JP2009245672A - Field emission device and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a field emission device or the like which emits electrons by concentrating them in an electric field efficiently, and achieves high emission electric current density at a low driving voltage. <P>SOLUTION: The field emission device 101 includes a cathode layer 102 consisting of a conductor, an insulating layer 103 arranged on the cathode layer, a gate layer 104 arranged on the insulating layer 103, and composed of the conductor in which a slit 106 is arranged, and an emitter 105. At the insulating layer 103, a gap from the slit 106 to the opposing region 108 opposing to the slit 106 in the cathode layer 102 is arranged, and the emitter 105 is composed of a structure having a plurality of thorn-shaped protruded ends which are arranged on the opposing region 108, and typically in which a single layer and three layers of thin carbon nano tubes are entangled. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a field emission device suitable for efficiently emitting an electron by concentrating an electric field and realizing a high emission current density with a low driving voltage, and a manufacturing method thereof.

Conventionally, various electronic devices using carbon nanotubes have been proposed. Such a technique is disclosed in the following document, for example.
JP 2006-035379 A

  Here, [Patent Document 1] discloses a technique in which a mask having a hole is placed on a substrate, a catalytic substance is supplied and supported on the substrate, and carbon nanotubes are grown therefrom. .

  Here, it is considered that a field emission device can be formed by using a conductor with a hole as a gate layer, a substrate as a conductor as a cathode layer, and a carbon nanotube as an emitter.

  Conventionally, in a field emission device using carbon nanotubes, in order to support the carbon nanotubes themselves, it has been common to increase the diameter.

  However, when thick carbon nanotubes are used as emitters, the degree of electric field concentration is reduced, driving voltage is increased, the mounting density of carbon nanotubes as emitters is low, and the amount of current per carbon nanotube increases. The possibility that the carbon nanotube itself will be destroyed becomes high, and it will fall into the vicious circle that the carbon nanotube must be made thicker.

  On the other hand, in the technique disclosed in [Patent Document 1], since thin carbon nanotubes can be formed, electric field concentration can be caused efficiently, but the amount of electrons emitted from the emitter is often small.

  Thus, there is a strong demand for using as many carbon nanotubes as possible to efficiently concentrate the electric field while at the same time increasing the amount of electrons emitted.

  The present invention solves the problems as described above, and efficiently discharges electrons by concentrating the electric field, and is suitable for realizing a high emission current density with a low driving voltage, and a field emission device, It aims at providing the manufacturing method.

  A field emission device according to a first aspect of the present invention includes a cathode layer made of a conductor, an insulating layer arranged on the cathode layer, and a gate layer made of a conductor arranged on the insulating layer and provided with a slit. And an emitter, which are configured as follows.

  That is, the insulating layer is provided with a gap from the slit to a facing region facing the slit in the cathode layer.

  On the other hand, the emitter is composed of a structure in which a plurality of carbon nanotubes arranged on the facing region are intertwined.

  In the field emission device of the present invention, some or all of the plurality of carbon nanotubes extend from the facing region toward the slit, and the general shape of the structure is a mountain range, a brush shape, a tree shape Alternatively, it can be configured to have a grass belt shape.

  In the field emission device of the present invention, the carbon nanotube can be configured to be a single-walled carbon nanotube, a double-walled carbon nanotube, or a three-walled carbon nanotube.

In the field emission device of the present invention, the slit has a width of 0.1 μm to 3 μm, the slit has a length of 10 μm to 500 μm, and the insulating layer has a thickness of 0.03 μm to 10 μm. The diameter of the carbon nanotubes is 0.4 nm to 10 nm, and the number density of the carbon nanotubes on the facing region is 10 ^{2 to} 10 ⁵ per 1 μm ^2. it can.

  In the field emission device of the present invention, a plurality of the slits may be provided in parallel, and the interval between the plurality of slits may be 1 μm to 1000 μm.

  The field emission device of the present invention further includes a catalyst layer that promotes the growth of the carbon nanotubes between the emitter and the cathode layer, in order to suppress alloying of the catalyst layer and the cathode layer. The catalyst carrier layer that supports the catalyst layer can be further provided.

