JPH08255557A - Field emission electron source device and manufacture thereof - Google Patents

Abstract

PURPOSE: To provide a field emission electron source device and a method for the manufacture thereof ensuring freedom from a drop in yield or reliability by reducing leak current flowing across a cold cathode and a gate electrode for preventing the breakdown of an electron emission section, or reducing emission current from the cold cathode for preventing operating voltage from reaching a breakdown level. CONSTITUTION: Each electron source of a field emission electron source device includes a cold cathode 10 for emitting electrons, an insulation layer 12, a resistance layer 13, the first gate electrode section 14a and the second gate electrode section 14b. The layer 13 is connected in series to the sections 14a and 14b. According to this construction, leak current, even when liable to flow across the cathode 10 and the gate electrode, is limited with a resistor connected in series to each of the electron source gate electrodes. Thus, a breakdown hardly takes place on an electron emission section.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a field emission type electron source which emits electrons in a high electric field and a method for manufacturing the same, and more particularly to a field emission type electron source device having a cathode and a gate electrode integrated on a substrate and the same. It relates to a manufacturing method.

[0002]

2. Description of the Related Art In recent years, with the progress of microfabrication technology used in the field of integrated circuits or thin films, the progress of manufacturing technology of field emission type electron sources which emit electrons in a high electric field has been remarkable, and particularly extremely. A field emission type electron source device having a field emission type cold cathode having a small structure has been manufactured. The field emission type cold cathode of the electron source device of this kind is the most basic electron emission device among the main parts constituting the triode type micro electron tube or the micro electron gun.

A field-emission electron source device including a large number of electron-emitting portions was devised as a constituent element of, for example, a micro triode or a thin display element. The operation and manufacturing method of the field-emission electron source are described below. , Stanford Research Institute
rch Institute). A. CA of Spindt et al., Journal of Applied Physics (Journal of
Applied Physics, Vol. 47, 12
No. 5248-5263 (December 1976). A. U.S. Pat. No. 4,307,507 and H. Spint et al. F. It is disclosed in US Pat. Nos. 4,307,507 and 4,513,308 by HF Gray et al.

This device, that is, a field emission type electron source device, includes a cold cathode that emits electrons according to the principle of field emission,
The cold cathode is provided with a gate electrode as an electric field applying electrode for applying a positive voltage to apply an electric field to emit electrons.

[0005]

In these field-emission electron sources, in some of the electron-emission parts produced, the leakage current on the surface of the insulating layer due to contamination in the production process. Of the electrons emitted from the cold cathode into the gate electrode due to variations in the shape caused by non-uniformity of the fabrication process, and relatively large leakage current between the cold cathode and the gate electrode. May flow. Due to these leak currents, there is a problem that the electron emission portion is destroyed by the temperature rise due to the generation of Joule heat and the plasma generated by the gas emission.

Further, in these field emission electron sources, since the cold cathode is extremely sharpened in order to reduce the operating voltage, the temperature rise of the tip portion due to the Nottingham effect or Joule heat is likely to occur. The operating voltage is relatively low due to the variation in the shape of the tip of the cold cathode caused by the nonuniformity of the fabrication process, and there is an electron emitting portion which is destroyed at a relatively low operating voltage.

In a field emission type electron source including a large number of electron emitting portions, if a part of the electron emitting portions is destroyed, the cold cathode and the gate electrode are short-circuited in many cases, and the entire electron source functions. It's gone.

The present invention has been made in order to solve the above problems, and reduces the leak current between the cold cathode and the gate electrode so that the electron emitting portion is not destroyed, or An object of the present invention is to provide a field-emission electron source device and a method for manufacturing the same that reduce the emission current from the cold cathode so that the operating voltage does not lead to breakdown, and do not cause a reduction in yield or reliability. To do.

[0009]

A field emission type electron source device according to a first aspect of the present invention includes a resistor connected in series with a gate electrode.

