TWI451466B - Field emission device and fabricating method thereof - Google Patents

Description

Field emission structure and manufacturing method thereof

The present application relates to a field emission structure and a method of fabricating the same, and more particularly to a field emission structure that effectively reduces the screen effect and a method of fabricating the same.

With the advancement of technology, the huge cathode ray tube (CRT) display has gradually entered history. Therefore, field display devices such as Field Emission Display (FED), Liquid Crystal Display (LCD), and Plasma Display Panel (PDP) are gradually becoming the mainstream of future displays. Taking the field emission display as an example, since the field emission display has a short optical response time, almost no image sticking occurs. That is, the field emission display has higher display quality than the liquid crystal display and the plasma flat display. In addition, field emission displays have the advantages of thin thickness, light weight, wide viewing angle, high brightness, large operating temperature range and energy saving. Therefore, field emission displays have gradually attracted the attention of the global industry.

Common field emission sources include zero-dimensional nano-dot, one-dimensional nanowire or carbon nanotube, two-dimensional nano-flake, three-dimensional nano-tip (nano-tip). In addition to the material work function of the field emission source, the field enhancement factor is another important factor in determining the field emission characteristics of the field emission source. Generally, one-dimensional nanowires or carbon nanotubes have better field emission enhancement. Because the nanowire or carbon nanotube has a small radius of curvature and a large aspect ratio.

Appropriate control of the density of the nanowire or carbon nanotube can effectively suppress the shielding effect. At present, the prior art controls the thickness of the catalyst layer, controls the concentration ratio of the carbon source, the hydrogen gas, the ammonia gas, or transmits Selective growth is the way to control the density of carbon nanotubes. However, the above methods still do not control the density of the growing carbon nanotubes very effectively. In addition, the selective growth described above can only grow carbon nanotubes in a small area, and it is impossible to grow carbon nanotubes over a large area.

In view of the above, how to grow carbon nanotubes on a large area and effectively control the density of carbon nanotubes is one of the problems faced by the field emission field.

The present application provides a field emission structure and a method of fabricating the same to effectively control the growth density of the carbon nanotubes, thereby reducing the shielding effect.

The application provides a field emission structure including a substrate, a nanometer taper, a catalyst layer, and a plurality of carbon nanotubes. The nano-cone includes a bottom portion disposed on the substrate and a tip portion positioned above the bottom portion. The catalyst layer covers the nano-cone and the carbon nanotube is located on the surface of the tip portion.

In an embodiment of the invention, the nanometer tip cone is a pyramidal cone tip or a conical nanotip.

In an embodiment of the invention, the bottom of the aforementioned tip taper is divided into a cylinder or a polygonal cylinder, and the tip end portion is a cone or a pyramid.

In an embodiment of the invention, the carbon nanotubes are passed through the catalyst layer and exposed to the outside of the catalyst layer.

In an embodiment of the invention, the material of the bottom portion comprises a semiconductor material, and the material of the tip portion comprises metal or titanium nitride (TiNx).

In an embodiment of the invention, the aforementioned semiconductor material is, for example, germanium, and the aforementioned metal is, for example, titanium (Ti) or tantalum (Ta).

In an embodiment of the invention, the material of the catalyst layer is, for example, iron, cobalt or nickel.

In an embodiment of the invention, the field emission structure may further include a patterned dielectric layer and a gate, wherein the patterned dielectric layer is disposed on the substrate, and the dielectric layer has an opening to accommodate the nanotip The cone is disposed on the patterned dielectric layer.

In an embodiment of the invention, the substrate comprises an insulating substrate, an electrode layer, a resistive layer and a semiconductor layer, wherein the electrode layer is disposed on the insulating substrate, the resistive layer is disposed on the electrode layer, and the semiconductor The layer is disposed on the impedance layer, and the nanometer tip cone is disposed on the impedance layer.