  The field emission device of the present invention can be configured as follows.

That is, the cathode layer is made of Mo, W, Ta, MoW, MoTa, Cr, other metals or alloys, TaSi _x , MoSi _x , WSi _x , CrSi _x , other metal silicides, TiN, TaN, other metal nitrides , N-type or p-type doped polycrystalline silicon, or a laminated structure of these and Al or Cu, or a cladding structure of Al or Cu.

On the other hand, the gate layer is made of Mo, W, Ta, MoW, MoTa, Cr, other metals or alloys, TaSi _x , MoSi _x , WSi _x , CrSi _x , other metal silicides, TiN, TaN, other metal nitrides It is formed by a single layer structure, or a laminated structure in which a part of n-type or p-type doped polycrystalline silicon is silicided.

  Further, the catalyst carrier layer is formed of a substance containing one or more elements of Si, Al, Mg, O, N, and C.

  The catalyst layer is formed of cobalt, iron, nickel, molybdenum, or a mixture containing these.

On the other hand, the insulating layer is formed by a single layer structure of SiO _x , SiO _x N _y , or SiN _x or a laminated structure thereof.

  A field emission device manufacturing method according to another aspect of the present invention includes a cathode layer film forming step, an insulating layer film forming step, a gate layer film forming step, a slit step, a gap step, and an emitter forming step as follows. Constitute.

  That is, in the cathode layer film forming step, a cathode layer made of a conductor is formed on the substrate.

  On the other hand, in the insulating layer film forming step, an insulating layer made of an insulator is formed on the formed cathode layer.

  Further, in the gate layer forming step, a gate layer made of a conductor is formed on the formed insulating layer.

  In the slit process, a slit is provided in the formed gate layer.

  On the other hand, in the gap step, the gap is provided by removing the insulating layer so that the facing region of the cathode layer facing the slit is exposed through the provided slit.

  Further, in the emitter forming step, an emitter made of a structure in which a plurality of carbon nanotubes are entangled is formed on the facing region.

  In the field emission device manufacturing method of the present invention, in the emitter forming step, part or all of the plurality of carbon nanotubes are extended from the facing region toward the slit, and the outline of the structure is , Brush shape, tree line shape, or lawn belt shape.

  In the field emission device manufacturing method of the present invention, the carbon nanotube is formed by a chemical vapor deposition method for supplying carbon, and the carbon nanotube is a single-walled carbon nanotube, a double-walled carbon nanotube, or a three-layered carbon nanotube. It can be configured to set the supply concentration and supply time of the carbon source so as to be a carbon nanotube.

In the method for manufacturing a field emission device of the present invention, the width of the slit is 0.1 μm to 3 μm, the length of the slit is 10 μm to 500 μm, and the thickness of the insulating layer is 0.1 μm. The diameter of the carbon nanotube is 0.4 nm to 10 nm, and the number density of the carbon nanotube on the facing region is 10 ^{2 to} 10 ⁵ per 1 μm ^2. can do.

  In the field emission device manufacturing method of the present invention, a plurality of the slits may be provided in parallel, and the interval between the plurality of slits may be 1 μm to 1000 μm.

  In the field emission device manufacturing method of the present invention, the slit is formed by forming a resist layer on the gate layer, and forming a slit in the resist layer by lithography, stamping, scratching, or crack formation, The gate layer can be formed by etching through the slit.

  Moreover, the manufacturing method of the field emission apparatus of this invention is further equipped with the catalyst support layer process and the catalyst layer process, and can be comprised as follows.

  That is, in the catalyst carrier layer step, after the facing region is exposed, a catalyst carrier layer is formed on the facing region through the slit.

  On the other hand, in the catalyst layer step, a catalyst layer that promotes the growth of the carbon nanotubes is formed on the catalyst carrier layer through the slit, and is supported on the catalyst carrier layer.

