JPH11176316A - Cathode element for field emission type vacuum element, field emission type vacuum element and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sturdy field emission type vacuum element having high reliability, and a long life. SOLUTION: In this vacuum element an emitter 11 containing a large number of needle-like electrodes 14 and a gate electrode 16 is arranged on a substrate 13, an energizing bar 37 applying potential to the gate electrode 16 through a hole formed in the substrate 13 is extracted from the gate electrode 16, an anode 20 is confronting arranged apart predetermined spacings from the emitter 11, and these are sealed in a vacuum sealed vessel 50. Thereby, mechanically and electrically stable and reasonable structure is obtained, and reliability on airtightness required for maintaining high vacuum for a long period is also high.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cathode device for a field emission type vacuum device, a field emission type vacuum device, and a method of manufacturing the same.

[0002]

2. Description of the Related Art A field emission type vacuum element controls current by utilizing electron emission under a strong electric field.
"IEEJ Magazine Vol. 112, No. 4, pp. 257 (1992)"
The basic principle is explained here.

As shown in FIG. 12, an emitter 1 has a sharp needle-like electrode 2, and a plate-like anode 3 is provided opposite to the sharp needle-like electrode. When a positive voltage V is applied to the anode 3 with respect to the emitter 1, a strong electric field is applied to the tip of the needle-shaped electrode 2, and high-density electrons are emitted therefrom. This phenomenon is generally called "field emission". Therefore, a gate electrode 4 is further provided on the front surface of the emitter 1 (a hole 5 is formed near a portion of the gate electrode 4 facing the tip of the needle electrode 2). When the voltage Vg is made positive, the electron emission from the needle electrode 2 becomes intense, but when the voltage Vg is made zero or negative, the electron emission from the tip of the needle electrode 2 is weakened and stops.

If this characteristic is used, the amount of electrons emitted from the needle electrode 2 can be adjusted by the voltage applied to the gate electrode 4, and the current I can be controlled using this. That is, the same operation as the triode vacuum tube is performed.

However, since the current from one needle-like electrode is extremely small, it is necessary to increase the current by integrating a large number of such currents for power use. In order to manufacture an emitter in which a large number of needle-shaped electrodes are integrated, for example, as disclosed in Japanese Unexamined Patent Publication No. Hei 6-131970, a microfabrication method developed for manufacturing a semiconductor is disclosed. Technology available. FIG. 13 illustrates a combined structure of the needle electrode and the gate electrode manufactured as described above. In this structure, for example, the needle-shaped electrode 2 is provided on a substrate 6 made of silicon (Si) by vapor deposition or etching, and an insulating layer 7 made of, for example, silica (SiO 2) is mounted on the substrate 6. The gate electrode 4 is mounted on the insulating layer 7. The diameter of the hole 5 of the gate electrode 4 and the thickness of the insulating layer 7 are on the order of 1 micron according to the present technology, and
They are placed on a large number.

[0006]

In order to use such a field emission type vacuum element for a high power control application, an emitter having an enormous number of microneedle electrodes is combined with an anode and arranged in a high vacuum. Must. It is also desirable that the gate terminal be mechanically robust, have a highly reliable structure without the risk of damaging the vacuum by leakage, and be easily assembled.

SUMMARY OF THE INVENTION The present invention has been made to solve such technical problems, and is easy to assemble and has high reliability for a cathode device for a field emission vacuum device for electric power, a field emission vacuum device, and a method of manufacturing the same. The purpose is to provide.

Another object of the present invention is to provide a field emission type vacuum element for power having a long life and a method for manufacturing the same.

[0009]

According to a first aspect of the present invention, there is provided a cathode device for a field emission type vacuum device, wherein a substrate on which an emitter including a large number of needle-like electrodes and gate electrodes are mounted is loaded on a current-carrying member. Provided with a current lead-out terminal
It is easy to conduct electricity between terminals connected to external circuits, and has a mechanically strong structure.