In an embodiment of the invention, the aforementioned tip taper may further include a middle portion between the tip end portion and the bottom portion. For example, the material of the bottom portion is, for example, a semiconductor material, the material of the middle portion is, for example, a metal or titanium nitride, and the material of the tip portion includes an oxide of the foregoing metal or an oxide of titanium nitride.

The present application provides a method for fabricating a field emission structure, comprising the steps of: sequentially forming a first material layer and a second material layer on a substrate; performing an oxidation process to oxidize the second material layer into a porous material a layer and oxidize a portion of the first material layer exposed by the porous material layer a nano-point; removing the porous material layer to expose the first material layer and the nano-dots; using a nano-dots as a mask to remove a portion of the first material layer and a portion of the substrate to form a plurality of nanoparticles on the substrate a tapered cone; forming a catalyst layer on each nanometer tip cone, and the thickness of the catalyst layer is, for example, between 2 nm and 70 nm; and forming a plurality of carbons on each of the nanometer tapers Nano tube.

In an embodiment of the invention, the material of the first material layer is, for example, titanium, tantalum or titanium nitride, and the material of the nano point is, for example, titanium oxide or tantalum oxide.

In an embodiment of the invention, the material of the second material layer is, for example, aluminum.

In an embodiment of the invention, after the second material layer is oxidized, the porous material layer has a plurality of pin holes corresponding to the nano-dots.

In an embodiment of the invention, each of the nanometer tapers includes a bottom portion disposed on the substrate, a tip portion disposed above the bottom portion, and an intermediate portion between the tip portion and the bottom portion, respectively. After removing a portion of the first material layer and a portion of the substrate to form a nano-tip, the nano-dots respectively form a tip portion, and the unremoved first material layer constitutes the intermediate portion, and the unremoved portion of the substrate constitutes the bottom portion section.

In an embodiment of the invention, each of the nanometer tapers includes a bottom portion disposed on the substrate and a tip portion disposed above the bottom portion, and the first material layer and the portion of the substrate are removed to form a portion. After the nano-cone, the nano-dots are completely removed, the first layer of material that has not been removed constitutes the tip portion, and the portion of the substrate that has not been removed constitutes the bottom portion.

In an embodiment of the invention, the manufacturer of the aforementioned field emission structure is The method may further include the steps of: sequentially forming a dielectric material layer and a conductive material layer on the substrate before forming the carbon nanotube; and removing a portion of the conductive material layer and the portion of the dielectric material layer on the substrate A gate and a patterned dielectric layer are formed, wherein the patterned dielectric layer has an opening to accommodate the nano-tip, and the gate is disposed on the patterned dielectric layer.

In an embodiment of the invention, the substrate is, for example, a semiconductor substrate.

In an embodiment of the invention, the substrate comprises an insulating substrate, an electrode layer, a resistive layer and a semiconductor layer, wherein the electrode layer is disposed on the insulating substrate, the resistive layer is disposed on the electrode layer, and the semiconductor layer Disposed on the impedance layer, the aforementioned first material layer is formed on the semiconductor layer, and the semiconductor layer is partially removed, and a portion of the semiconductor layer not removed constitutes a bottom portion.

The above and other objects, features, and advantages of the present invention will become more apparent and understood.

[First Embodiment]

1A to 1F are views showing a method of fabricating a field emission structure according to a first embodiment of the present invention. Referring to FIG. 1A , first, a first material layer 110 and a second material layer 120 are sequentially formed on a substrate 100 . In the present embodiment, the substrate 100 is, for example, a semiconductor substrate, and the material thereof is, for example, germanium or other semiconductor material. For example, the material of the substrate 100 may be low resistive silicon. In addition, a first material layer formed on the substrate 100 110 is, for example, a titanium layer, a tantalum layer or titanium nitride (TiNx), and the second material layer 120 formed on the first material layer 110 is, for example, an aluminum layer. It should be noted that the material of the second material layer 120 may be any material having porous properties after being oxidized.