  In this way, the catalyst carrier layer is prevented from alloying with the catalyst layer and the cathode layer.

  In the method for manufacturing a field emission device of the present invention, the cathode layer and the gate layer are formed by a sputtering method for supplying molybdenum, and the catalyst carrier layer is formed by a sputtering method for supplying aluminum oxide. The layer can be formed by a sputtering method for supplying cobalt, and the insulating layer can be formed by a chemical vapor deposition method for supplying silicon oxide.

  According to the present invention, it is possible to provide a field emission device and a method for manufacturing the field emission device that are suitable for efficiently concentrating an electric field to emit electrons and realizing a high emission current density with a low driving voltage. .

  Embodiments of the present invention will be described below. The embodiments described below are for explanation, and do not limit the scope of the present invention. Therefore, those skilled in the art can employ embodiments in which each or all of these elements are replaced with equivalent ones, and these embodiments are also included in the scope of the present invention.

  FIG. 1 is a perspective view showing a state of a field emission device according to one embodiment of the present invention, and FIG. 2 is a cross-sectional view of the field emission device. Hereinafter, description will be given with reference to these drawings.

  As shown in these drawings, the field emission device 101 includes a cathode layer 102, an insulating layer 103, a gate layer 104, and an emitter 105.

  The cathode layer 102 and the gate layer 104 have a shape of a thin film flat plate made of a conductor such as molybdenum, and an insulating layer 103 made of an insulator such as silicon oxide is sandwiched therebetween.

  When molybdenum or the like is used as the cathode layer 102, a conductive thin film is generally formed on a substrate 121 such as a silicon substrate with an oxide film or a glass plate. It is also possible to use a doped silicon substrate itself having properties.

  A slit 106 is provided in the gate layer 104, and a gap 107 is provided in the insulating layer 103 from the slit 106 to the cathode layer 102.

  In general, the shape of the air gap 107 is depicted as a slope in the figure for the sake of easy understanding (the same applies hereinafter). It is also possible to configure so that These shapes can be appropriately selected depending on the technique employed for etching and the conditions thereof.

  The emitter 105 has a structure in which a plurality of carbon nanotubes are entangled, and the carbon nanotube has a thin structure such as a single-walled carbon nanotube, a double-walled carbon nanotube, or a three-walled carbon nanotube.

  The emitter 105 is disposed on the facing region 108 of the cathode layer 102 exposed to the gap 107 and facing the slit 106. In its outline, thin carbon nanotubes support each other, and a part of the tip protrudes outward like a spine.

  Typically, a shape like a mountain range when the cathode layer 102 surface is considered as a plain, a shape where lawn grows in a tree shape or a belt shape when the cathode layer 102 surface is considered as a flat ground, or The brush hairs are shaped like strips on a flat surface. Hereinafter, these shapes and structures are referred to as “spinned structures”. In this figure, the rough shape of the spinous structure is a mountain range.

  In the figure, only one slit 106 is shown. However, when the field emission device 101 is used as an element for a field emission display, the same width (for example, 0.1 μm to 3 μm) is used. A plurality of slits 106 having the same length (for example, 10 μm to 500 μm) are arranged in parallel at equal intervals (for example, 1 μm to 1000 μm), and the carbon nanotubes having a spinous structure are formed from facing regions 108 facing each other. The emitter 105 is extended in the direction of the slit 106.

The thickness of the insulating layer 103 is typically 0.03 μm to 10 μm, and the carbon nanotubes constituting the emitter 105 are single to three layers, and thus the diameter is typically 0.4 nm to 0.3 nm. 10 nm. Further, the number density of the carbon nanotubes on the facing region is 10 ^{2 to} 10 ⁵ per 1 μm ² .

  In order to grow the carbon nanotubes constituting the emitter 105 at the number density as described above, a catalyst layer made of a transition metal such as molybdenum, cobalt, iron, or nickel is disposed between the emitter 105 and the cathode layer 102. 112 is arranged. As the catalyst used for the catalyst layer 112, a cobalt-molybdenum or iron-molybdenum binary system is considered to be particularly effective, but is not limited thereto, and a mixture containing the above transition metal can be used. .