According to another aspect of the field emission type electron source device of the present invention, a cathode for emitting electrons, which is formed of a protruding portion on a substrate made of a semiconductor or a metal, and a protruding tip portion of the cathode are formed on the substrate. An insulating layer formed excluding the above, a resistance layer formed on the insulating layer and in the vicinity of the tip portion of the cathode, and a portion surrounding the tip portion of the cathode on the resistance layer to extract electrons from the cathode A first gate electrode portion and a second gate electrode portion formed separately from the first gate electrode portion on a portion of the resistance layer excluding the first gate electrode portion, To do.

A field emission type electron source device according to a third aspect of the present invention comprises a cathode for emitting electrons, which is composed of a protruding portion on a substrate made of semiconductor or metal, and a protruding tip portion of the cathode on the substrate. In order to extract electrons from the cathode, the insulating layer formed excluding the resistance layer, the resistance layer formed on the insulating layer and in the vicinity of the tip portion of the cathode, and the portion of the resistance layer excluding the portion surrounding the tip portion of the cathode And a formed gate electrode. A field emission type electron source device according to a fourth aspect is characterized in that the resistance layer is made of a non-photoconductive material.

A method of manufacturing a field emission type electron source device according to a fifth aspect includes a step of forming a protruding portion for forming a cathode on a substrate made of a semiconductor or a metal, and the protruding portion. Forming an insulating layer on the surface of the substrate by oxidation, forming a resistive layer on a portion of the insulating layer excluding the tip portion of the protruding portion, and forming a gate electrode layer on the resistive layer A step of exposing the tip portion of the cathode by removing the tip portion of the protruding portion of the insulating layer, and a step of separating the portion of the gate electrode layer surrounding the tip portion of the cathode and the other portion. It is characterized by

A method of manufacturing a field emission type electron source device according to a sixth aspect of the present invention includes a step of forming a protruding portion for forming a cathode on a substrate made of a semiconductor or a metal,
Forming an insulating layer on the surface of the substrate including the protruding portion by oxidation, forming a resistive layer on a portion of the insulating layer excluding the tip portion, and projecting on the resistive layer The step of forming a gate electrode layer in a portion excluding the portion surrounding the tip portion of the formed portion, and the step of removing the tip portion of the protruding portion of the insulating layer to expose the tip portion of the cathode. To do.

[0014]

Since the field emission type electron source device according to the present invention is configured to include the resistance connected in series with the gate electrode, a leak current easily flows between a part of the cathode and the gate electrode. Even so, since the leakage current is limited by the resistance, the electron emitting portion including the cathode and the gate electrode is less likely to be broken.

Further, when the operating voltage of a part of the cathodes of the plurality of electron emitting portions is low, the current flowing through the gate electrode becomes large, and the voltage drop due to the resistance connected in series to the gate electrode is caused. Since the gate voltage is reduced and the operating voltage is suppressed to be low, the electron emitting portion is less likely to be destroyed.

According to another aspect of the field emission electron source device of the present invention, the resistance layer formed on the insulating layer and in the vicinity of the tip of the cathode and the portion of the resistance layer surrounding the tip of the cathode are separated from the cathode. The first gate electrode portion formed to extract electrons and the portion of the resistance layer excluding the first gate electrode portion,
It was configured to include a first gate electrode portion and a second gate electrode portion formed separately. Therefore, the resistance value of the thin film resistance layer connecting the first gate electrode portion forming the individual electron emitting portion and the second gate electrode portion forming the entire gate electrode is R, and a certain electron emitting portion in the array is emitted. If the gate current of the portion is Ig and the voltage applied to the second gate electrode portion is Vg, the voltage V applied to the electron emitting portion is V
Is represented by V = Vg−R × Ig. Therefore, even if the gate current Ig increases in each electron emitting portion, the voltage V applied to the electron emitting portion decreases, and the electron emitting portion is less likely to be destroyed.

