JP3152018B2 - Method of manufacturing field emission device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-emitting display device, a light source for a printer, an electron microscope, an electron beam exposure apparatus, and a CRT.
The present invention relates to a method for manufacturing a field emission device that can be used as an electron source for various electron beam applied devices such as an electron gun for use, a microwave amplification tube, and a sensor.

[0002]

2. Description of the Related Art As a conventional field emission device, a so-called Spindt type cathode, which has been announced as a microchip display by SRI in the United States and LETI in France, is known. 3A to 3F show an example of a procedure for manufacturing a Spindt-type cathode.

[0003] As shown in FIG.
An insulating layer 101 made of a thermal oxide film is formed thereon, and a gate layer 102 made of Nb is formed thereon.

[0004] As shown in FIG.
A resist 103 is applied on the substrate 02 and exposed through a mask (not shown), followed by development to form a hole 104 having a predetermined pattern.

[0005] As shown in FIG. 3 C, an opening 105 is formed in the gate layer 102 by RIE using SF ₆ or the like.
Subsequently, the insulating layer 101 is etched with BHF to form a hole 106 reaching the Si substrate 100.

[0006] As shown in FIG.
An Al release layer 107 is formed thereon by oblique evaporation. That is,
Al is obliquely vapor-deposited at a shallow angle of incidence substantially parallel to the Si substrate 100 with respect to the central axis X of the opening 105 to the hole 106 perpendicular to the Si substrate 100 and the release layer 10 is formed on the gate layer 102.
7 is formed.

[0007] As shown in FIG.
Mo, which is an emitter material, is vapor-deposited from above vertically to form a cone-shaped emitter 108 on the Si substrate 100 in the hole 106.

As shown in FIG. 3F, Mo deposited on the gate layer 102 together with the release layer 107 is removed, and the field emission device is completed.

[0009]

The above-mentioned conventional manufacturing method has the following problems. 1) The Al release layer 107 must be formed by oblique evaporation. This is because the holes 1
This is to prevent Al from entering into the area 06. If A
This is because if l is vapor-deposited in the hole 106, the emitter 108 is also peeled off in the Al peeling step after the emitter 108 is manufactured. However, this oblique deposition method,
When the film quality of Al changes depending on the angle, and particularly when the crystal state of the opening changes, it affects the formation of the emitter 108 that determines the field emission characteristics, so that the uniformity, reproducibility, and insulation yield of the emission characteristics of the cathode are obtained. Affect
Very poor reproducibility. In addition, when manufacturing a large field emission substrate such as an electron source for a display, the deposition apparatus is extremely large in principle, and if the distance between the deposition source and the substrate is not sufficient, the Al is obliquely formed at a uniform angle. It cannot be deposited. For this reason, the oblique vapor deposition method uses a large amount of vapor deposition material, and is not suitable for mass production in terms of increasing the size of the apparatus.

2) In the conventional process of forming the opening 105 of the gate layer 102, the hole diameter of the opening 105 is patterned and N
Holes are formed in the b film by RIE using SF ₆ or the like, and then holes 106 are formed in the insulating layer 101 of SiO ₂ to the Si substrate 100 by buffer hydrofluoric acid or the like in a wet etching method or by CHF _{3 in a} dry etching method. Was carved upright. However, in this step, F and their compounds remain on the gate layer 102, in the crystal grain boundaries of the gate layer 102, and on the surface of the insulating layer 101 and the like inside the holes 106. Due to the complicated structure of the cathode substrate, these substances are difficult to completely remove in a later process, and finally are released from each of the parts when the cathode emits an electron beam, and gas adsorbed contaminants to the emitter are emitted. And adversely affect the life characteristics of the field emission device.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a field emission device capable of manufacturing a field emission device excellent in reproducibility, uniformity, and mass productivity even on a large-sized substrate.

[0012]

According to a first aspect of the present invention, there is provided a method of manufacturing a field emission device, comprising the steps of: forming a substrate; an insulating layer provided on the substrate; and a hole formed in the insulating layer. An emitter electrode provided on the substrate, and a method for manufacturing a field emission device including a gate electrode formed on an upper surface of the insulating layer and having a gate hole corresponding to the hole, wherein an insulating layer is provided on the substrate. Forming a gate electrode and a peeling layer by sequentially laminating them; forming a resist layer on the surface of the peeling layer to form an opening in the resist layer; and forming a gas through the peeling layer, the gate electrode, and the insulating layer. Forming the gate hole and the hole by processing with a cluster ion beam; depositing an emitter material from the release layer side to form an emitter electrode in the hole; Emitter material It is characterized by having a step of removing with the release layer.