  Further, a catalyst carrier layer 111 is disposed to suppress alloying of the catalyst layer 112 and the cathode layer 102 and to support the catalyst layer 112.

The catalyst carrier layer 111 is formed of a material containing one or more elements of Si, Al, Mg, O, N, and C. For example, AlO _x or aluminosilicate (a composite oxide of AlO _x and SiO _x ). And so on.

  In a conventional field emission device, a round hole is formed in the gate layer, and several carbon nanotubes are self-supported toward the hole to serve as an emitter. For this reason, the diameter of the carbon nanotube becomes thicker, the efficiency of electric field concentration becomes worse, and the driving voltage becomes higher. For this reason, a vicious circle has arisen in which the diameter of the carbon nanotube has to be further increased.

  In the present embodiment, the thin carbon nanotubes are entangled with each other and support each other to form a spine structure toward the slit 106, so that each tip of the emitter 105 can remain thin and extremely sharp. Therefore, the electric field can be efficiently concentrated, and for example, when used as an FED, the driving voltage can be reduced.

  The carbon nanotubes forming the emitter 105 are grown in a self-organized manner in a short time (typically about several seconds) by distributing the catalyst layer 112 at an appropriate density. Is easy.

  Further, in order to open a round hole in the gate layer in the conventional field emission device, an expensive pattern forming technique such as lithography has to be used. Further, mechanical pattern forming techniques such as stamping, scratching, and crack formation can be used, and the manufacturing cost can be reduced.

  Compared to the conventionally proposed method in which holes are formed in the gate layer and the emitters are arranged in a dot shape below the holes, in this embodiment, the slits 106 are formed in the gate layer 104 and the emitters 105 are arranged linearly thereunder. As a result, the mounting density of the emitters 105 can be greatly improved. As a result, the emission current can be greatly improved. It has been experimentally found that the mounting density of the emitters 105 can be improved by at least about two orders of magnitude.

  In the present embodiment, the reason why the emitters 105 can be arranged in a straight line is that the emitters 105 are composed of thin carbon nanotubes in which electric field concentration effectively occurs. Conventional thick carbon nanotubes are not suitable for linear arrangement because of insufficient electric field concentration.

  Hereinafter, an example of the manufacturing method of the field emission apparatus 101 according to the present embodiment will be described in detail. The numerical specifications shown below can be changed or adjusted as appropriate according to the application.

  3 (a) to (d), FIG. 4 (e) to (f), FIG. 5 (g) to (h), FIG. 6 (i) to (j), and FIG. 7 (k) to (l) FIG. 11 is a cross-sectional view showing a process for manufacturing the field emission device 101. Hereinafter, a description will be given with reference to FIG.

  First, a glass substrate or a silicon substrate with an oxide film is prepared as a substrate 121 on which the field emission device 101 is to be formed (FIG. 3A), and molybdenum is formed on the substrate 121 to a thickness of about 100 nm by sputtering. The cathode layer 102 is formed by film formation (FIG. 3B).

  Further, silicon oxide is formed to a thickness of 1 μm by a CVD method to form the insulating layer 103 (FIG. 3C).

  Next, molybdenum is deposited to a thickness of about 100 nm by sputtering to form the gate layer 104 (FIG. 3D).

  Further, a resist for pattern formation is applied to form a resist layer 301 (FIG. 4E), and a pattern 302 is formed on the resist layer 301 by electron beam lithography, photolithography, or the like (FIG. 4F). ). In general, the number of patterns 302 is increased in accordance with the plurality of slits 106. In this embodiment, the slit width of the pattern 302 is 0.1 μm to 0.5 μm, and the interval between the patterns 302 is 5 μm. However, this figure shows a state where there is one pattern 302.

  Then, the gate layer 104 is etched with a mixed solution of phosphoric acid, acetic acid, and nitric acid to form the slit 106 (FIG. 5G).

