JP3199560B2 - Method of manufacturing field emitter array - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a field emitter array, and more particularly, to a method for manufacturing a micro vacuum tube, a display, an electron beam drawing apparatus, an electron beam printer, etc., having good electron emission characteristics and stability. The present invention relates to a method for manufacturing a field emitter array suitable for an electronic device, which can easily manufacture a high-performance field emitter array without difficult operations such as drilling and etching and without complicated operations.

[0002]

2. Description of the Related Art In general, a field emitter array frequently used in the field of electronics is required to have excellent electron emission characteristics and stability. Conventional FEA, silicon, molybdenum, SiC, had been formed by a SiN _4, oxidation resistance, sputtering resistance, on stability is not sufficient, to release the long-term stable electron Had the problem of not being able to do so.

Under these circumstances, US Pat. No. 4,943,720 proposes an emitter in which a conical-shaped point on a steel rod-shaped substrate is coated with a diamond thin film. I have. However, in this case, there is a problem that it is difficult to effectively emit electrons because the point is not sharp. Also, JP-A-4-67
No. 527 proposes a semiconductor electron-emitting device using diamond for a p-type semiconductor layer. this is,
This is an element that emits electrons by avalanche amplification, which is different from a normal element in the principle of electron emission. However, in this case, there is a problem that the crystal structure unique to diamond is not effectively used.

Recently, high-performance electron-emitting devices that solve the above-mentioned problems have been proposed. For example, Japanese Patent Application Laid-Open No. 5-152
Japanese Patent No. 640 discloses a cold cathode emitter element having semiconductor diamond as an emitter and having good electron emission characteristics and the like. In this cold cathode emitter element, a diamond thin film is formed on a silicon substrate, an insulating film is formed, a resist film is coated on the thin film, holes are formed in the resist film by lithography, and etching is performed from above. Then, it is manufactured by peeling and removing the resist and the insulating film in the fine holes. However,
In this case, it is necessary to perform complicated and complicated operations such as drilling and etching, and the manufacturing process becomes complicated and complicated.
There is a problem that an element cannot be obtained efficiently.
Also, there is no description about a method of forming an array.

An object of the present invention is to solve the problems of the prior art. One object of the present invention is to drill a high-performance field emitter array that has good electron emission characteristics and stability and is suitable for electronic devices such as micro vacuum tubes, displays, electron beam drawing apparatuses, and electron beam printers. It is an object of the present invention to provide a method for manufacturing a field emitter array with high performance and stable performance, which can be easily manufactured without performing complicated operations such as difficult control of etching and etching. Further, the object of the present invention can be clarified by documents submitted after filing the present application.

[0006]

In order to solve the above-mentioned problems, the present invention is to form a conductive diamond on a substrate, and then form an insulating film, a resist pattern, and a gate electrode layer in this order. Performing at least once, dissolving and removing the pattern, thereby peeling and removing the gate electrode layer formed on the pattern, and dissolving the exposed insulating film until the diamond is exposed. This is a method for manufacturing a field emitter array.

Hereinafter, a method for manufacturing a field emitter array according to the present invention will be described in detail.

The method for manufacturing a field emitter array according to the present invention includes: 1) an operation of forming diamond with conductivity on a substrate (hereinafter, sometimes referred to as a “diamond forming operation”); and 2) the diamond. Forming an insulating film, a resist pattern, and a gate electrode layer in this order on the substrate on which the forming operation has been performed (hereinafter, may be referred to as a “stacking operation”); and 3) dissolving and removing the pattern. (Hereinafter, also referred to as “gate electrode layer peeling operation”), and 4) the insulation exposed on the substrate on which the peeling operation has been performed. Put the membrane on the diamond
Operation of dissolving and removing until Mondo is exposed (hereinafter may be referred to as "insulating film dissolution operation".) And a.

Hereinafter, each operation will be described.

1) Diamond forming operation In this diamond forming operation, diamond with conductivity is formed on a substrate.

-Substrate-The substrate is not particularly limited in terms of its material, type, specific resistance, size, shape, etc., as long as it can be used as a substrate for semiconductors. It can be appropriately selected within a range that does not harm.

As the material, for example, Si, Ga-
As, SiC, SiO ₂ , Si ₃ N ₄ , SrTiO ₃ ,
Examples include MgO, alumina, AlN, ceramics, sapphire, and cemented carbide. These may be used alone or in combination of two or more.