A field emission type vacuum element according to a second aspect of the present invention comprises:
The cathode element and the anode according to claim 1 are housed in an insulating container such that the anode and the emitter face each other at a predetermined interval, and the cathode element according to claim 1 is used to form a predetermined interval between the emitters. Opening and arranging the anode, the conductive member of the anode and the emitter, and the end of the anode-side opening and the end of the emitter-side opening of the surrounding insulating container are hermetically joined by a sealing metal, The space between the emitter from which electrons are emitted and the anode can be maintained in a vacuum.

According to a third aspect of the present invention, in the field emission type vacuum element of the second aspect, as the surrounding insulating container, two insulating cylinders are cascaded and joined in an airtight manner, and the emitter is connected to the cascaded junction. An intermediate metal fitting is provided in contact with the gate electrode, and a gate terminal connected to the intermediate metal fitting is drawn out of the surrounding insulating container. It is easy and mechanically robust.

According to a fourth aspect of the present invention, in the field emission type vacuum element of the third aspect, the gate electrode and the intermediate metal fitting are connected by an elastic conductor or a flexible conductor. And high reliability.

According to a fifth aspect of the present invention, in the field emission type vacuum element of the third or fourth aspect, a sealing metal joined to an end of the opening on the anode side of the outer insulating container and the inside of the outer insulating container. The bellows is used for airtight connection between the anode and the anode, and the position of the anode can be adjusted. It will be easier.

According to a sixth aspect of the present invention, in the field emission type vacuum element of the fifth aspect, an anode fixing plate is arranged outside a sealing metal joined to an end of the anode side opening of the surrounding insulating container. An anode current-carrying rod joined to the anode is connected to the center of the anode fixing plate, and a spacer having a desired thickness is interposed between the sealing metal and the anode fixing plate. The anode can be easily set at a desired position by selecting the thickness of the anode.

According to a seventh aspect of the present invention, in the field emission type vacuum element of the sixth aspect, a heat radiation member is provided on the anode fixing plate, so that overheating of the anode can be prevented.

The field emission type vacuum element according to the invention of claim 8 is:
A large number of needle-shaped electrodes and an emitter including a gate electrode are arranged on a substrate, and a current-carrying rod for applying a potential to the gate electrode through a hole formed in the substrate is pulled out of the gate electrode, and the emitter is connected to the emitter. The anodes are arranged facing each other at a predetermined interval, and these are sealed in a vacuum-sealed container.The structure is mechanically, electrically stable and reasonable.
The reliability of airtightness for maintaining a high vacuum for a long time can also be improved.

According to a ninth aspect of the present invention, in the field emission type vacuum element of the eighth aspect, a shield is arranged on an outer peripheral portion of the vacuum sealed container so as to surround a space sandwiched between the emitter and the anode. This prevents the problem that the metal vapor adheres and solidifies on the inner surface of the vacuum-sealed container to impair the insulation performance.

According to a tenth aspect of the present invention, in the field emission type vacuum device of the ninth aspect, the shield is supported on the substrate on the emitter side or the anode side.

According to an eleventh aspect of the present invention, in the field emission type vacuum element of the ninth aspect, the shield is supported on an inner wall of the vacuum sealed container.

In the field emission type vacuum element according to the tenth and eleventh aspects of the present invention, the shield can be easily and firmly attached, and the insulation performance can be maintained for a long time.

According to a twelfth aspect of the present invention, in the field emission type vacuum element of the ninth to eleventh aspects, a getter is provided at an arbitrary position in a space between the shield and the inner wall of the vacuum sealed container.

According to a thirteenth aspect of the present invention, in the field emission type vacuum element of the twelfth aspect, the getter is provided on an outer surface of the shield.

The invention of claim 14 is the invention of claim 12 or 13
In the field emission type vacuum element described above, the getter is provided on one or both of members located at upper and lower bottoms of a space between the shield and the inner wall of the vacuum sealed container.

In the field emission type vacuum element according to the present invention, the field emission performance and the insulation performance are not impaired.
For this purpose, a getter can be attached without requiring an extra space, and a high vacuum can be maintained for a long time to extend the product life.