  The slit 106 can be formed by performing a process from application to etching of the resist layer 301 and employing a mechanical patterning method such as stamping or scratching as described above.

  Further, the insulating layer 103 is etched with a hydrofluoric acid aqueous solution to form the air gap 107 (FIG. 5H).

  Next, aluminum oxide is deposited to a thickness of 10 nm by sputtering to form the catalyst carrier layer 111 on the facing region 108 where the cathode layer 102 is exposed to the gap 107 (FIG. 6 (i)). . At this time, an aluminum oxide layer 303 having a similar thickness is also formed on the resist layer 301.

  Thereafter, the resist layer 301 and the aluminum oxide layer 303 on the resist layer 301 are stripped with a stripping solution (FIG. 6J).

  Then, cobalt is supplied through the slit 106 by sputtering, and a catalyst layer 112 is formed by forming a film with a thickness of 1 nm on the surface of the catalyst carrier layer 111 (FIG. 7 (k)).

  The catalyst carrier layer 111 serves to prevent the catalyst layer 112 and the cathode layer 102 from alloying and to further promote the growth of the carbon nanotubes on the catalyst layer 112.

  Although a catalyst layer is also formed on the gate layer 104, the catalyst layer is alloyed with the gate layer 104 because there is no catalyst carrier layer in between. Therefore, even if a catalyst layer is formed on the gate layer 104, the action can be eliminated.

  Note that the order of separation of the resist layer 301 and the aluminum oxide layer 303 and formation of the catalyst layer 112 may be interchanged.

  Thereafter, carbon nanotubes are grown from the catalyst layer 112 by a CVD process for supplying a carbon source such as alcohol to form the emitter 105 (FIG. 7L). As an example of conditions for driving the CVD apparatus, a mixture of hydrogen and argon can be supplied at a pressure of 20 tritelli (about 2670 Pa) and an air temperature of 800 ° C. for a maximum of 10 minutes at the time of catalytic reduction. A mixture of argon and argon can be supplied at a pressure of 30 torr (about 4000 Pa) and an air temperature of 800 ° C. for a maximum of 1 minute.

  In this way, the field emission device 101 is manufactured. In addition, said manufacturing conditions can be changed and various modifications are also included in the scope of the present invention.

  For example, the following aspects can be considered about the material of each member.

First, as the cathode layer 102 and the gate layer 104, a metal or alloy such as Mo, W, Ta, MoW, MoTa, Cr, n-type or p-type doped polycrystalline silicon, TaSi _x , MoSi _x , WSi _x , CrSi Metal silicides such as _x and metal nitrides such as TiN and TaN can be employed, and different materials may be employed in both layers.

  Next, the cathode layer 102 typically employs a single-layer structure of the above material. However, when resistance becomes a problem due to an increase in the size of the panel, the field emission device 101 is manufactured by a low-temperature process. It is also possible. In this case, the cathode layer 102 may have a laminated structure of the common material and Al or Cu, or a clad structure of the common material and Al or Cu. Here, the “cladding structure” is a structure in which the surface of Al or Cu is covered with the above-described material to impart chemical resistance or the like.

Further, as the gate layer 104, a part of polycrystalline silicon may be silicided. This is because, when Co, Ni, Mo, Fe, or the like is spread to form the catalyst layer 112, part of the silicon of the gate becomes CoSi _x , NiSi _x , MoSi _x , FeSi _x , and the resistance decreases.

  When the gate layer 104 is made of polysilicon, self-alignment occurs when the catalyst layer 112 is formed, so that the gate layer 104 necessarily has a laminated structure with silicide. In this case, there is an advantage that the resistance can be reduced. However, depending on the panel size, the gate layer 104 is not formed as a single layer as a whole, but is configured by combining members and wiring. Also good.

In addition, as the insulating layer 103, not only SiO _x as described above, but also one or more elements of Si, C, O, and N, such as SiO _x N _y , SiN _x , or a laminated structure thereof, are used. It is also possible to employ an insulator that contains the same.