Among these, Si, SiC, SiO ₂ ,
Si ₃ N _{4 and the} like are preferable. The use of these is advantageous in that the adhesion between the substrate and diamond is good.

The type may be P-type or N-type.
It may be a type.

Preferred examples of the substrate include a p ⁺ silicon wafer (also referred to as a p-type silicon wafer) and quartz (SiO ₂ ).

When the substrate is used as an electrode, the specific resistance is usually 10 ³ Ω · cm or less, preferably 10 ⁻² Ω · cm or less. When diamond itself is used as an electrode, the substrate is preferably an insulator, and its specific resistance is usually 10 ³ Ω · cm or more, preferably 10 ⁵ Ω · cm or more.

-Formation of diamond provided with conductivity- The diamond provided with conductivity has, for example, a specific resistance of usually 10 ³ Ω · cm or less, preferably 10 ² Ω · cm as electrical characteristics. Diamond can be mentioned, and in general, it can be said that there is no particular limitation as long as the diamond has conductivity.
Examples of the diamond imparted with conductivity include diamond exhibiting conductivity without depending on a specific dopant, and semiconductor diamond containing impurities such as a dopant in a diamond crystal. Also. The metallic diamond having the specific resistance of 10 ⁻⁶ Ω · cm or less may be used.

As the diamond exhibiting the conductivity,
A diamond synthesized without intentionally adding a dopant and exhibiting conductivity based on lattice defects can be given. In this case, the specific resistance of the conductive diamond is preferably 10 ⁴ Ω · cm or less. If the specific resistance exceeds 10 ⁴ Ω · cm, the emission current value of the emitter may not be sufficient.

Examples of the semiconductor diamond include a p-type semiconductor diamond and an n-type semiconductor diamond.

The p-type semiconductor diamond is a diamond containing a p-type dopant in the crystal. The p
Examples of the type dopant include boron and the like. To dope boron into diamond, B ₂ O ₃ , boric acid and B ₂ H ₆ are used as boron sources.
Boron compounds such as can be used. Among these boron sources, boron and boron compounds such as B ₂ O ₃ and B ₂ H ₆ are preferred. When doping, one of these can be used alone, or two or more of them can be used in combination.

The content of the p-type dopant in diamond is usually 5 to 10,000 ppm, preferably 10 to 5,000 ppm. If the content is outside the above range, diamond may not show semiconductor properties. On the other hand, if it is within the above range, there is no such case, and if it is 10 to 5,000 ppm,
This is advantageous in terms of diamond crystallinity.

The resistivity of the p-type semiconductor diamond is usually 10 ³ Ω · cm or less.
^-6 to 10 sometimes ² Omega · cm is preferred, in particular, using an insulating substrate, in the case of using the diamond as an electrode may also be preferable 10 ^-6 ~10 ^-2 Ω · cm.

The n-type semiconductor diamond is a diamond containing an n-type dopant in the crystal. The n
Examples of the type dopant include phosphorus and sodium. Of these, phosphorus is preferred. To dope phosphorus into diamond, a phosphorus compound such as phosphoric acid, P ₂ O ₅ , PH ₃ , preferably P
Phosphorus compounds such as ₂ O ₅ and PH ₃ can be used. These phosphorus compounds can be used alone or in combination of two or more. The n-type dopant contained in the n-type semiconductor diamond may be one kind, for example, only phosphorus, or may be a different kind of dopant.

The content of the n-type dopant in diamond is usually 5 to 10,000 ppm, preferably 10 to 5,000 ppm. If the content is outside the above range, diamond may not show semiconductor properties. On the other hand, if it is within the above range, there is no such case, and if it is 10 to 5,000 ppm,
This is advantageous in terms of diamond crystallinity.

The specific resistance of the n-type semiconductor diamond is usually 10 ³ Ω · cm or less.
^-6 to 10 sometimes ² Omega · cm is preferred, in particular, using an insulating substrate, in the case of using the diamond as an electrode is preferably 10 ^-6 ~10 ^-2 Ω · cm.

In the present invention, a single layer of the p-type or n-type semiconductor diamond may be formed on the substrate, or a single layer of the p-type semiconductor diamond and the layer of the n-type semiconductor diamond may be formed. Multiple layers may be formed.