Referring to FIG. 1B, an oxidation process is performed to oxidize the second material layer 120 into a porous material layer 130. In this embodiment, the foregoing oxidation process is, for example, an anodization process.

During the foregoing oxidation process, a plurality of pin holes 130a are formed in the porous material layer 130, and these pinholes 130a are randomly and uniformly distributed in the porous material layer 130. The pinhole 130a distributed in the porous material layer 130 exposes a portion of the surface of the first material layer 110, and causes the first material layer 110 exposed by the pinhole 130a to be oxidized into a plurality of nano-dots 112. That is, during the aforementioned oxidation process, the formation of the nano-dots 112 may be later than the formation of the pinholes 130a in the porous material layer 130. It should be noted that the size, number, and formation position of the nano-dots 112 depend on the size, number, and location of the pinholes 130a in the porous material layer 130, and the field has a formula that can be adjusted by the usual knowledge of the oxidation process. The size, number, and location of the pinholes 130a are controlled to control the size, number, and location of the nano-dots 112.

In this embodiment, the material of the nano-dots 112 is related to the first material layer 110. When the first material layer 110 is a titanium layer or a titanium nitride layer, the formed nano-dots 112 are made of titanium oxide. When the first material layer 110 is a tantalum layer, the material of the formed nano-dots 112 is tantalum oxide.

Referring to FIG. 1C, the porous material layer 130 is removed to expose the first material layer 110 and the nano-dots 112. In this embodiment, the porosity is removed The method of material layer 130 is, for example, wet etching

Referring to FIG. 1D, with the nano-dots 112 as a mask, a portion of the first material layer 110 not covered by the nano-dots 112 and a portion of the substrate 100 are removed to form a plurality of intermediate portions 110a and a plurality of bottom portions 100a. In detail, after removing a portion of the first material layer 110 and a portion of the substrate 100, the first material layer 110 that has not been removed may constitute the intermediate portion 110a, and the portion of the substrate 100 that has not been removed constitutes the bottom portion 100a. In the present embodiment, the method of removing the first material layer 110 and the substrate 100 is, for example, dry etching.

During the removal of a portion of the first material layer 110 and a portion of the substrate 100, the nano-dots 112 are also partially removed to form the tip portion 112a. The tip end portion 112a, the intermediate portion 110a, and the bottom portion 100a constitute the nano-tip T, and the nano-tip T is located on a thin substrate 100b.

In this embodiment, the nano-tip cone T is, for example, a pyramidal-shaped nano-cone or a conical nano-cone, and the bottom portion 100a of the nano-cone T is, for example, a cylinder or a polygonal cylinder, and the tip is The portion 112a is, for example, a cone or a pyramid. In addition, the material of the bottom portion 100a is the same as the substrate 100b (for example, germanium), and the material of the intermediate portion 110a and the first material layer 110 is the same as the metal (for example, titanium or tantalum) or the same as the titanium nitride, and the tip portion 112a. The material of the nano-dots 112 is the oxide of the aforementioned metal (for example, titanium oxide or cerium oxide) or the oxide of titanium nitride (TiNx) (that is, titanium oxide).

It should be noted that in other embodiments (as shown in FIG. 1D'), during the removal of portions of the first material layer 110 and portions of the substrate 100, the nano-dots 112 may also be completely removed. At this time, the first material layer 110 which has not been removed constitutes the so-called tip portion 110a' without being removed. A portion of the substrate constitutes a so-called bottom portion 100a, which is shown in Fig. 1D'. The aforementioned tip portion 110a' and the bottom portion 100a' constitute a nano-tip T", and the nano-tip T" will be located on a thin substrate 100b. In detail, the material of the tip end portion 110a' of the nano-tip T" is, for example, a metal such as titanium or tantalum or titanium nitride.

Referring to FIG. 1E, a catalyst layer 140 is formed on each of the nano-tips T. In this embodiment, the material of the catalyst layer 140 used is, for example, iron, cobalt or nickel, wherein the thickness of the catalyst layer 140 is, for example, between 2 nm and 70 nm.

