selected from propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol isopropyl ether, 1-hexanol, 1-octanol, 1-pentanol, tert-pentyl alcohol, N-methylformamide, N-methylpyrrolidone, dimethyl sulfoxide It is 1 type, The ink for field electron emission elements of Claim 1 or 2 characterized by the above-mentioned.
  4.   The manufacturing method of the field electron emission element formed by apply | coating the ink for field electron emission elements in any one of Claims 1-3 on a base | substrate.
  5. A field electron emission device comprising: a field electron emission element formed by applying the field electron emission element ink on a substrate surface; and an anode electrode disposed to face the field electron emission element.
JP2006142847A 2006-05-23 2006-05-23 Ink for field electron emission element and method of manufacturing field electron emission element using it Withdrawn JP2007317389A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2006142847A JP2007317389A (en) 2006-05-23 2006-05-23 Ink for field electron emission element and method of manufacturing field electron emission element using it

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2006142847A JP2007317389A (en) 2006-05-23 2006-05-23 Ink for field electron emission element and method of manufacturing field electron emission element using it

Publications (1)

Publication Number Publication Date
JP2007317389A true JP2007317389A (en) 2007-12-06

Family

ID=38851081

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2006142847A Withdrawn JP2007317389A (en) 2006-05-23 2006-05-23 Ink for field electron emission element and method of manufacturing field electron emission element using it

Country Status (1)

Country Link
JP (1) JP2007317389A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007299723A (en) * 2006-04-07 2007-11-15 Asahi Glass Co Ltd Field-electron emitting element
JP2010132467A (en) * 2008-12-02 2010-06-17 Asahi Glass Co Ltd Method for producing oxide
WO2010074092A1 (en) * 2008-12-25 2010-07-01 旭硝子株式会社 High-pressure discharge lamp

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08225393A (en) * 1994-10-31 1996-09-03 At & T Corp Field emission device using improved diamond thin film emitter
JPH1031954A (en) * 1996-07-12 1998-02-03 Futaba Corp Field emitting element and its manufacture
JP2002255528A (en) * 2000-09-18 2002-09-11 Matsushita Electric Ind Co Ltd Fine particle dispersed liquid and its producing method
JP2004276232A (en) * 2003-02-24 2004-10-07 Mitsubishi Electric Corp Carbon nanotube dispersion liquid and method of manufacturing the same
WO2005000741A1 (en) * 2003-06-26 2005-01-06 Japan Science And Technology Agency ELECTROCONDUCTIVE 12CaO·7Al2O3 AND COMPOUND OF SAME TYPE, AND METHOD FOR PREPARATION THEREOF
WO2006112455A1 (en) * 2005-04-18 2006-10-26 Asahi Glass Company, Limited Electron emitter, field emission display unit, cold cathode fluorescent tube, flat type lighting device, and electron emitting material
JP2007037319A (en) * 2005-07-28 2007-02-08 Daikin Ind Ltd Thermoelectronic power generating element
WO2007060890A1 (en) * 2005-11-24 2007-05-31 Japan Science And Technology Agency METALLIC ELECTROCONDUCTIVE 12Cao·7Al2O3 COMPOUND AND PROCESS FOR PRODUCING THE SAME

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08225393A (en) * 1994-10-31 1996-09-03 At & T Corp Field emission device using improved diamond thin film emitter
JPH1031954A (en) * 1996-07-12 1998-02-03 Futaba Corp Field emitting element and its manufacture
JP2002255528A (en) * 2000-09-18 2002-09-11 Matsushita Electric Ind Co Ltd Fine particle dispersed liquid and its producing method
JP2004276232A (en) * 2003-02-24 2004-10-07 Mitsubishi Electric Corp Carbon nanotube dispersion liquid and method of manufacturing the same
WO2005000741A1 (en) * 2003-06-26 2005-01-06 Japan Science And Technology Agency ELECTROCONDUCTIVE 12CaO·7Al2O3 AND COMPOUND OF SAME TYPE, AND METHOD FOR PREPARATION THEREOF
WO2006112455A1 (en) * 2005-04-18 2006-10-26 Asahi Glass Company, Limited Electron emitter, field emission display unit, cold cathode fluorescent tube, flat type lighting device, and electron emitting material
JP2007037319A (en) * 2005-07-28 2007-02-08 Daikin Ind Ltd Thermoelectronic power generating element
WO2007060890A1 (en) * 2005-11-24 2007-05-31 Japan Science And Technology Agency METALLIC ELECTROCONDUCTIVE 12Cao·7Al2O3 COMPOUND AND PROCESS FOR PRODUCING THE SAME

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007299723A (en) * 2006-04-07 2007-11-15 Asahi Glass Co Ltd Field-electron emitting element
JP2010132467A (en) * 2008-12-02 2010-06-17 Asahi Glass Co Ltd Method for producing oxide
WO2010074092A1 (en) * 2008-12-25 2010-07-01 旭硝子株式会社 High-pressure discharge lamp

Similar Documents

Publication Publication Date Title
Kanade et al. Effect of solvents on the synthesis of nano-size zinc oxide and its properties
Jia et al. Efficient field emission from single crystalline indium oxide pyramids
Pan et al. Synthesis and red luminescence of Pr3+-doped CaTiO3 nanophosphor from polymer precursor
KR101037616B1 (en) Phosphor, process for producing the same, lighting fixture and image display unit
Zhang et al. Optical and electrochemical properties of nanosized CuO via thermal decomposition of copper oxalate
Li et al. Recent progress in low-voltage cathodoluminescent materials: synthesis, improvement and emission properties
Vink et al. Enhanced field emission from printed carbon nanotubes by mechanical surface modification
Li et al. Enhanced field emission from injector-like ZnO nanostructures with minimized screening effect
Li et al. Nanotube field electron emission: principles, development, and applications
US6057637A (en) Field emission electron source
Zhi et al. Enhanced field emission from carbon nanotubes by hydrogen plasma treatment
Lee et al. Field emission from well-aligned zinc oxide nanowires grown at low temperature
Pillai et al. The effect of processing conditions on varistors prepared from nanocrystalline ZnO
Li et al. ZnO nanoneedles with tip surface perturbations: Excellent field emitters
Wan et al. Low-field electron emission from tetrapod-like ZnO nanostructures synthesized by rapid evaporation
Warule et al. Organization of cubic CeO 2 nanoparticles on the edges of self assembled tapered ZnO nanorods via a template free one-pot synthesis: significant cathodoluminescence and field emission properties
JP3776911B2 (en) Field emission electron source
Packiyaraj et al. Structural and photoluminescence studies of Eu3+ doped cubic Y2O3 nanophosphors
Kwo et al. Characteristics of flat panel display using carbon nanotubes as electron emitters
US20080248310A1 (en) Carbon nanotube hybrid system using carbide-derived carbon, a method of making the same, an electron emitter comprising the same, and an electron emission device comprising the electron emitter
Devaraju et al. A fast and template free synthesis of Tb: Y2O3 hollow microspheres via supercritical solvothermal method
Vu et al. Photoluminescence and cathodoluminescence properties of Y2O3: Eu nanophosphors prepared by combustion synthesis
Wei et al. Synthesis and field emission of MoO3 nanoflowers by a microwave hydrothermal route
Afanasov et al. Preparation, electrical and thermal properties of new exfoliated graphite-based composites
Lin et al. Sol–gel synthesis and photoluminescent characteristics of Eu3+-doped Gd2O3 nanophosphors

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20090220

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20110316

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20110802

A761 Written withdrawal of application

Free format text: JAPANESE INTERMEDIATE CODE: A761

Effective date: 20110921