The p-type or n-type semiconductor layer first formed on the substrate, whether it is a single layer of a p-type or n-type semiconductor diamond or a plurality of layers of a p-type semiconductor diamond layer and the n-type semiconductor diamond layer The thickness of the semiconductor diamond is usually 0.1 to 10 μm, preferably 0.1 to 10 μm.
5 to 5 μm. If the thickness is outside the range, the electron emission characteristics of the field emitter array may not be sufficient. On the other hand, when the thickness is 0.1 to 10 μm, such a phenomenon does not occur. When the thickness is 0.5 to 5 μm, it is advantageous in that a field emitter array having good electron emission characteristics can be manufactured.

In the case of the plurality of layers, the combination of the n-type semiconductor diamond layer and the p-type semiconductor diamond layer is not particularly limited, and the p-type semiconductor diamond and the n-type semiconductor diamond are alternately formed on the substrate. And a plurality of layers. For example, p
It is also possible to form two layers of a type semiconductor diamond and an n-type semiconductor diamond one by one in this order or vice versa, or to further form a p-type semiconductor diamond or an n-type semiconductor diamond thereon. Three layers may be used. Further, four or more layers may be provided. The number of layers is usually 2 to 6 layers, preferably 2 to 4 layers. The thickness of the second and subsequent diamond layers is usually 10 to 10 μm, preferably 100 to 1 μm.
m. If the thickness exceeds 10 μm, there is no effect corresponding thereto, while if it is less than 10 °, there may be no merit of multilayering. If the number of layers is out of the range, the electron emission characteristics of the field emitter array may not be sufficient. On the other hand, this is not the case when it is within the above range, and it is particularly advantageous to use two to four layers, since a field emitter array having good electron emission characteristics can be manufactured.

In the present invention, the diamond having conductivity provided on the substrate, for example, a p-type semiconductor diamond, may be in the form of particles instead of a film. In the case of forming the particles of the p-type semiconductor diamond, Si is preferable as the material of the substrate, and preferable examples are p ⁺ -type silicon wafer and n ⁺
Mold silicon wafer. This is advantageous in that a field emitter array having excellent adhesion between the substrate and diamond, electron emission characteristics, and the like can be manufactured.

The average particle diameter of the conductive diamond particles is, for example, usually 0.1 to 10 μm.
And preferably 0.5 to 5 μm. If the average particle size is outside the above range, the electron emission characteristics of the field emitter array may not be sufficient. On the other hand, this is not the case within the above range, and if it is 0.1 to 10 μm, a field emitter array having sufficient electron emission characteristics can be manufactured.

The diamond provided with conductivity is:
Usually, it is formed on the entire surface of the substrate, but may be formed only on a part of the substrate depending on the purpose.

The formation of the diamond with conductivity can be performed by, for example, a known method of forming a semiconductor diamond. Specifically, it can be carried out by a known gas phase synthesis method using a dopant gas and a carbon source gas.

As the above-mentioned vapor phase synthesis method, for example, CVD
, PVD, PCVD or a combination thereof. Among them, usually, various hot filament methods including EACVD method, various direct current plasma CVD methods including thermal plasma method, microwave plasma CVD methods including thermal plasma method, and the like are preferable, and particularly, microwave plasma CVD method. The method is preferred. The microwave plasma CVD method is advantageous in that diamond with conductivity can be formed economically and easily. The dopant gas can be obtained, for example, by heating a solid dopant and reacting it with a hydrogen plasma gas.

[0034] Examples of the solid dopant include an n-type dopant and a p-type dopant.

The n-type dopant and the p-type dopant are as described above.

The temperature of the solid dopant is appropriately determined according to the type of the solid dopant.
The temperature is appropriately determined usually from the room to the boiling point of the solid dopant, preferably from room temperature to the melting point of the solid dopant.

When hydrogen gas is supplied under the temperature environment,
The hydrogen gas is turned into plasma, becomes a hydrogen plasma gas, and reacts with the solid dopant. As a result, a dopant gas is generated.

The supply amount of the hydrogen gas varies depending on the size of the reactor and cannot be specified unconditionally, but is usually from 1 to 1,000 sccm.

The thus obtained dopant gas is mixed with carbon plasma and reacted under predetermined conditions, whereby diamond with conductivity can be formed on the substrate.

The carbon plasma can be obtained by exciting a carbon source gas by a method known per se.