Since the material of the bottom portion 100a' is a semiconductor material, the bottom portion 100a' reacts with the catalyst layer 140 to form a compound. For example, when the material of the bottom portion 100a' is 矽 and the catalyst layer 140 is a metal such as iron, cobalt or nickel, the bottom portion 100a' reacts with the catalyst layer 140 to form a metal silicide. Further, since the material of the tip end portion 112a is, for example, titanium oxide or yttrium oxide, the tip end portion 112a does not easily react with the catalyst layer 140 to form a compound.

Referring to FIG. 1F, a plurality of carbon nanotubes 150 are formed on the tip end portions 112a of the respective tip cones T. Since the bottom portion 100a reacts with the catalyst layer 140 to form a compound (for example, a metal halide), and the tip portion 112a does not easily react with the catalyst layer 140 to form a compound, the surface of the tip portion 112a is more likely to grow carbon. The nanotube tube 150 is more likely to grow out of the carbon nanotube tube 150 on the surface of the bottom portion 100a. In other words, if the carbon nanotube 150 is to be grown on the surface of the tip portion 112a, the required growth temperature is low (about 200 degrees Celsius to 1000 degrees Celsius); if carbon nanotubes are to be grown on the surface of the bottom portion 100a Tube 150, the required growth temperature is higher (about 450 degrees Celsius to 1000 degrees Celsius). As can be seen from the above, in this embodiment, the carbon nanotubes 150 can be selectively grown on the surface of the tip end portion 112a only by appropriate temperature control.

Similarly, when the tip portion 110a' is metal or titanium nitride (as shown in FIG. 1D'), the tip portion 110a' does not easily react with the subsequently formed catalyst layer 140 to form a compound, so the tip of FIG. 1D' The portion 110a' has the same function as the tip end portion 112a of FIG. 1D, contributing to the selective growth of the carbon nanotube 150.

As shown in FIG. 1F, the carbon nanotube 150 of the present embodiment penetrates the catalyst layer 140 and is partially exposed outside the catalyst layer 140.

[Second embodiment]

2A to 2H are views showing a method of fabricating a field emission structure according to a second embodiment of the present invention. The process illustrated in FIG. 2A to FIG. 2E of the present embodiment is the same as that of FIG. 1A to FIG. 1E of the first embodiment, and thus will not be repeated herein.

Referring to FIG. 2F, after forming the catalyst layer 140, a dielectric material layer 160 and a conductive material layer 170 are sequentially formed on the substrate 100b. As can be seen from FIG. 2F, the dielectric material layer 160 and the conductive material layer 170 are entirely covered on the substrate 100b, the nano-tip T and the catalyst layer 140.

Referring to FIG. 2G, a portion of the conductive material layer 170 and a portion of the dielectric material layer 160 are removed to form a gate 170a and a patterned dielectric layer 160a on the substrate 100b, wherein the patterned dielectric layer 160a has an opening 162. The nano-tip T is accommodated, and the gate 170a is disposed on the patterned dielectric layer 160a.

Please refer to FIG. 2H on the tip end portion 112a of each nano-tip T A plurality of carbon nanotubes 150 are formed separately. Since the bottom portion 100a reacts with the catalyst layer 140 to form a compound (for example, a metal halide), and the tip portion 112a does not easily react with the catalyst layer 140 to form a compound, the surface of the tip portion 112a is more likely to grow carbon. The nanotube tube 150 is more likely to grow out of the carbon nanotube tube 150 on the surface of the bottom portion 100a. In other words, if the carbon nanotube 150 is to be grown on the surface of the tip portion 112a, the required growth temperature is low (about 200 degrees Celsius to 1000 degrees Celsius); if carbon is to be grown on the surface of the bottom portion 100a The nanotubes 150 have a higher growth temperature (about 450 degrees Celsius to 1000 degrees Celsius). As can be seen from the above, in this embodiment, the carbon nanotubes 150 can be selectively grown on the surface of the tip end portion 112a only by appropriate temperature control.