According to a fifteenth aspect of the present invention, in assembling the field emission type vacuum element according to any one of the eighth to fourteenth aspects, one lid plate is hermetically bonded to the anode, and The other lid plate is joined, the emitter and the anode are inserted into the vacuum sealed container, and the openings at both ends of the vacuum sealed container are joined with the one lid plate and the other cover plate, A field-emission vacuum element that can be easily assembled and maintain a high vacuum for a long time can be manufactured.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a sectional structure of a cathode device for a field emission type vacuum device according to a first embodiment of the present invention. Cathode element 1 for field emission type vacuum element of this embodiment
Numeral 0 denotes a structure in which the emitter 11 is mounted on the upper surface of the conducting member 12. The emitter 11 has a structure in which a large number of needle electrodes 14, an insulating layer 15, and a gate electrode 16 are stacked on a substrate 13. The gate electrode 16 has a large number of holes 17 for emitting electrons at a portion facing the needle electrode 14.

The current-carrying member 12 is made of, for example, a conductive material such as oxygen-free copper. The substrate 13 of the emitter 11 is bonded to the upper surface of the conductive member 12 by a conductive bonding material, for example, silver solder or solder. I have. A connection terminal 1 for connecting a conductor on the side of the emitter 11 is provided below the conducting member 12.
8 are provided.

As a result, in the cathode device 10 for a field emission type vacuum device of this embodiment, electrical and mechanical connection between the connection terminal 18 for connection to an external circuit and the emitter substrate 13 can be extremely easily achieved. In addition, since the emitter 11 is mounted on the strong metal energizing member 12 and is firmly joined, it is mechanically and strongly protected.
The structure, shape, and size of the connection terminal 17 can be freely designed as long as the desired function is achieved. For example, as shown in FIG.
9 may be provided, and the external conductor may be screwed using this.

Next, a field emission vacuum device according to a second embodiment of the present invention will be described with reference to FIG. The field emission vacuum device of this embodiment uses the cathode device 10 shown in FIG. 1 or FIG.
An anode 20 is disposed opposite to the anode 20 via a predetermined space A, and an outer insulating container 24 in which an upper insulating tube 21 and a lower insulating tube 22 are cascade-joined with an intermediate metal fitting 23 therebetween is disposed around the anode 20. The anode side sealing fitting 25 of the surrounding insulating container 24 is connected to the anode 20.
, And the cathode-side sealing metal fitting 26 of the outer insulating container 24 is airtightly bonded to the periphery of the current-carrying member 12 of the cathode element 10, and further from the intermediate metal fitting 23 of the outer insulating container 24 to the outside. In this structure, the gate terminal 27 is drawn out.

The outer insulating container 24 is preferably made of alumina porcelain from the viewpoint of the reliability of hermetic bonding with metal, but is not limited thereto, and other porcelain or synthetic resin may be used.

In assembling the field emission type vacuum element of this embodiment, the outer insulating container 24 having the above structure is used.
The anode 20 is fitted into the opening 28 of the anode-side sealing fitting 25 up to the stepped portion 29, and the cathode element 10 is inserted into the opening 30 of the cathode-side sealing fitting 26 of the surrounding insulated container 24 and the step of the current-carrying member 12. This is performed by fitting into the part 31 and joining them airtightly.

The interior of the surrounding insulating container 24 must be finally evacuated to a high vacuum. For this purpose, a joining process is performed in a high vacuum using a process of melting a brazing metal in a vacuum heating furnace. And a method of sealing the exhaust hole after exhausting from an exhaust hole (not shown) provided in advance after assembly.

Also, since the metal and the insulating material have different coefficients of thermal expansion, residual stress remains at the joint after joining, and the mechanical strength may be weakened. It is preferable to join them via sealing metal fittings 25 and 26 instead of joining them directly. In this case, if alumina porcelain is used for the insulating cylinders 21 and 22, the sealing fittings 25 and 26 are made of a metal whose coefficient of thermal expansion is close to that of alumina porcelain, such as iron / cobalt. Nickel-cobalt alloys can be used.

The connection between the gate electrode 16 of the emitter 11 and the intermediate metal member 23 sandwiched between the outer insulating containers 24 is not particularly limited as long as a desired function is achieved. However, from the viewpoint of ease of assembly and reliability, it is preferable to make connection using an elastic conductor or a flexible conductor. FIGS. 4A and 4B illustrate such a preferred connection method.