According to a second aspect of the present invention, there is provided a method for manufacturing a field emission device, wherein a substrate, a first insulating layer provided on the substrate, and a hole formed in the first insulating layer. An emitter electrode provided on the substrate, a gate electrode formed on the upper surface of the first insulating layer and having a gate hole corresponding to the hole, and a gate electrode formed on the upper surface of the gate electrode and In a method for manufacturing a field emission device including a second insulating layer in which corresponding holes are formed, and a focusing electrode formed on an upper surface of the second insulating layer, a first insulating layer is provided on the substrate. Forming a gate electrode, a second insulating layer, a focusing electrode, and a release layer by sequentially laminating them; forming a resist layer on the surface of the release layer to form an opening in the resist layer; Layer, focusing electrode, second insulating layer, gate electrode and first Processing the edge layer with a gas cluster ion beam to form the holes; depositing an emitter material from the release layer side to form an emitter electrode in the holes; A step of removing the attached emitter material together with the release layer.

According to the present invention, in each of the above methods, the substrate may include a cathode electrode, or may include a cathode electrode and a resistive layer.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1 (a), an insulating layer 2 made of an oxide film of SiO ₂ on the surface of the Si substrate 1, to form the gate layer 3 as a gate electrode made of Nb film thereon. On the gate layer 3, a release layer 4 made of aluminum is formed by vacuum deposition or sputtering.

As shown in FIG. 1B, a resist layer 5 is applied on the release layer 4 and developed after exposure through a mask (not shown) to form an opening 6 having a predetermined pattern.

Using the resist layer 5 in which the openings 6 of the predetermined pattern are formed as a mask, etching is performed by a gas cluster ion beam until the surface of the Si substrate 1 is exposed as shown in FIG. Two holes 7 and gate holes 8 of the gate layer 3 corresponding to the holes 7 are formed. If the resist layer 5 is left on the peeling layer 4 after the completion of the etching, over-etching can be prevented.

FIG. 2 shows a gas cluster ion beam apparatus 11 used in the step of FIG. The inside of the substantially cylindrical main body 12 is evacuated to a high vacuum state by exhaust means 13, 14, 15. The introduction portion 16 at one end of the main body 12 has a thin nozzle with an inner diameter of about 0.1 mm or less, and gas is injected from the nozzle into the main body 12 at a pressure of several atmospheres. . Then, this gas is guided to the cluster generation unit 17 and the ionization unit 18. The gas cluster ions formed here are accelerated through deflection systems 19 and 19, a lens system 20, a mass separation system 21 and an accelerating tube 22, and the Si substrate 1 as a target provided at the other end in the main body 12 Is irradiated.

Here, in the gas cluster ions irradiated to the Si substrate 1, one of the atoms constituting the cluster has an electric charge. That is, since one atom of a group of hundreds to thousands of atoms is ionized, the gas cluster ions act on the target as a mass having a mass several hundred to several thousand times. In this case, the atoms constituting the cluster are weakly bonded to each other, and if the number is N, the energy becomes 1 / N and the charge-mass ratio becomes 1 / N. Can be

Therefore, when the gas cluster ion beam is used in the etching process of the insulating layer 2 and the gate layer 3 in the present manufacturing method, the following effects can be obtained. 1) Irradiation can be performed with a low energy beam of several eV to several hundred eV. 2) A large amount of atoms can be transported with a small current. 3) Insulating material can be etched. 4) A high sputtering rate is obtained (100 times or more). 5) As the etching gas, a gas having low reactivity or adsorptivity such as Ar, CO ₂ , N ₂ can be used.

Next, after removing the remaining resist layer 5, Mo as an emitter material is vapor-deposited on the Si substrate 1 from above vertically by means such as an electron beam vapor deposition method as shown in FIG. Then, a cone-shaped emitter electrode 9 is formed in the hole 7 of the insulating layer 2.

Finally, as shown in FIG. 1E, Mo on the gate layer 3 is removed together with the release layer 4, and the field emission device 10 is completed.

In one embodiment described above, the substrate is S
Although an i-substrate was used, a glass substrate can also be used. In that case, an emitter electrode made of a metal thin film may be provided on the upper surface of the glass substrate, and an insulating layer such as SiO ₂ may be formed thereon by CVD or the like. Further, a resistance layer may be provided between the emitter electrode and each emitter.

The above-described embodiment relates to the field emission device 10 having the structure in which the emitter electrode 9 and the gate layer 3 are formed on the Si substrate 1. It can also be applied to For example, a focusing electrode as a control electrode is provided on the gate layer 3 with a second insulating layer interposed therebetween, and a hole corresponding to the gate hole 8 of the gate layer 3 is formed as a second electrode.
The present invention is also useful for manufacturing a field emission device formed on the insulating layer and the focusing electrode.