(Experimental example)
Below, the result of having confirmed the performance of the field emission apparatus 101 manufactured on various manufacturing conditions by experiment is demonstrated. The experiment was performed by manufacturing five types of field emission devices 101 of A to E.

  In the gate layer 104 of the field emission device 101, slits 106 having a width of 0.5 μm, a distance of 5 μm, and a length of about 0.5 mm were arranged in a 2 mm × 2 mm section.

  The insulating layer 103 made of silicon oxide was 1 μm, the gate layer 104 made of molybdenum was 120 nm, the catalyst carrier layer 111 made of aluminum oxide was 10 nm, and the catalyst layer 112 was made of cobalt.

  Each of the five types of A to E is as follows.

  (Sample A) The cathode layer 102 is a silicon substrate, the thickness of the catalyst layer 112 is 1 nm, the CVD time is 15 seconds, and the CVD temperature is 700 ° C.

  (Sample B) The cathode layer 102 is a silicon substrate, the thickness of the catalyst layer 112 is 1 nm, the CVD time is 5 seconds, and the CVD temperature is 800 ° C.

  (Sample C) The cathode layer 102 is a silicon substrate, the thickness of the catalyst layer 112 is 1.2 nm, the CVD time is 5 seconds, and the CVD temperature is 800 ° C.

  (Sample D) The cathode layer 102 is a silicon substrate, the thickness of the catalyst layer 112 is 1 nm, the CVD time is 15 seconds, and the CVD temperature is 800 ° C.

  (Sample E) The cathode layer 102 is formed by forming molybdenum with a thickness of 140 nm on a silicon substrate with an oxide film, the thickness of the catalyst layer 112 is 1 nm, the CVD time is 5 seconds, and the CVD temperature is 800 ° C.

  8, 9, 10, and 11 are explanatory views showing electron micrographs of the field emission device 101 manufactured with the above specifications. Hereinafter, a description will be given with reference to FIG. 8 shows Sample A, FIG. 9 shows Sample B, FIG. 10 shows Sample C, and FIG. 11 shows Sample D.

  As can be seen from these photographs, the carbon nanotubes are intertwined to form a spine-like structure, and the outer shape is a brush-like, mountain-like, lawn-like, or tree-like shape.

  Further, as is apparent from FIGS. 10 and 11, it can be seen that the shape of the gap 107 is a semi-cylindrical shape having the slit 106 as a central axis or a bowl shape.

  FIG. 12 is a graph showing the relationship between the gate voltage and the emitter (anode) current density in Samples A to D. Hereinafter, a description will be given with reference to FIG. In this figure, the horizontal axis indicates the gate voltage (Gate Voltage) applied between the cathode layer 102 and the gate layer 104, and the vertical axis indicates the anode current density (Anode Current Density) that flows when electrons are emitted from the emitter 105. Are shown respectively.

  From this figure, it can be seen that Sample A and Sample B have higher performance as a field emission device than Sample C and Sample C.

In Sample B, it can be seen that a favorable value of 1 mA / cm ^{2 of} anode current density was obtained for a gate voltage of 70V.

  FIG. 13 is an explanatory diagram showing a state in which Samples A to C are emitted using a field emission display. Hereinafter, a description will be given with reference to FIG.

  As shown in the figure, when Sample A is applied with 25V and Sample B is applied with 20V, light emission is started uniformly, and in Sample B, a good light emission phenomenon can be seen. Recognize.

  FIG. 14 is a graph showing the relationship between the gate voltage and the emission (anode) current density in Sample B and Sample E. Hereinafter, a description will be given with reference to FIG. In this figure, the horizontal axis indicates the gate voltage (Gate Voltage) applied between the cathode layer 102 and the gate layer 104, and the vertical axis indicates the anode current density (Anode Current Density) that flows when electrons are emitted from the emitter 105. Shows the relationship.

In this experiment, the distance between the gate layer 104 and the anode electrode is 150 μm, the gate voltage is changed between 0 V and 70 V, the anode voltage (voltage between the cathode layer 102 and the anode electrode) is 300 V, and vacuum The degree was set to 1 × 10 ⁻⁵ Pa.