According to another aspect of the field emission electron source device of the present invention, a resistance layer formed on the insulating layer and in the vicinity of the tip of the cathode and a portion of the resistance layer excluding the portion surrounding the tip of the cathode. , And a gate electrode formed to extract electrons from the cathode. Therefore, when a leak current flows between the cathode and the gate electrode, the voltage drop in the resistance layer between the gate electrode and the cathode causes the potential of the portion of the resistance layer near the tip of the cathode to pass through the resistance layer. It becomes lower than the potential of the gate electrode depending on the magnitude of the flowing current. As a result, the electric field applied to the cathode is reduced,
The leak current between the cathode and the gate electrode is reduced, and the electron emission portion is less likely to be destroyed.

In the field emission type electron source device according to the fourth aspect of the present invention, the resistance layer is made of a non-photoconductive material. Therefore, the performance deterioration due to light irradiation of the gate current, the current emission capacity and the breakdown voltage is small. Are better.

According to a fifth aspect of the present invention, there is provided a method of manufacturing a field emission type electron source device, wherein a step of forming a resistive layer on a portion of the insulating layer excluding a tip portion of the protruding portion, and a gate electrode layer on the resistive layer And the step of separating the portion surrounding the tip portion of the cathode of the gate electrode layer and the other portion from each other.
A field-emission electron source device that includes a first gate electrode portion that constitutes an individual electron source and a second gate electrode portion that constitutes an entire gate electrode and that does not easily cause the destruction of each electron emission portion is facilitated. It can be manufactured.

According to a sixth aspect of the present invention, there is provided a method of manufacturing a field emission type electron source device, wherein a step of forming a resistive layer on a portion of the insulating layer excluding a tip portion of the projecting portion, and a projecting portion on the resistive layer. And a step of forming a gate electrode layer in a portion excluding the portion surrounding the tip portion of
A resistance layer formed on the insulating layer and in the vicinity of the tip portion of the cathode, and a portion of the resistance layer other than the portion surrounding the tip portion of the cathode, including a gate electrode formed to extract electrons from the cathode, It is possible to easily manufacture the field emission type electron source device in which the electron emitting portion is not easily broken.

[0021]

The first embodiment of the field emission type electron source device of the present invention will be described below.
An example of the above will be described with reference to the drawings.

The field emission type electron source device of this embodiment is shown in FIG.
As shown in FIG. 1, the silicon substrate 11, the cold cathode 10, the insulating layer 12, the resistance layer 13, and the electron emission portion gate electrode 14
a and the common gate electrode 14b.

An embodiment of the method for manufacturing a field emission electron source according to the present invention will be described with reference to FIG.

First, as shown in FIG. 2A, the specific resistance ρ
= 0.01 to 0.02 Ω · cm n-type silicon substrate 11
The surface of is thermally oxidized to form a thermally oxidized silicon layer 15 having a thickness of 0.2 to 0.3 μm. Next, a circular pattern is formed on the surface of the thermal silicon oxide layer 15 by using a resist, and the thermal silicon oxide layer 15 is etched to form a circular thermal silicon oxide mask as shown in FIG. 2B. 15a is formed.

Then, the thermal silicon oxide mask 15 is formed.
2a, the surface of the silicon substrate 11 is isotropically etched by a dry etching method to form a convex portion 11a for forming the cold cathode 10 protruding in a conical shape as shown in FIG. 2C. Formed on the surface of. Although the convex portion 11a has a conical shape in this embodiment, the cold cathode 10
The shape of the convex portion 11a for configuring the above is not limited to this. Further, the surface of the silicon substrate 11 on which the convex portions 11a are formed is thermally oxidized, and as shown in FIG.
A thermal silicon oxide layer 12a having a thickness of about 0.3 to 0.5 μm is grown. At the time of this thermal oxidation, the surface of the convex portion 11a of the silicon substrate 11 is also thermally oxidized at the same time, and the conical cold cathode 10 is formed.