Examples of the carbon source gas include paraffinic hydrocarbons such as methane, ethane, propane and butane; olefinic hydrocarbons such as ethylene, propylene and butylene; acetylenic hydrocarbons such as acetylene and allylene; butadiene and allene Diolefin hydrocarbons such as cyclopropane, cyclobutane, cyclopentane,
Alicyclic hydrocarbons such as cyclohexane; aromatic hydrocarbons such as cyclobutadiene, benzene, toluene, xylene and naphthalene; ketones such as acetone, diethyl ketone and benzophenone; alcohols such as methanol and ethanol; Hydrocarbon; trimethylamine,
Amines such as triethylamine; other nitrogen-containing hydrocarbons; carbon dioxide, carbon monoxide, and carbon peroxide.

Among them, paraffinic hydrocarbons such as methane, ethane, and propane; alcohols such as ethanol and methanol; ketones such as acetone and benzophenone; amines such as trimethylamine and triethylamine; carbon dioxide; Are preferable, and carbon monoxide and methane are particularly preferable. These may be used alone or in a combination of two or more.

The carbon source gas may be an active gas such as hydrogen,
It may be used by mixing with a carrier gas of an inert gas such as helium, argon, neon, xenon, and nitrogen.

When a mixed gas of a carrier gas and a carbon source gas is used, the carbon source gas is methane gas (CH
₄ ) When methane gas content is 5 mol%
It is preferably less than.

When carbon monoxide is used as the carbon source gas, it is preferable to use hydrogen gas as the carrier gas. The use of a mixed gas of carbon monoxide and hydrogen gas is advantageous in that the growth rate of diamond with conductivity can be increased. For example, under the same conditions, a growth rate of diamond with conductivity that is 2 to 10 times that of a source gas obtained by combining methane and hydrogen gas may be obtained.

The carbon monoxide is not particularly limited. For example, it is possible to use a product obtained by sufficiently reacting a furnace gas or a water gas obtained by hot-reacting coal or coke with air or steam. it can. The hydrogen gas is not particularly limited, and may be obtained by gasification of petroleum, conversion of natural gas, water gas, etc., electrolysis of water, reaction between iron and steam, complete gasification of coal, and the like. Can be used.

When the hydrogen gas and carbon monoxide are used in combination, the content of the carbon monoxide gas is usually 1 to 80 mol%, preferably 5 to 60 mol%, and more preferably 10 to 60 mol%. 60 mol% is preferred. If the content of the carbon monoxide gas is less than 1 mol%, a sufficient growth rate of a thin film-like conductive diamond may not be obtained. On the other hand, if it exceeds 80 mol%, the purity of the diamond component in the deposited diamond with conductivity may decrease. On the other hand, if it is within the above range, such a case does not occur.
This is advantageous in that the synthesis rate and crystallinity are good.

The predetermined conditions include pressure, temperature, time and the like.

The pressure is usually 10 ⁻⁶ to 10 ³ T
orr, preferably 1 to 760 Torr,
Particularly, 1 to 500 Torr is preferable. If the pressure is outside the above range, the formation rate of diamond with conductivity may not be sufficient. On the other hand, if it is within the above range, such a case does not occur. When the pressure is 1 to 760 Torr, the formation rate of the diamond to which conductivity is given is large, which is preferable. Is advantageous in terms of stability.

The temperature is usually room temperature to 1,200 ° C., preferably room temperature to 1,100 ° C., based on the surface temperature of the substrate. If the temperature is outside the above range, diamond with conductivity may not be sufficiently formed. On the other hand, when the temperature is within the above range, such a case does not occur and the temperature is from room temperature to 1,100
C is advantageous in that diamond having crystallinity and conductivity can be formed at high speed without etching.

The reaction time is not particularly limited.
It can be appropriately selected so as to obtain a diamond having a desired thickness and conductivity. Usually 10
Minutes to 200 hours.

2) Lamination Operation In this lamination operation, an insulating film, a resist pattern, and a gate electrode layer are formed in this order on the substrate on which the diamond forming operation has been performed.

-Formation of Insulating Film- The insulating film is a film made of an insulating material.
As the insulating material, for example, SiO ₂ , Hf O
₂ , ZrO ₂ , Si ₃ N ₄ , polyimide, alumina, Y
₂ O _{3 and the} like can be mentioned. Among these, S
iO ₂ and Hf O ₂ are preferred. These cases are advantageous in terms of withstand voltage. These may be used alone to form the insulating film, or two or more of them may be used in combination to form the insulating film. In the present invention, these commercially available paints can also be used.