In the connection example shown in FIG. 4A, a contact portion 33 of the intermediate metal fitting 23 which is in contact with the gate electrode 16 has elasticity, and is pressed against the gate electrode 16 by its spring action. In addition, the contact portion 34 on the gate electrode 16 side needs to be mechanically strong enough to withstand the pressure contact force and electrically needs to be a metal having sufficiently low contact resistance. Can be pasted or silver plated. FIG.
In the connection example (B), the intermediate fitting 23 and the gate electrode 16 are connected using a flexible connection conductor 35.

Next, a field emission vacuum device according to a third embodiment of the present invention will be described with reference to FIG. In this type of field emission vacuum element, it is necessary to adjust the distance between the anode 20 and the emitter 11 to a desired size according to the use conditions. To address such a demand, FIG.
1 shows a field emission type vacuum element having a structure in which a distance d between 0 and an emitter 11 can be freely adjusted.

The field emission type vacuum element of the third embodiment has basically the same structure as the field emission type vacuum element of the second embodiment shown in FIG. Is provided on the center upper surface of the anode 20 with an energizing shaft 41.
1, a fixing plate 42 is attached to the upper end, and the energizing shaft 41 is passed through the opening 28 of the anode-side sealing metal fitting 25 of the surrounding insulating container 24, so that the space between the fixing plate 42 and the anode-side sealing metal fitting 25 is formed. By interposing a spacer 43 having a desired thickness
The distance d between the anode 20 and the emitter 11 is adjusted. In order to make the inside of the surrounding insulating container 24 high vacuum, the bellows 44 connects between the opening 28 of the anode-side sealing metal fitting 25 and the anode-side base of the current-carrying shaft 41 to keep the inside airtight. ing.

Since the inside of the surrounding insulating container 24 is in a vacuum, the anode 20 is pushed by the atmosphere and pulled inside, that is, pulled downward in the drawing, so that the spacer 43 is held even if it is simply sandwiched. However, if necessary, the distance d may be fixed to the fixing plate 42 or the sealing metal 25 and adjusted with a screw.

The temperature of the anode 20 rises due to collision of electrons emitted from the emitter 11 and Joule heat in the conductor. Heat sink (radiation fin)
45 to cool the current-carrying shaft 41 so that the anode 20
Overheating can be suppressed.

Next, a field emission vacuum device according to a fourth embodiment of the present invention will be described with reference to FIG. The field emission type cathode element 10 for a vacuum element has substantially the same structure as the cathode element of the first embodiment shown in FIG. 1, and an emitter 11 is mounted on the upper surface of a disk-shaped current-carrying member 12. The emitter 11 has a large number of needle electrodes 1 on a disk-shaped substrate 13.
4, an insulating layer 15 and a gate electrode 16.

The current-carrying member 12 is made of a conductive material such as oxygen-free copper. The substrate 13 of the emitter 11 is bonded to the upper surface of the current-carrying member 12 by a conductive bonding material, for example, silver solder or solder. I have. An energizing terminal 36 is provided on the lower surface of the energizing member 12. In addition, the conducting member 1
A cover plate 54 is joined to the lower surface of the second member 2.

A through-hole is formed in the center of the substrate 13 of the emitter 11, a current-carrying rod 37 is passed therethrough, the tip of which is connected to the gate electrode 16, and a gate terminal 38 at the rear end. Is provided. Around the power rod 37,
An insulating tube 39 for insulating the gate electrode 16 from the needle electrode 14 is provided. The insulating tube 39 is made of porcelain or synthetic resin, and has sealing fittings 39a, 39b attached to both ends for hermetically joining with a metal. The ends are hermetically joined to the gate terminals 38, respectively.

An anode 20 is arranged on the emitter 11 side of the cathode element 10 with a predetermined space therebetween. Anode 2
A cover plate 53 is joined to the periphery of the zero.