Then, the silicon substrate 11 including the cold cathode 10 is placed in a vacuum vapor deposition apparatus, and as shown in FIG. 2E, while rotating the silicon substrate 11 about the perpendicular 16 of the cold cathode 10, The resistance layer 13 having a thickness of about 0.1 to 0.5 μm is formed from the convex portion 11a by vapor-depositing silicon to be the resistance layer 13 onto the silicon substrate 11 from diagonally above as shown by an arrow A in the figure. It is deposited on the silicon dioxide layer 12a and the silicon dioxide mask 15a formed on the substrate 11 on the skirt side of the tip of the cold cathode 10. Then, as shown in FIG. 2F, while rotating the silicon substrate 11 as in the case of depositing the silicon, molybdenum forming the gate electrode layer 14 is removed from the silicon substrate 11 by an arrow A in the figure. The gate electrode layer 14 having a thickness of about 0.3 μm is vapor-deposited obliquely from above.
It is deposited on the resistance layer 13.

Next, a silicon dioxide mask 15a unnecessary as an electron emission source and a part of the silicon dioxide layer 12a covering the tip of the cold cathode 10 are etched with an etching material composed of a mixed aqueous solution of hydrofluoric acid and ammonium fluoride. Then, as shown in FIG. 2G, the tip of the cold cathode 10 included in the silicon substrate 11 is exposed. Thereby, each of the insulating layer 12, the resistance layer 13, and the gate electrode layer 14 is formed so as to surround the tip portion of the cold cathode 10 and expose the tip portion of the cold cathode 10.
The surface in the vicinity of 0 is formed to have the same height as the height of the tip of the cold cathode 10.

Finally, a resist pattern is formed on the surface of the gate electrode layer 14 by using a resist, and the gate electrode layer 14 is etched to form a pattern as shown in FIG. It is divided into a donut-shaped electron emitting portion gate electrode 14a and a common gate electrode 14b. By the above manufacturing method, the field emission electron source device of the present invention shown in FIGS. 2H and 1 is manufactured.

As shown in FIG. 1, the cold cathode 10 of the present embodiment.
Are formed so as to project in a conical shape on the silicon substrate 11 as the substrate electrode. An insulating layer 12 is formed on the skirt side of the tip of the cold cathode 10 included in the silicon substrate 11. The insulating layer 12 is formed by oxidizing the surface of the silicon substrate 11 forming the substrate electrode. A resistance layer 13 is formed on the insulating layer 12. Further, on the resistance layer 13, a gate electrode layer 14 is laminated as an electric field applying electrode to which a positive voltage is applied to emit electrons from the cold cathode 10. The gate electrode layer 14 includes an electron emission portion gate electrode 14a,
It is separated from the common gate electrode 14b. Further, the electron emitting portion gate electrode 14a is electrically connected to the common gate electrode 14b through the resistance layer 13.

If a current does not flow between the cold cathode 10 and the electron emitting portion gate electrode 14a when a positive voltage is applied to the common gate electrode 14b, the electron emitting portion gate electrode 14a.
Is the common gate electrode 14b after a while.
And the same potential as. However, when a leak current flows between the cold cathode 10 and the electron emission part gate electrode 14 a, a current flows through the resistance layer 13 between the electron emission part gate electrode 14 a and the common gate electrode 14 b, and the resistance layer 13 Due to the voltage drop, the potential of the electron emitting portion gate electrode 14a becomes lower than the potential of the common gate electrode 14b depending on the magnitude of the current flowing through the resistance layer 13. As a result, cold cathode 1
0 and the electron emitting portion gate electrode 14a are reduced in electric field, and the cold cathode 10 and the electron emitting portion gate electrode 1
The leak current between 4a and 4a becomes small.

In this way, the resistance formed by the resistance layer 13 limits the leak current between the cold cathode 10 and the electron-emitting-part gate electrode 14a, so that the electron-emitting part is destroyed by the leak current. Prevent.