The insulating film is preferably a film having no pinholes or the like. When pinholes exist,
May not work as an emitter.

The specific resistance of the insulating film is usually 10 ³
It is larger than Ω · cm, preferably 10 ⁴ Ω · cm or more. If the specific resistance is out of the above range, the life of the emitter element may be shortened, or the emitter element may be short-circuited and easily broken down when a high voltage is applied.
On the other hand, there is no such a case within the above range, and 10
^{When it is 4} Ω · cm or more, it is advantageous in manufacturing because it has electrical resistance even if it is thin.

The thickness of the insulating film is not particularly limited as long as it is a thickness sufficient to flatten the substrate, but is usually 1,000 ° or more, preferably 0.1 to 10 μm.
And particularly preferably 0.2 to 5 μm. If the thickness is less than 1,000 °, dielectric breakdown may easily occur. On the other hand, if the thickness is within the above range, such a situation does not occur.
If it is μm, it is more advantageous in terms of dielectric breakdown resistance and the magnitude of an applied electric field.

The withstand voltage of the insulating film is usually 10
⁵ V / m or more, preferably 10 ⁶ V / m or more, particularly preferably 10 ⁷ V / m or more. If the withstand voltage is less than the above range, dielectric breakdown is likely to occur. On the other hand, if it is within the above range, such a phenomenon does not occur and 10 ⁷
When it is V / m or more, a high voltage can be applied to the emitter, which is advantageous in that the current value can be increased.

The insulating film can be formed by a method known per se. For example, the insulating material is
It can be formed by coating on the substrate by a coating method and drying, or by vapor deposition on the substrate by a vapor deposition method. As described above, the insulating film 4 can be formed on the diamond 3 formed on the surface of the substrate 2 as shown in FIG.

-Formation of Pattern with Resist- To form a pattern with the resist, a lithography technique known per se can be used. Specifically, a resist is applied on the substrate on which the diamond forming operation has been performed, and dried. Next, the applied resist is exposed to light such as ultraviolet rays through a photoplate having a light-shielding portion having a pattern of a desired shape or a pattern reverse thereto. Then, by removing the exposed or unexposed portions using a developing solution, a rinsing solution, a solvent, or the like,
A desired pattern made of a resist can be selectively formed on the substrate.

Examples of the resist include, for example, resists for electron beams and X-rays in addition to photoresists.

Examples of the photoresist include a positive photoresist and a negative photoresist. As these resists, various known resin-based or rubber-based photoresists can be used in addition to those generally used.

Commercially available positive photoresists include OFPR-2 and OFPR- manufactured by Tokyo Ohka Kogyo Co., Ltd.
800 and the like. Commercially available negative photoresists include, for example, LMR-33 manufactured by Fuji Pharma Co., Ltd. and OM manufactured by Tokyo Ohka Kogyo Co., Ltd.
R-83, OMR-85 and the like can be mentioned.

The application of the resist can be carried out by using, for example, a method such as spraying, spinner, dipping, or brushing. Among these, it is preferable to use a spinner. This case is advantageous in that the operation is simple and uniform coating can be performed.

The thickness of the resist to be applied is not particularly limited, but is usually 0.1 to 10 μm, preferably 0.5 to 5 μm, and particularly preferably 0.5 to 3 μm. If the thickness is out of the range, a desired pattern may not be easily obtained. On the other hand, when the thickness is within the above range, such a phenomenon does not occur. When the thickness is 0.5 to 5 μm, the gate electrode layer formed on the surface can be easily peeled off at the time of lift-off. When it is 5 to 3 μm, it is advantageous in terms of shortening the exposure time and resolution.

Examples of the exposure system include a contact exposure system, a proximity exposure system, and a projection exposure system. These can be appropriately selected according to the purpose.

The developer, rinsing solution, solvent and the like are not particularly limited, and those known per se can be used, and commercially available products may be used.

The pattern is not particularly limited in its shape, size, number, interval, etc., and can be appropriately selected according to the purpose.

Examples of the shape include a circle such as a perfect circle and an ellipse, a rectangle such as an equilateral triangle, a square, and a band, and a polygon such as a hexagon. Among these,
A circle, square, band, or the like is preferable. These cases are advantageous in that the gate electrode can be easily peeled and removed in the same shape as the pattern.