The anode 20 and the cathode element 10 seal the openings at both ends of the hollow insulator tube 50. A joining metal fitting 51 is provided at the opening on the anode side of the insulator tube 50, and a joining metal fitting 52 is provided at the opening portion on the cathode side. The anode 20 and the cathode element 10 are inserted into the openings at both ends of the insulator tube 50, respectively. 5
The porcelain tube 50 is sealed with the anode 20 and the cathode element 10 by abutting and joining the inner and outer peripheral portions of the joint fittings 51 and 52 respectively. In order to make the inside of the insulator tube 50 a high vacuum, air is exhausted through an exhaust tube 55 provided on the cover plate 53 on the anode 20 side, and then the exhaust tube 55 is closed.

The conductors 56, 57 and 58 are connected to the anode 20, the current supply terminal 36 and the gate terminal 38, respectively.

The field emission type vacuum element of the fourth embodiment has a mechanically and electrically stable and reasonable structure.
Airtight reliability for maintaining a high vacuum for a long time is also high.

Next, a fifth embodiment of the present invention will be described with reference to FIG. In the case of the field emission type vacuum element shown in FIG. 6, the tip of the needle electrode 14 for emitting electrons of the emitter 11 has a high current density when energized, and is heated by Joule heat during energization, and Steam is generated. Then, the metal vapor diffuses and reaches the inner surface of the hollow insulator tube 50, and when it adheres there, it is cooled and solidified. This may accumulate over a long period of time to form a metal coating, which may impair the insulation performance.

Therefore, in the field emission type vacuum device of the fifth embodiment shown in FIG. 7, in order to trap metal vapor, a space A sandwiched between the emitter 11 and the anode 20 is surrounded. It is characterized in that a shield 60 is provided on the outer peripheral portion. Other components are the same as those of the field emission type vacuum device of the fourth embodiment shown in FIG. 6, and therefore, the same portions are denoted by the same reference numerals.

In the field emission type vacuum device of the fifth embodiment, the shield 60 is attached to the energizing member 12 of the cathode device 10.

As a result, most of the metal vapor diffused into the space A between the emitter 11 and the anode 20 is shielded.
And solidifies, and the inner surface of the insulator tube 50 can be protected.

The place where the shield is attached is not particularly limited, and the shield can be attached to the anode 20 side like the shield 61 shown in FIG. Further, as in the case of the shield 62 shown in FIG. 9, a structure in which the protrusion 63 is provided on the inner periphery of the insulator tube 50 and the shield 62 is attached thereto may be used. The means for attaching these shields 60, 61, 62 is not particularly limited.
Adhesion or welding means can be used.

Next, a field emission vacuum device according to a sixth embodiment of the present invention will be described with reference to FIG. When manufacturing a field emission type vacuum element, the inside of the insulator tube 50 should be kept at a high vacuum if the inside is evacuated to a high vacuum after assembly, and then the exhaust pipe 55 is sealed. If the exposed member has gas molecules attached to its surface or occluded inside, it will diffuse and desorb into a high vacuum over time. Therefore, the high vacuum may deteriorate. In order to suppress the vacuum from being deteriorated due to such a cause, a getter for adsorbing gas molecules may be attached inside. However, when the charged particles collide with the getter, the getter releases the gas molecules that have been adsorbed. Also, if the metal vapor adheres and solidifies on the surface of the getter, the activated surface may be covered with the adhered metal, and the ability to adsorb gas molecules may be impaired. Therefore, when the getter is attached, it is desirable that there is no such a concern, and that the getter is attached to a place where the space is not particularly necessary for attaching the getter.

The field emission type vacuum element according to the sixth embodiment of the present invention was invented based on such considerations.
As shown in FIG. 10, a getter is additionally provided on the inner surface of the anode-side cover plate 53 (getter 71) and the inner surface of the emitter-side cover plate 54 (getter 7) with respect to the field emission vacuum device having the structure of FIG.
2) and is attached to the outer surface (getter 73) of the shield 60.

As described above, the getters 71, 72, 73 can maintain a high degree of vacuum for a long period of time by adsorbing the gas molecules released into the vacuum insulator tube 50, so that the field emission type vacuum can be maintained. The life of the device is improved.