The applicant of the present invention has prepared a field emission type electron source device having the resistance layer 13, the electron emission part gate electrode 14a and the common gate electrode 14b formed by the steps shown in FIGS. 2 (A) to (H). J and the resistance layer 13 formed by the process shown in FIGS. 2A to 2H and omitting FIG. 2E and FIG. 2H is not formed,
In addition, the gate electrode layer 14 is the gate electrode 14a of the electron emission portion.
The anode current and the gate current of the field emission type electron source device K of the conventional example which is not separated into the common gate electrode 14b and the common gate electrode 14b were measured.

In both the field emission type electron source devices J and K, the pitch of the electron emitting portions is 20 μm and the number of the electron emitting portions is 1 × 10.
There are ^four . Both the field-emission electron source devices J and K are arranged in a vacuum container and are 1 mm from the field-emission electron source device.
A stainless steel plate-shaped anode was placed at a distant position, and the measurement was performed at a cathode-anode voltage of 200 V and a vacuum degree of 1 × 10 ⁻⁹ Torr. Regarding the field emission type electron source device J, when the voltage between the cathode and the gate electrode is 90 V, the anode current is 2
The current was 1 mA or less and the gate current was 1 µA or less, and the breakdown occurred at a voltage between the cathode and the gate electrode of 100 V, and thereafter, the anode current was 1 µA or less and the gate current was 100 mA or more at the cathode-gate electrode voltage of 10 V. Regarding the field emission electron source device K, when the voltage between the cathode and the gate electrode is 60 V, the anode current is 200 μA and the gate current is 5 μA, and the breakdown occurs at the voltage between the cathode and the gate electrode 70 V, and then between the cathode and the gate electrode. The anode current was 1 μA or less and the gate current was 100 mA or more at a voltage of 10V.

Thus, the device J according to the present invention is
It can be seen that the gate current is smaller than that of the device K of the conventional example, and the current discharge capability and breakdown voltage are excellent.

In this embodiment, the silicon substrate 11 is used as the substrate, but the substrate is not limited to this, and a substrate obtained by coating a semiconductor or metal on another semiconductor, metal or glass substrate. You may use.

Although the silicon dioxide layer 15 formed by thermal oxidation is used as the etching mask for the silicon substrate 11, the material and forming method of the etching mask are not limited to this, and may be changed depending on the type of substrate and the etching method. The material of the etching mask may be used, or it may be formed by diffusion or deposition.

Further, although the silicon substrate 11 was etched by dry etching, it may be etched by wet etching.

Although silicon by oblique rotation vapor deposition was used for the resistance layer 13, the material and forming method of the resistance layer are not limited to this, and other resistors may be used. 13 may be deposited by sputtering.

Further, although molybdenum is used for the gate electrode layer 14, the present invention is not limited to this, and other metals or alloys, conductive oxides or nitrides may be used.

Next, a second embodiment of the field emission type electron source device of the present invention will be described with reference to the drawings.

The field emission type electron source device of this embodiment is shown in FIG.
As shown in FIG. 3, it is composed of a silicon substrate 11, a cold cathode 10, an insulating layer 12, a resistance layer 13, and a gate electrode layer 14.

An embodiment of the method for manufacturing a field emission type electron source of the present invention will be described with reference to FIG.

First, as shown in FIG. 4 (A), the specific resistance ρ
= 0.01 to 0.02 Ω · cm n-type silicon substrate 11
The surface of is thermally oxidized to form a thermally oxidized silicon layer 15 having a thickness of 0.2 to 0.3 μm. Then, for example, a circular pattern is formed on the surface of the thermally oxidized silicon layer 15 using a resist, and the thermally oxidized silicon layer 15 is etched to form a circular thermally oxidized silicon mask 15a as shown in FIG. 4B. Form.

Then, the thermal oxide silicon mask 15 is formed.
The surface of the silicon substrate 11 is isotropically etched by a dry etching method using a, and as shown in FIG. 4C, the convex portion 11a for forming the cold cathode 10 protruding in a conical shape is formed on the silicon substrate. It is formed on the surface of 11. In this embodiment, the protrusion 11a has a conical shape, but the shape of the protrusion 11a for forming the cold cathode 10 is not limited to this. Further, the surface of the silicon substrate 11 on which the convex portions 11a are formed is thermally oxidized, and as shown in FIG.
Thermally oxidized silicon layer 12a having a thickness of about 0.5 μm
Grow. At the time of this thermal oxidation, the surface of the convex portion 11a of the silicon substrate 11 is also thermally oxidized at the same time, and the conical cold cathode 10 is formed.