As shown in FIG. 2H, the carbon nanotube 150 of the present embodiment penetrates the catalyst layer 140 and is partially exposed outside the catalyst layer 140.

[Third embodiment]

3A to 3F are views showing a method of fabricating a field emission structure according to a third embodiment of the present invention. Referring to FIG. 3A to FIG. 3F, the present embodiment is similar to the first embodiment, but the main difference between the two is that the substrate 100' used in the embodiment is different from the substrate 100 used in the first embodiment, so Only the differences between the two embodiments will be described.

The substrate 100' used in this embodiment includes an insulating substrate S, an electrode layer E, a resistive layer R, and a semiconductor layer SE. The electrode layer E is disposed on the insulating substrate S, and the resistive layer R is disposed on the electrode layer. In E, the semiconductor layer SE is disposed on the resistive layer R, and the first material layer 110 is formed on the semiconductor layer SE. The foregoing semiconductor layer SE material may be 矽 or other half Conductor material. For example, the material of the substrate 100 can be a low resistance 矽.

As shown in FIG. 3D, after the first material layer 110 not covered by the nano-dots 112 and the portion of the substrate 100 (ie, the semiconductor layer SE) are removed by the nano-dots 112 as a mask, the first is not removed. The material layer 110 will constitute the intermediate portion 110a, and the unremoved semiconductor layer will constitute the bottom portion SE'. During the removal of a portion of the first material layer 110 and a portion of the substrate 100, the nano-dots 112 are also partially removed to form the tip portion 112a. The tip end portion 112a, the intermediate portion 110a, and the bottom portion SE' constitute the nano-tip T', and the nano-tip T' will be located on the resistive layer R of the substrate 100'.

It is noted that in other embodiments (as shown in Figure 3D'), the nano-dots 112 may also be completely removed during the removal of portions of the first material layer 110 and portions of the substrate 100. At this time, the first material layer 110 which has not been removed constitutes a so-called tip portion 110a', and the semiconductor layer SE which has not been removed constitutes a so-called bottom portion SE', which is shown in Fig. 3D'. The aforementioned tip end portion 110a' and the bottom portion SE' constitute the nano-tip cone T'''. In detail, the material of the tip end portion 110a' of the tip taper T''' is, for example, metal or titanium nitride.

Similarly, when the tip portion 110a' is metal or titanium nitride (as shown in FIG. 3D'), the tip portion 110a' does not easily react with the subsequently formed catalyst layer 140 to form a compound, so the tip of FIG. 3D' Portion 110a' has the same function as tip end portion 112a of Figure 3D, facilitating selective growth of carbon nanotube 150.

Fourth Embodiment

4A to 4H are diagrams showing a field emission structure of a fourth embodiment of the present invention; Production method. Referring to FIG. 4A to FIG. 4H, this embodiment is similar to the second embodiment, but the main difference between the two is that the substrate 100' used in the embodiment is different from the substrate 100 used in the second embodiment, so Only the differences between the two embodiments will be described.

The substrate 100' used in this embodiment includes an insulating substrate S, an electrode layer E, a resistive layer R, and a semiconductor layer SE. The electrode layer E is disposed on the insulating substrate S, and the resistive layer R is disposed on the electrode layer. In E, the semiconductor layer SE is disposed on the resistive layer R, and the first material layer 110 is formed on the semiconductor layer SE. The foregoing semiconductor layer SE material may be germanium or other semiconductor material. For example, the material of the substrate 100 can be a low resistance 矽.