The required amount of the getter is a vacuum insulator 50.
It is determined by the parts material inside and the processing before assembly,
If only a small amount is required, it may be provided at one or two of these positions instead of being mounted at all three positions as shown in FIG.

In the embodiment of FIG. 10 described above, FIG.
Although a getter is further attached to the field emission type vacuum device of FIG. 1, the present invention is not limited to this. For the field emission type vacuum device shown in FIG. 8 and the field emission type vacuum device shown in FIG. The getter can be attached in almost the same manner.

Next, a method of manufacturing a field emission vacuum device according to a seventh embodiment of the present invention will be described with reference to FIG. The method for manufacturing the field emission vacuum device according to the seventh embodiment is a method for manufacturing the field emission vacuum device according to the sixth embodiment shown in FIG. The anode element 40 side, the cathode element 10 side, and the hollow insulator tube 50 are assembled in advance. That is, on the anode element 40 side, the cover plate 5
The anode 20, the open exhaust pipe 55, and the getter 71 are joined to the cathode element 3, and the cover plate 54 is previously provided on the cathode element 10 side.
Current-carrying member 12 having emitter 11 mounted thereon, current-carrying shaft 37,
All parts such as the insulating tube 39 and the shield 60 are joined in advance, and the metal fittings 51 and 52 are joined to the insulator tube 50 in advance.

Then, these three members are combined to form a cover plate 53.
Of the outer edge of the porcelain tube 50 is hermetically joined to a metal fitting 51 of the insulator tube 50, and the outer edge tip portion of the lid plate 54 is attached to the metal fitting 52 of the insulator tube 50.
Airtightly joined. For this joining, generally used hermetic joining means such as welding, brazing (soldering), and bonding are used.

Finally, the exhaust pipe 55 is connected to a vacuum pump to evacuate the inside of the insulator tube 50 to a sufficiently high vacuum.
By compressing and closing the exhaust pipe 55, a field emission vacuum element is completed.

In this way, it is possible to manufacture a field-emission vacuum element that is structurally simple, has high operation reliability, is robust, and has a long life.

The method of manufacturing the field emission type vacuum element according to the seventh embodiment includes three steps: the anode side, the cathode element side, and the insulator tube.
It is characterized by assembling each member in advance, joining them last, and evacuating,
The present invention is equally applicable to the manufacture of each of the field emission vacuum devices shown in FIGS. 7 to 9 without a getter and the manufacture of the field emission vacuum device without a shield shown in FIG.

[0062]

As described above, according to the first aspect of the present invention,
A substrate on which a large number of needle-shaped electrodes and an emitter including a gate electrode are mounted is loaded on a current-carrying member, and a current-leading terminal is provided on the current-carrying member. A cathode device for a field emission type vacuum device having a robust structure is obtained.

According to the second aspect of the present invention, the anode and the emitter of the cathode element are housed in the surrounding insulated container using the cathode element of the first aspect of the invention such that the anode and the emitter of the cathode element face each other at a predetermined interval. Since the current-carrying members of the anode and the emitter are hermetically joined to the end of the opening on the anode side and the end of the opening on the emitter side of the surrounding insulated container by a sealing metal, the emission of electrons in the field emission vacuum element is performed. The space between the emitter and the anode can be maintained in a vacuum.

According to the third aspect of the present invention, as the surrounding insulating container, two insulating cylinders are cascaded and joined in an airtight manner, and the cascaded joint is provided with an intermediate metal fitting which is in contact with the gate electrode of the emitter. Since the gate terminal connected to the intermediate fitting was drawn out of the surrounding insulating container,
The field emission type vacuum element can have a simple structure and can easily supply a current to the gate electrode, and can be made mechanically strong.

According to the fourth aspect of the present invention, since the gate electrode and the intermediate metal member are connected by an elastic conductor or a flexible conductor, the operation of energizing and connecting the gate electrode in the field emission vacuum device is facilitated and reliable. Can be enhanced.

According to the fifth aspect of the present invention, a bellows is used to hermetically connect the sealing metal joined to the end of the opening on the anode side of the surrounding insulating container and the anode in the surrounding insulating container. Since the position of the anode can be adjusted, desired characteristics and characteristics can be obtained while maintaining the inside of the field emission vacuum element in a vacuum.
It is easy to make adjustments to obtain performance.