Then, the silicon substrate 11 including the cold cathode 10 is placed in a vacuum vapor deposition apparatus, and as shown in FIG. 4E, while rotating the silicon substrate 11 about the perpendicular 16 of the cold cathode 10, The resistance layer 13 having a thickness of about 0.1 to 0.5 μm is formed from the convex portion 11a by vapor-depositing silicon to be the resistance layer 13 onto the silicon substrate 11 from diagonally above as shown by an arrow A in the figure. It is deposited on the silicon dioxide layer 12a and the silicon dioxide mask 15a formed on the substrate 11 on the skirt side of the tip of the cold cathode 10. Then, as shown in FIG. 4F, while the silicon substrate 11 is being rotated, molybdenum forming the gate electrode layer 14 is removed from the silicon substrate 11 by the arrow A in the figure as in the case of the silicon vapor deposition. Is vapor-deposited obliquely from above to deposit a gate electrode layer 14 having a thickness of about 0.3 μm. However, during the vapor deposition of molybdenum,
The angle between the vertical line 16 and the axis of rotation is made smaller than that of the step shown in FIG. 4E, and the silicon dioxide layer 12a formed on the substrate 11 further on the skirt side than the tip of the cold cathode 10 is formed. Deposit on the resistive layer overlying the silicon dioxide mask 15a.

Finally, the silicon dioxide mask 15a, which is unnecessary as an electron emission source, and a part of the silicon dioxide layer 12a covering the tip of the cold cathode 10 are made of an etching material composed of a mixed aqueous solution of hydrofluoric acid and ammonium fluoride. By removing the silicon substrate 11 as shown in FIG.
The tip of the cold cathode 10 included in is exposed. As a result, the insulating layer 12, the resistance layer 13, and the gate electrode layer 14 are formed so as to surround the tip portion of the cold cathode 10 and expose the tip portion of the cold cathode 10.
The surface in the vicinity of 0 is formed to have the same height as the height of the tip of the cold cathode 10.

By the above manufacturing method, the field emission type electron source device of the present invention shown in FIGS. 4G and 3 is manufactured.

As shown in FIG. 3, the cold cathode 10 of this embodiment is
Are formed so as to project in a conical shape on the silicon substrate 11 as the substrate electrode. An insulating layer 12 is formed on the skirt side of the tip of the cold cathode 10 included in the silicon substrate 11. The insulating layer 12 is formed by oxidizing the surface of the silicon substrate 11 forming the substrate electrode. A resistance layer 13 is formed on the insulating layer 12. Further, on the resistance layer 13, a gate electrode layer 14 as an electric field applying electrode to which a positive voltage is applied in order to emit electrons from the cold cathode 10 is provided at a tip portion of the cold cathode 10 further than the resistance layer 13. Stacked on the skirt side.

If a current does not flow between the cold cathode 10 and the gate electrode 14 when a positive voltage is applied to the gate electrode 14, the portion of the resistance layer 13 close to the tip of the cold cathode 10 will be left for a while. After that, the potential becomes the same as that of the gate electrode 14. However, when a leak current flows between the cold cathode 10 and the gate electrode 14, the gate electrode 14 and the cold cathode 1
Due to the voltage drop across the resistance layer 13 between 0 and
The potential of the portion close to the tip of the cold cathode 10 becomes lower than the potential of the electrode 14 depending on the magnitude of the current flowing through the resistance layer 13. As a result, the electric field applied to the cold cathode 10 becomes small, and the leak current between the cold cathode 10 and the gate electrode 14 becomes small.

In this way, the resistance formed by the resistance layer 13 limits the leak current between the cold cathode 10 and the gate electrode 14, so that the electron emission portion is prevented from being destroyed by the leak current. .