As shown in FIG. 4D, after the first material layer 110 not covered by the nano-dots 112 and a portion of the substrate 100 (ie, the semiconductor layer SE) are removed with the nano-dots 112 as a mask, the first is not removed. The material layer 110 will constitute the intermediate portion 110a, and the unremoved semiconductor layer will constitute the bottom portion SE'. During the removal of a portion of the first material layer 110 and a portion of the substrate 100, the nano-dots 112 are also partially removed to form the tip portion 112a. The tip end portion 112a, the intermediate portion 110a, and the bottom portion SE' constitute the nano-tip T', and the nano-tip T' will be located on the resistive layer R of the substrate 100'.

In the above embodiment of the present application, the use of a nano-dots as a mask to form a nano-tip can effectively control the growth density of the carbon nanotubes, thereby reducing the shielding effect.

Although the present application has been disclosed in the above preferred embodiments, it is not intended to limit the application, and anyone skilled in the art will not depart from the present application. In the spirit and scope, the scope of protection of this application is subject to the definition of the scope of the patent application.

100, 100b, 100'‧‧‧ substrates

100a, SE’‧‧‧ bottom part

110‧‧‧First material layer

110a‧‧‧ middle part

112‧‧‧Nee Point

112a, 110a’‧‧‧ tip part

120‧‧‧Second material layer

130‧‧‧Porosive material layer

130a‧‧ pinhole

T, T', T", T'''‧‧‧ nm rice cone

140‧‧‧ catalyst layer

150‧‧‧Carbon nanotubes

160‧‧‧ dielectric material layer

160a‧‧‧ patterned dielectric layer

162‧‧‧ openings

170‧‧‧ Conductive material layer

170a‧‧‧ gate

S‧‧‧Insulation substrate

E‧‧‧electrode layer

R‧‧‧ impedance layer

SE‧‧‧Semiconductor layer

1A to 1F are views showing a method of fabricating a field emission structure according to a first embodiment of the present invention.

Figure 1D' is a schematic cross-sectional view of another nano-tip.

2A to 2H are views showing a method of fabricating a field emission structure according to a second embodiment of the present invention.

3A to 3F are views showing a method of fabricating a field emission structure according to a third embodiment of the present invention.

Figure 3D' is a schematic cross-sectional view of another nano-tip.

4A through 4H illustrate a method of fabricating a field emission structure in accordance with a fourth embodiment of the present invention.

100‧‧‧Substrate

110‧‧‧First material layer

112‧‧‧Nee Point

130‧‧‧Porosive material layer

130a‧‧ pinhole

Claims (21)