As the size, the diameter is usually 0.5
It is 10 μm to 10 mm, preferably 1 μm to 1 mm. The diameter means a diameter or a long diameter for a circular pattern, and means the largest diameter among diameters passing through the center of a polygonal pattern. In the case of a band, it means a line width. If the size is outside the range, it may be difficult to form a field emitter array. On the other hand, this is not the case within the above range, and when it is 1 μm to 1 mm, lift-off can be easily performed, which is advantageous in forming a field emitter array.

The number can be appropriately selected according to the size of the substrate and the like, but is usually 2 or more, preferably 4 or more. If the number is one, if one of them is defective, it may not operate as an emitter. On the other hand, if it is within the above range, there is no such problem. If the number is four or more, even if some of them are defective, the remaining emitters operate, so that the function as an emitter is lost as a whole. This is advantageous in that the possibility of doing so can be reduced.

The interval means an interval between adjacent patterns and can be appropriately selected according to the size of the substrate and the like, but is usually 0.5 μm to 10 mm, preferably 1 μm to 1 mm. It is. The interval is 1μ
If it is less than m, separation between the emitters cannot be performed, and 1
Even if it exceeds 0 mm, the effect corresponding thereto cannot be obtained, and it may be too large for packaging. On the other hand, if it is within the above range, there is no such thing,
When it is 1 μm to 1 mm, it is advantageous in that the field emitter array is easily manufactured in the process.

As described above, as shown in FIG. 6, a pattern 6 of a resist can be further formed on the insulating film 4 on the substrate 2 on which the diamond 3 and the insulating film 4 are formed in this order.

-Formation of Gate Electrode Layer- The gate electrode layer can be formed by a film forming method known per se, usually using a material constituting a gate electrode.

As a material constituting the gate electrode,
For example, Al, Au, Pt, Ti, Cr, Mo, W and the like can be mentioned. Among these, W, Mo, Al
Is preferred. Use of these is advantageous because a field emitter array having good electron emission characteristics can be obtained.

Examples of the film forming method include a sputtering film forming method, a vacuum evaporation method, an ion plating method, and a plasma CVD method. Among these, the sputtering film forming method is preferable. These are preferred in that the gate electrode layer can be easily formed by a simple operation.

The thickness of the gate electrode layer is usually 5
00Å-100 μm, preferably 1,000Å
10 μm, and particularly preferably 3,000 ° to 5 μm. If the thickness is outside the above range, the effect of forming the gate electrode layer may not be sufficient. On the other hand, if the thickness is within the above range, such a phenomenon does not occur. If the thickness is 1,000 ° or more, a uniform and pinhole-free film can be synthesized. Can be advantageously performed.

As described above, as shown in FIG. 5, the gate electrode layer 5 is formed on the insulating film 4 and the resist pattern 6 on the substrate 2 on which the diamond 3, the insulating film 4 and the resist pattern 6 are formed in this order. can do.

3) Gate electrode layer peeling operation In this gate electrode layer peeling operation, the pattern formed in the laminating operation is dissolved and removed to peel off the gate electrode layer formed on the pattern.

The peeling of the pattern can be carried out using an appropriately selected pattern solution. As the pattern dissolving solution, for example, a dissolving solution for the resist can be suitably mentioned. A commercially available product may be used as the resist solution.

The pattern dissolving solution penetrates through the fine holes existing only in the portion of the gate electrode layer on the peripheral side surface of the pattern formed therebelow to dissolve the pattern. When the pattern is dissolved, the gate electrode layer formed on the surface is easily separated from the substrate.

As described above, as shown in FIG. 4, the resist pattern 6 in FIG. 5 and the gate electrode layer 5 formed on the surface thereof can be removed. The film 4 can be exposed.

4) Insulating Film Dissolving Operation In this insulating film dissolving operation, the insulating film exposed on the substrate on which the gate electrode layer peeling operation was performed is removed by the diamond
Dissolve and remove until the mond is exposed .

For the dissolution and removal, for example, in the case of SiO ₂ , buffered hydrofluoric acid or an aqueous HF solution can be used. Among these, buffered hydrofluoric acid is preferred. In these cases, the insulating film can be dissolved in a short time, which is advantageous in that the handling is easy.