  Comparing the example shown in this figure with Sample B, it can be seen that the emission start voltage is reduced to 15 V and the anode current density is improved when viewed at the same gate voltage.

  As described above, it has been experimentally shown that the field emission device 101 according to the present embodiment has good performance.

  According to the present invention, it is possible to provide a field emission apparatus and a method for manufacturing the field emission apparatus that are suitable for efficiently concentrating an electric field to emit electrons and realizing a high emission current density with a low driving voltage. .

It is a perspective view which shows the mode of the field emission apparatus which concerns on one of embodiment of this invention. It is sectional drawing of the said field emission apparatus. (A)-(d) is sectional drawing which shows the process in which a field emission apparatus is manufactured. (E)-(f) is sectional drawing which shows the process in which a field emission apparatus is manufactured. (G)-(h) is sectional drawing which shows the process in which a field emission apparatus is manufactured. (I)-(j) is sectional drawing which shows the process in which a field emission apparatus is manufactured. (K)-(l) is sectional drawing which shows the process in which a field emission apparatus is manufactured. It is explanatory drawing which shows the electron micrograph of Sample A of a field emission apparatus. It is explanatory drawing which shows the electron micrograph of Sample B of a field emission apparatus. It is explanatory drawing which shows the electron micrograph of Sample C of a field emission apparatus. It is explanatory drawing which shows the electron micrograph of Sample D of a field emission apparatus. It is a graph which shows the relationship between the gate voltage in Sample A of a field emission apparatus, and an emitter (anode) current density. It is explanatory drawing which shows a mode that it emitted light using Sample A thru | or C of a field emission apparatus as a field emission display. It is a graph which shows the relationship between the gate voltage in Sample B of a field emission apparatus, and Sample E, and an emission (anode) current density.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Field emission apparatus 102 Cathode layer 103 Insulating layer 104 Gate layer 105 Emitter 106 Slit 107 Space | gap 108 Opposite area 111 Catalyst support layer 112 Catalyst layer 121 Substrate 301 Resist layer 302 Pattern 303 Aluminum oxide layer

Claims (15)