A field emission structure includes: a substrate; a nano-tip, comprising a bottom portion disposed on the substrate and a tip portion above the bottom portion, wherein the bottom portion is made of a semiconductor material, and the material The material of the tip portion includes metal or titanium nitride; a catalyst layer covering the nano-tip; and a plurality of carbon nanotubes on the surface of the tip portion. The field emission structure of claim 1, wherein the nano-cone is a pyramidal cone or a conical nano-cone. The field emission structure of claim 1, wherein the bottom of the nano-cone is divided into a cylinder or a polygonal cylinder, and the tip portion is a cone or a pyramid. The field emission structure of claim 1, wherein the carbon nanotubes extend through the catalyst layer and are exposed outside the catalyst layer. The field emission structure of claim 1, wherein the semiconductor material comprises germanium and the metal comprises titanium (Ti) or tantalum (Ta). The field emission structure of claim 1, wherein the material of the catalyst layer comprises iron, cobalt or nickel, and the thickness of the catalyst layer is between about 2 nm and 70 nm. The field emission structure of claim 1, further comprising: a patterned dielectric layer disposed on the substrate, the patterned dielectric layer having an opening to accommodate the nano-spike; and a gate The pole is disposed on the patterned dielectric layer. The field emission structure of claim 1, wherein the field emission structure The substrate includes: an insulating substrate; an electrode layer disposed on the insulating substrate; a resistive layer disposed on the electrode layer; and a semiconductor layer disposed on the resistive layer, wherein the nano-cone is It is disposed on the impedance layer. The field emission structure of claim 1, wherein the nano-cone further comprises an intermediate portion between the tip portion and the bottom portion. The field emission structure of claim 9, wherein the material of the bottom portion comprises a semiconductor material, the material of the intermediate portion comprises a metal or titanium nitride, and the material of the tip portion comprises the oxide of the metal . The field emission structure of claim 10, wherein the semiconductor material comprises germanium, the metal comprises titanium (Ti) or tantalum (Ta), and the oxide of the metal comprises titanium oxide (TiOx) or tantalum oxide ( TaOx). A method for fabricating a field emission structure includes: sequentially forming a first material layer and a second material layer on a substrate; performing an oxidation process to oxidize the second material layer into a porous material layer and The exposed portion of the first material layer of the porous material layer is oxidized into a plurality of nano-dots; the porous material layer is removed to expose the first material layer and the nano-dots; and the nano-dots are used as a mask a screen, removing a portion of the first material layer and a portion of the substrate to form a plurality of nano-tips; Forming a catalyst layer on each of the nanometer cones; and forming a plurality of carbon nanotubes on each of the nanometer cones. The method for manufacturing a field emission structure according to claim 12, wherein the material of the first material layer comprises titanium, tantalum or titanium nitride, and the material of the nano point comprises titanium oxide or tantalum oxide. The method of fabricating a field emission structure according to claim 12, wherein the material of the second material layer comprises aluminum. The method of fabricating a field emission structure according to claim 12, wherein the porous material layer has a plurality of pinholes corresponding to the nano-dots after the second material layer is oxidized. The method for manufacturing a field emission structure according to claim 12, wherein each of the nanometer cones comprises a bottom portion disposed on the substrate, a tip portion located above the bottom portion, and a tip portion An intermediate portion between the portion and the bottom portion, and after removing the portion of the first material layer and a portion of the substrate to form the plurality of nano-tips, the nano-dots respectively constitute the tip portions, and are not moved The first layer of material is formed to form the intermediate portions, and the portion of the substrate that is not removed constitutes the bottom portions. The method for manufacturing a field emission structure according to claim 12, wherein each of the nanometer cones comprises a bottom portion disposed on the substrate and a tip portion disposed above the bottom portion, and is removed After a portion of the first material layer and a portion of the substrate to form the nano-tips, the nano-dots are completely removed, and the un-removed first material layer constitutes the tip portions without being removed The divided portion of the substrate constitutes the bottom portions. The method for manufacturing a field emission structure according to claim 12, further comprising: Before forming the carbon nanotubes, a dielectric material layer and a conductive material layer are sequentially formed on the substrate; and a portion of the conductive material layer and a portion of the dielectric material layer are removed to form on the substrate. a gate and a patterned dielectric layer, wherein the patterned dielectric layer has an opening to accommodate the nano-tip, and the gate is disposed on the patterned dielectric layer. The method of fabricating a field emission structure according to claim 12, wherein the substrate comprises a semiconductor substrate. The method of manufacturing the field emission structure of claim 12, wherein the substrate comprises: an insulating substrate; an electrode layer disposed on the insulating substrate; and a resistive layer disposed on the electrode layer; And a semiconductor layer disposed on the resistive layer, wherein the first material layer is formed on the semiconductor layer, and the semiconductor layer is partially removed, and the unselected portion of the semiconductor layer constitutes each of the nanometers a bottom portion of the tip. The method for manufacturing a field emission structure according to claim 12, wherein each of the nanometer cones comprises a bottom portion disposed on the substrate and a tip portion located above the bottom portion, wherein each of the tips In the step of forming a plurality of carbon nanotubes on the tip of the nanometer: if the carbon nanotubes grow on the surface of the tip portions, the required growth temperature is about 200 degrees Celsius to 1000 degrees Celsius. And if the carbon nanotubes grow on the surface of the bottom portions, the required growth temperature is about 450 degrees Celsius to 1000 degrees Celsius.