According to the sixth aspect of the present invention, the anode fixing plate is disposed outside the sealing fitting joined to the end of the anode side opening of the surrounding insulating container, and the anode fixing plate is provided at the center of the anode fixing plate. Since the anode current-carrying rod joined to the anode and the anode fixing plate are interposed, and a spacer having a desired thickness is interposed between the sealing metal and the anode fixing plate, the thickness of the anode in the field emission type vacuum element is selected. Can be easily set at a desired position.

According to the seventh aspect of the present invention, since the heat dissipating member is provided on the anode fixing plate, overheating of the anode in the field emission type vacuum element can be prevented.

According to the eighth aspect of the present invention, an emitter including a large number of needle-like electrodes and gate electrodes is arranged on a substrate, and a current is passed through a hole formed in the substrate to apply a potential to the gate electrode. The rod is pulled out from the gate electrode, the anode is placed opposite to the emitter at a predetermined interval, and these are sealed in a vacuum-tight container, so that the field emission vacuum element is mechanically and electrically stable and has a reasonable structure. Thus, the reliability of airtightness for maintaining a high vacuum for a long time can be improved.

According to the ninth aspect of the present invention, since the shield is disposed on the outer peripheral portion of the vacuum sealed container so as to surround the space between the emitter and the anode, the vacuum sealed container in the field emission type vacuum element is used. Metal vapor adheres to the inner surface of the
Prevents the problem of solidification and impairing insulation performance,
The life can be extended.

According to the tenth and eleventh aspects of the present invention, the shield can be easily and firmly attached in the vacuum sealed container of the field emission type vacuum element, and the insulation performance can be maintained for a long time.

According to the twelfth to fourteenth aspects of the present invention, the getter is mounted in the vacuum sealed container without impairing the field emission performance and insulation performance of the field emission type vacuum element and without requiring an extra space. In addition, it is possible to maintain the high vacuum for a long period of time and extend the product life of the field emission vacuum device.

According to the fifteenth aspect of the present invention, when assembling the field emission type vacuum element, one cover plate is airtightly joined to the anode, the other cover plate is joined to the emitter, and the emitter and the vacuum sealed container are joined to each other. Since the anode is inserted and the openings at both ends of the vacuum-sealed container are joined by one lid plate and the other lid plate, the assembly work of the field emission vacuum element is easy and high vacuum can be maintained for a long time. A field emission vacuum device can be manufactured.

[Brief description of the drawings]

FIG. 1 is a sectional view of a cathode device for a field emission type vacuum device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of a modification of the cathode device according to the first embodiment.

FIG. 3 is a sectional view of a field-emission vacuum device according to a second embodiment of the present invention.

FIG. 4 is an explanatory diagram showing an electrical connection between a gate electrode and an intermediate metal fitting in the field emission vacuum device according to the second embodiment.

FIG. 5 is a sectional view of a field-emission vacuum device according to a third embodiment of the present invention.

FIG. 6 is a sectional view of a field-emission vacuum device according to a fourth embodiment of the present invention.

FIG. 7 is a sectional view of a field emission type vacuum element according to a fifth embodiment of the present invention.

FIG. 8 is a sectional view showing a modification of the field emission vacuum device of the fifth embodiment.

FIG. 9 is a sectional view showing another modified example of the field emission vacuum element of the fifth embodiment.

FIG. 10 is a sectional view of a field emission type vacuum element according to a sixth embodiment of the present invention.

FIG. 11 is an explanatory diagram of a method for manufacturing a field emission vacuum device according to a seventh embodiment of the present invention.

FIG. 12 is an explanatory diagram of the operation principle of a general field emission vacuum element.