A cathode layer made of a conductor;
An insulating layer disposed on the cathode layer;
A gate layer made of a conductor provided on the insulating layer and provided with a slit;
With
The insulating layer is provided with a gap from the slit to a facing region facing the slit in the cathode layer,
An emitter composed of a structure in which a plurality of carbon nanotubes arranged on the facing region are intertwined;
A field emission device further comprising: The field emission device according to claim 1,
Some or all of the plurality of carbon nanotubes extend from the facing region toward the slit,
A field emission device characterized in that the general shape of the structure is a mountain range, a brush shape, a tree line shape, or a lawn belt shape. The field emission device according to claim 1 or 2,
The carbon nanotube is a single-walled carbon nanotube, a double-walled carbon nanotube, or a triple-walled carbon nanotube. The field emission device according to claim 3,
The slit has a width of 0.1 μm to 3 μm,
The length of the slit is 10 μm to 500 μm,
The insulating layer has a thickness of 0.03 μm to 10 μm,
The carbon nanotube has a diameter of 0.4 nm to 10 nm,
A number density of the carbon nanotubes on the facing region is 10 ^{2 to} 10 ⁵ per 1 μm ² . The field emission device according to claim 4,
A plurality of the slits are provided in parallel,
The field emission device characterized in that the interval between the plurality of slits is 1 μm to 1000 μm. The field emission device according to any one of claims 3 to 5,
A catalyst layer for promoting the growth of the carbon nanotubes between the emitter and the cathode layer;
In order to suppress alloying with the said catalyst layer and the said cathode layer, the catalyst carrier layer which carry | supports the said catalyst layer is further provided, The field emission apparatus characterized by the above-mentioned. The field emission device according to claim 6,
The cathode layer includes Mo, W, Ta, MoW, MoTa, Cr, other metals or alloys, TaSi _x , MoSi _x , WSi _x , CrSi _x , other metal silicides, TiN, TaN, other metal nitrides, It is formed by a single layer structure of n-type or p-type doped polycrystalline silicon, or a laminated structure of these and Al or Cu, or a cladding structure of Al or Cu,
The gate layer is made of Mo, W, Ta, MoW, MoTa, Cr, other metals or alloys, TaSi _x , MoSi _x , WSi _x , CrSi _x , other metal silicides, TiN, TaN, other metal nitrides A single layer structure is formed by a laminated structure in which a part of n-type or p-type doped polycrystalline silicon is silicided,
The catalyst carrier layer is formed of a substance containing one or more elements of Si, Al, Mg, O, N, and C;
The catalyst layer is formed of cobalt, iron, nickel, molybdenum, or a mixture containing these,
The insulating layer is formed of a single-layer structure of SiO _x , SiO _x N _y , or SiN _x or a stacked structure thereof. A cathode layer forming step of forming a cathode layer made of a conductor on the substrate;
An insulating layer forming step of forming an insulating layer made of an insulator on the formed cathode layer;
A gate layer forming step of forming a gate layer made of a conductor on the formed insulating layer;
A slitting step for providing a slit in the deposited gate layer;
A gap step of removing the insulating layer and providing a gap so that a facing region of the cathode layer facing the slit is exposed through the provided slit,
A method of manufacturing a field emission device, comprising: forming an emitter having a structure in which a plurality of carbon nanotubes are entangled with each other on the facing region. It is a manufacturing method of the field emission device according to claim 8,
In the emitter forming step, some or all of the plurality of carbon nanotubes are extended from the facing region toward the slit, and the rough shape of the structure is a mountain range, a brush shape, a tree line shape, or a lawn. A method of manufacturing a field emission device, characterized in that it is in the form of a strip. It is a manufacturing method of the field emission device according to claim 9,
The carbon nanotube is formed by a chemical vapor deposition method for supplying carbon,
A method for manufacturing a field emission device, characterized in that the supply concentration and supply time of the carbon source are set so that the carbon nanotubes are single-walled carbon nanotubes, double-walled carbon nanotubes, or triple-walled carbon nanotubes. It is a manufacturing method of the field emission device according to claim 9 or 10,
The slit has a width of 0.1 μm to 3 μm,
The length of the slit is 10 μm to 500 μm,
The insulating layer has a thickness of 0.03 μm to 10 μm,
The carbon nanotube has a diameter of 0.4 nm to 10 nm,
The number density of the carbon nanotubes on the facing region is 10 ^{2 to} 10 ⁵ per 1 μm ² . It is a manufacturing method of the field emission device according to claim 11,
A plurality of the slits are provided in parallel,
The method of manufacturing a field emission device, wherein the interval between the plurality of slits is 1 μm to 1000 μm. It is a manufacturing method of the field emission device according to claim 11 or 12,
The slit is formed by forming a resist layer on the gate layer, forming a slit in the resist layer by lithography, stamping, scratching, or crack formation, and etching the gate layer through the slit. A method of manufacturing a field emission device, comprising: forming a field emission device. It is a manufacturing method of the field emission device according to any one of claims 10 to 13,
A catalyst carrier layer step of forming a catalyst carrier layer on the opposing region through the slit after the opposing region is exposed;
A catalyst layer step of forming a catalyst layer for promoting the growth of the carbon nanotubes on the catalyst support layer through the slit and supporting the catalyst layer on the catalyst support layer;
A method of manufacturing a field emission device, comprising causing a catalyst carrier layer to suppress alloying of the catalyst layer and the cathode layer. A method of manufacturing a field emission device according to claim 14,
The cathode layer and the gate layer are formed by a sputtering method for supplying molybdenum,
The catalyst carrier layer is formed by a sputtering method for supplying aluminum oxide,
The catalyst layer is formed by a sputtering method for supplying cobalt,
The insulating layer is formed by a chemical vapor deposition method in which silicon oxide is supplied. A method for manufacturing a field emission device.

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