In the method for manufacturing such a three-electrode field emission device, first, a first insulating layer, a gate electrode, a second insulating layer, a focusing electrode, and a release layer are sequentially laminated on a substrate. I do. Next, a resist layer is formed on the surface of the release layer, and an opening having a predetermined pattern is formed in the resist layer.
Then, using the resist layer as a mask, continuous holes reaching the substrate are formed in the release layer, the focusing electrode, the second insulating layer, the gate electrode, and the first insulating layer by a gas cluster ion beam.

Through the above steps, the same holes and gate holes as in the first embodiment are formed in the first insulating layer and the gate electrode. Further, holes corresponding to these holes and gate holes are also formed in the second insulating layer, the focusing electrode, and the release layer.

Next, an emitter material is vertically deposited on the substrate from the release layer side to form an emitter electrode in the hole. Finally, the emitter material deposited on the release layer is removed together with the release layer.

[0028]

According to the present invention, a continuous opening reaching a substrate can be easily formed in an insulating layer, a gate electrode or the like laminated on the substrate by using a gas cluster ion beam.

Therefore, unlike the conventional case, it is not necessary to form the peeling layer by the oblique deposition method in which it is difficult to control the film quality, and it is possible to form a peeling layer having a uniform film quality and opening shape over the entire surface of a substrate having a large area.

Therefore, the emitter electrode can be formed with good reproducibility, and a field emission device having good characteristics can be formed.
In addition, since the steps and equipment are simplified, mass productivity is excellent. Further, since the gas used for the gas cluster ion beam is a harmless inert gas such as Ar, CO ₂ , and N ₂ , equipment for storing the gas is simple, and the gas is used in the manufacturing process of the field emission device. Can be easily incorporated.

Further, the above-mentioned inert gas used for the gas cluster in-beam does not adversely affect the characteristics of the field emission device, unlike a gas having a high adsorptivity and reactivity such as halogen. Therefore, the step of cleaning the opening can be simplified or unnecessary.

[Brief description of the drawings]

FIG. 1 is a process chart showing one embodiment of the present invention.

FIG. 2 is a schematic view of a gas cluster ion beam apparatus used in one embodiment of the present invention.

FIG. 3 is a process chart showing an example of a conventional method for manufacturing a field emission device.

[Explanation of symbols]

 Reference Signs List 1 Si substrate as substrate 2 Insulating layer 3 Gate layer as gate electrode 4 Release layer 5 Resist layer 6 Opening 7 Vacancy 8 Gate hole 9 Emitter electrode 10 Field emission device

Claims (4)

(57) [Claims] A substrate, an insulating layer provided on the substrate, an emitter electrode provided on the substrate inside holes formed in the insulating layer, and an upper surface of the insulating layer. A method for manufacturing a field emission device including a gate electrode having a gate hole corresponding to the hole, a step of sequentially laminating and forming an insulating layer, a gate electrode, and a release layer on the substrate; Forming a resist layer on the surface to form openings in the resist layer, and forming the gate holes and holes by processing the release layer, the gate electrode, and the insulating layer with a gas cluster ion beam, Forming an emitter electrode in the hole by depositing an emitter material from the release layer side, and removing the emitter material deposited on the release layer together with the release layer. Release Manufacturing method for the device. 2. A substrate, a first insulating layer provided on the substrate, an emitter electrode provided on the substrate inside a hole formed in the first insulating layer, A gate electrode formed on the upper surface of one insulating layer and having a gate hole corresponding to the hole, and a second insulating layer formed on the upper surface of the gate electrode and having a hole corresponding to the gate hole formed therein And a method of manufacturing a field emission device having a focusing electrode formed on the upper surface of the second insulating layer, wherein the first insulating layer, the gate electrode, the second insulating layer, the focusing electrode, and the Forming a layer by sequentially stacking layers; forming a resist layer on the surface of the release layer to form an opening in the resist layer; and forming the release layer, the focusing electrode, the second insulating layer, and the gate electrode. Before processing the first insulating layer with a gas cluster ion beam Forming a hole, depositing an emitter material from the release layer side to form an emitter electrode in the hole, and removing the emitter material deposited on the release layer together with the release layer A method for manufacturing a field emission device, comprising: 3. The method according to claim 1, wherein the substrate includes a cathode electrode for supplying a current to the emitter electrode. 4. The field emission device according to claim 1, wherein the substrate includes a cathode electrode for supplying a current to the emitter electrode, and a resistive layer formed on an upper surface or a side surface of the cathode electrode. Manufacturing method.