The time for the dissolution and removal can be appropriately selected according to the thickness of the insulating film, the size of the pattern, and the like. The time is preferably set so that the dissolving and removing operation is completed when the diamond is exposed.

As described above, as shown in FIG. 1, in FIG. 4, the insulating film 4 exposed on the surface is dissolved, the diamond 2 formed thereunder is exposed on the surface, and the field emitter array 1 having a bipolar structure is formed. Can be manufactured.
When this field emitter array 1 is viewed from above, FIG.
As shown in the figure, the diamond 3 is exposed from an opening having the same shape as the resist pattern 6 formed at a predetermined position in the gate electrode layer 3.

In the present invention, the above-mentioned laminating operation can be performed twice or more to form a field emitter array having a multilayer structure. In this case, after the second time, the step of forming the pattern using the resist can be omitted. Thereafter, by dissolving the resist, all of the insulating film and the gate electrode layer laminated on the pattern can be removed.

When the laminating operation or the process is performed once, a field emitter array having a bipolar structure as shown in FIG. 1 can be manufactured. When the laminating operation or the process is performed twice, as shown in FIG. A field emitter array having such a three-pole structure can be manufactured. Therefore, if the lamination operation or the process is performed n times, a field emitter array having an (n + 1) pole structure can be manufactured.

The number of times of the laminating operation or the step is usually 1 to 10, preferably 1 to 5, and particularly preferably 1 to 3. When the number of times is out of the range,
In some cases, the field emitter array cannot be manufactured efficiently. A field emitter array in which the number of times is three or less and up to a quadrupole structure is practically convenient.
The number of times can be appropriately determined depending on the type of the target field emitter array.

As described above, a high-performance field emitter array can be easily, simply, and efficiently manufactured without performing difficult operations such as drilling and etching. The resulting field emitter array is
It has high electron emission characteristics, has sufficient oxidation resistance, sputtering resistance, and stability, and can stably emit electrons for a long period of time. Therefore, it can be suitably used in a wide field including an electronic device field such as a display, an electron beam drawing apparatus, a micro vacuum tube, and an electron beam printer.

[0090]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments and comparative examples of a method for manufacturing a field emitter array according to the present invention will be described below. The present invention is not limited by these.

(Example 1) 1) Diamond forming operation A 12 mm square p-type silicon wafer was used as a substrate. By microwave plasma CVD (2.45 GHz), CO / H ₂ is used as a source gas at 10/90 sc each.
cm 2, using a p-type dopant, B ₂ H ₆ , as a dopant so that the ratio of boron to carbon in the source gas becomes 1000 ppm, under the conditions of a reaction pressure of 40 Torr and a substrate temperature of 900 ° C. By reacting for 2 hours, a layer of p-type diamond was formed on the substrate.

2) Laminating Operation A coating of SiO ₂ (OCD type-7, manufactured by Tokyo Ohka Kogyo Co., Ltd.) is applied on the p-type semiconductor diamond layer on the substrate on which the diamond forming operation has been performed, and dried. Then, an insulating film made of SiO _{2 having} a thickness of 0.6 μm was formed.

Next, a positive photoresist (OFPR-800, manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied on the insulating film to a thickness of about 1 μm using a spin coater. Prebaking was performed at 85 ° C. for 30 minutes. Thereafter, a photomask having 100 × 100 circular light-shielding portions having a diameter of 5 μm at intervals of 15 μm is arranged on the application surface, and the coating is performed using a resist aligner (PLA-501FA manufactured by Canon Sales Co., Ltd.). The surface was exposed (13 mW / cm ² ) for 3 seconds. After the exposure, development was performed for 60 seconds with a developer NMD-3 manufactured by Tokyo Ohka Kogyo Co., Ltd.
After rinsing with pure water, the exposed portion of the positive photoresist was removed, and the substrate was heated at 135 ° C. for 30 minutes to form a resist pattern.

Thereafter, a gate electrode layer made of tungsten having a thickness of 5,000.degree. Was formed by sputtering on the pattern made of the resist and the exposed insulating film.

3) Stripping operation of the gate electrode layer The resist pattern was formed using a dedicated stripper.
After dissolution, the gate electrode layer formed on the pattern was peeled off.

4) Dissolution operation of insulating film The buffered hydrofluoric acid was brought into contact with the substrate after the gate electrode layer peeling operation, and the exposed insulating film was dissolved and removed.