FIG. 13 is a structural view of a general field emission type vacuum element.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Cathode element 11 Emitter 12 Current-carrying member 13 Substrate 14 Needle electrode 15 Insulating layer 16 Gate electrode 17 Hole 18 Terminal 20 Anode 21 Insulating cylinder 22 Insulating cylinder 23 Intermediate fitting 24 Surrounding insulating container 25 Sealing fitting 26 Sealing fitting 27 Gate Terminal 33 Contact part 34 Contact part 35 Connection conductor 36 Terminal 37 Power supply rod 38 Gate terminal 39 Insulation tube 40 Anode element 41 Current supply shaft 42 Fixing plate 43 Spacer 44 Bellows 45 Heat sink 50 Insulator tube 51 Metal fitting 52 Metal fitting 53 Cover plate 54 Cover plate 55 Exhaust Tube 60-62 Shield 71-73 Getter

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Kiyoshi Nanbu 1 Toshiba-cho, Fuchu-shi, Tokyo Toshiba Corporation Fuchu Plant

Claims (15)

[Claims] 1. A cathode device for a field emission vacuum device, comprising: a substrate on which a plurality of needle electrodes and an emitter including a gate electrode are mounted on a current-carrying member; and a current lead-out terminal provided on the current-carrying member. 2. The cathode element and the anode according to claim 1 are accommodated in an insulating container such that the anode and the emitter face each other at a predetermined interval, and are provided with a current-carrying member for the anode and the emitter. A field-emission vacuum element in which an end of the opening on the anode side and an end of the opening on the emitter side of the outer insulating container are hermetically joined by a sealing metal. 3. An intermediate metal fitting for airtightly cascading and joining two insulating cylinders as the surrounding insulating container, and providing an intermediate metal fitting in contact with the gate electrode of the emitter at the cascaded connecting part, and connecting to the intermediate metal fitting. 3. The field emission vacuum device according to claim 2, wherein a gate terminal drawn out of the surrounding insulating container is used. 4. The field emission vacuum device according to claim 3, wherein said gate electrode and said intermediate metal member are connected by an elastic conductor or a flexible conductor. 5. A bellows is used to hermetically connect a sealing metal joined to an end of the opening on the anode side of the surrounding insulated container and the anode in the surrounding insulated container by a bellows. The field emission type vacuum element according to claim 3 or 4, wherein the position can be adjusted. 6. An anode fixing plate is disposed outside a sealing metal joined to an end of an opening on the anode side of the surrounding insulating container,
An anode current-carrying rod joined to the anode is connected to a center portion of the anode fixing plate, and a spacer having a desired thickness is interposed between the sealing metal and the anode fixing plate. Item 6. A field emission vacuum device according to item 5. 7. The field emission vacuum device according to claim 6, wherein a heat radiation member is provided on the anode fixing plate. 8. A plurality of needle-like electrodes and an emitter including a gate electrode are arranged on a substrate, and a current-carrying rod for applying a potential to the gate electrode through a hole formed in the substrate is provided from the gate electrode. An electric field discharge type vacuum element comprising an anode, which is drawn out, an anode is arranged opposite to the emitter at a predetermined interval, and these are sealed in a vacuum sealed container. 9. The field emission vacuum according to claim 8, wherein a shield is arranged on an outer peripheral portion of the vacuum sealed container so as to surround a space sandwiched between the emitter and the anode. element. 10. The field emission vacuum device according to claim 9, wherein the shield is supported by the substrate on the emitter side or the anode side. 11. The field emission vacuum device according to claim 9, wherein the shield is supported on an inner wall of the vacuum sealed container. 12. The field emission vacuum device according to claim 9, wherein a getter is provided at an arbitrary position in a space between the shield and the inner wall of the vacuum sealed container. 13. The field emission vacuum device according to claim 12, wherein the getter is provided on an outer surface of the shield. 14. The device according to claim 9, wherein the getter is provided on one or both of members located at upper and lower bottoms of a space between the shield and the inner wall of the vacuum sealed container. 3. A field emission vacuum element according to claim 1. 15. When assembling the field emission vacuum device according to any one of claims 8 to 14, one lid plate is airtightly joined to the anode, and the other lid plate is joined to the emitter. Insert the emitter and anode in a sealed container,
A method for manufacturing a field emission type vacuum element, wherein openings at both ends of the vacuum sealed container are joined with the one lid plate and the other lid plate.