The field emitter array was manufactured as described above, and the characteristics of the obtained field emitter array were evaluated as follows. Between the substrate and the gate electrode layer in the field emitter array,
+300 V was applied such that the gate electrode layer side became positive. As a result, a current of 5 mA was obtained.

Example 2 In Example 1, the p-type dopant B ₂ H ₆ was used as the dopant, and the ratio of boron to carbon in the source gas was 1,000.
Instead of having been set to be ppm, the formation of diamond was performed for 2 hours by using PH ₃ which is an n-type dopant as a dopant, and the ratio of phosphorus to carbon in the raw material gas was set to 100 ppm. B ₂ H ₆ which is a p-type dopant is used as a dopant, and the ratio of boron to carbon in the raw material gas is 1,000.
A field emitter array was manufactured in the same manner as in Example 1 except that the diamond formation was performed at 15 ppm for 15 minutes, and the same evaluation was performed on the obtained field emitter array. As a result, a current of 15 mA was obtained.

Comparative Example 1 A field emitter array was manufactured in the same manner as in Example 1 except that the diamond forming operation was not performed, and the same evaluation was performed on the obtained field emitter array. . As a result, a current of only 10 ⁻⁹ Å or less was obtained.

(Comparative Example 2) The same operation as in Example 1 was performed except that one emitter was manufactured without forming an array. The resulting emitter buzz was about 50%. In addition, about half, the emission was below the noise level. The current value of the observed emission was about 0.6 mA.

[0101]

The present invention provides a high-performance field emitter array having good electron emission characteristics and stability and suitable for electronic devices such as a micro vacuum tube, a display, an electron beam drawing apparatus, and an electron beam printer. It is possible to provide a method for manufacturing a field emitter array which can be easily manufactured without performing complicated operations such as difficult control of perforation and etching.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a bipolar field emitter array manufactured by a method of manufacturing a field emitter array according to the present invention.

FIG. 2 is a schematic explanatory view of the field emitter array having the bipolar structure shown in FIG. 1 as viewed from above.

FIG. 3 is a schematic sectional view showing an example of a field emitter array having a three-pole structure manufactured by the method for manufacturing a field emitter array according to the present invention.

FIG. 4 is a schematic cross-sectional view showing an example of a state in which a pattern made of a photoresist is dissolved and removed to peel off and remove the gate electrode layer formed on the pattern.

FIG. 5 is a schematic cross-sectional view showing an example of a state in which a pattern made of diamond, an insulating film, a photoresist, and a gate electrode layer are formed in this order on a substrate.

FIG. 6 is a schematic cross-sectional explanatory view showing an example of a state in which a diamond, an insulating film, and a pattern made of a photoresist are formed in this order on a substrate.

FIG. 7 is a schematic sectional view showing an example of a state in which diamond and an insulating film are formed in this order on a substrate.

[Description of sign]

DESCRIPTION OF SYMBOLS 1 ... Field emitter array, 2 ... Substrate, 3
... diamond, 4 ... insulating film, 5 ... gate electrode layer, 6 ... pattern by photoresist,

Claims (5)

(57) [Claims] After forming diamond with conductivity on a substrate, a step of forming a pattern of an insulating film, a resist, and a gate electrode layer in this order is performed at least once, and the pattern is dissolved and removed. And removing the gate electrode layer formed on the pattern by stripping and removing the exposed insulating film until the diamond is exposed . 2. After forming diamond with conductivity on a substrate, a pattern of an insulating film and a resist and a gate electrode layer are formed in this order, and the pattern is dissolved and removed to form a pattern on the pattern. Performing the step of peeling and removing the gate electrode layer formed at least once to expose the insulating film to which the diamond is exposed.
A method for manufacturing a field emitter array, wherein the field emitter array is dissolved and removed. 3. The method according to claim 1, wherein said diamond is a single layer of p-type or n-type diamond or a plurality of layers having a p-type diamond layer and an n-type diamond layer. . 4. The method according to claim 1, wherein the diamond has an average particle size of 0.1.
3. The method for manufacturing a field emitter array according to claim 1, wherein the particles are p-type diamond particles of 10 to 10 [mu] m. Wherein said field emitter array, any of the preceding claims having two or more emitters 1
13. The method for manufacturing a field emitter array according to any one of the above items .