The applicant of the present invention has made the resistance layer 13 and the gate electrode 1 produced by the steps shown in FIGS.
For the field emission type electron source device L in which No. 4 was formed, the anode current and the gate current were measured. In the field emission electron source device L, the pitch of the electron emitting portions is 20 μm and the number of electron emitting portions is 1 × 10 ⁴ . The field-emission electron source device L is arranged in a vacuum container and is 1 mm from the field-emission electron source device.
A stainless steel plate-shaped anode was placed at a distant position, and the measurement was performed at a cathode-anode voltage of 200 V and a vacuum degree of 1 × 10 ⁻⁹ Torr.

Regarding the field emission type electron source device L, when the voltage between the cathode and the gate electrode is 95 V, the anode current is 2 mA and the gate current is 1 μA or less, and the cathode-gate electrode voltage is 1
Destruction occurred at 10 V, and thereafter, at a cathode-gate electrode voltage of 10 V, an anode current was 1 μA or less and a gate current was 100 m.
It was A or higher.

As described above, the device L according to the present embodiment has a smaller gate current than the device K according to the conventional example, and
It can be seen that the current discharge capability and breakdown voltage are also excellent.

Although the silicon substrate 11 is used as the substrate in the above embodiment, the substrate is not limited to this, and a substrate such as another semiconductor or metal or glass substrate coated with the semiconductor or metal may be used. You may use.

Although the silicon dioxide layer 15 formed by thermal oxidation is used as the etching mask for the silicon substrate 11, the material and forming method of the etching mask are not limited to this, and may be changed depending on the type of substrate and the etching method. The material of the etching mask may be used, or it may be formed by diffusion or deposition.

Further, although the silicon substrate 11 was etched by dry etching, it may be etched by wet etching.

Although silicon is used for the resistance layer 13 by oblique rotation vapor deposition, the material and forming method of the resistance layer are not limited to this, and other resistance bodies may be used. 13 may be deposited by sputtering.

Although molybdenum is used for the gate electrode layer 14, the present invention is not limited to this, and other metals or alloys, conductive oxides or nitrides may be used.

Next, a third embodiment of the field emission type electron source device of the present invention will be described with reference to the drawings.

In the field emission type electron source device of the present embodiment, silicon germanium is used as the material of the resistance layer 13 formed by the process shown in FIG. 2E in the above-mentioned first embodiment, and deposited by sputtering. A field emission type electron source device M was manufactured by the same method except that

The field emission type electron source device M has an electron emitting portion pitch of 20 μm and the number of electron emitting portions × 10 ⁴ .
The field-emission electron source device M is arranged in a vacuum container, and a stainless steel plate-shaped anode is arranged at a position 1 mm away from the field-emission electron source device.
The measurement was performed at V and a vacuum degree of 1 × 10 ⁻⁹ Torr. Regarding the field emission type electron source device M, when the irradiation light intensity to the field emission type electron source device M is 1 nW / cm ² or less, the cathode-
When the voltage between the gate electrodes is 90 V, the anode current is 2 mA, the gate current is 1 μA or less, and the cathode-gate electrode voltage is 10
Destruction occurs at 0 V, and then, at a cathode-gate electrode voltage of 10 V, an anode current is 1 μA or less and a gate current is 100 mA.
That was all.

Further, the wavelength 6 for the field emission type electron source device M is
Irradiation light intensity of 32.8 nm laser light 1 mW / cm
² , the cathode-gate electrode voltage is 90 V, the anode current is 2 mA, and the gate current is 1 μA or less, and breakdown occurs at the cathode-gate electrode voltage of 100 V, and then the anode is at the cathode-gate electrode voltage of 10 V. The current was 1 μA or less and the gate current was 100 mA or more.

With respect to the field emission type electron source device J described in the first embodiment, the irradiation light intensity of the laser beam having the wavelength of 632.8 nm to the field emission type electron source device J is 1 m.
At W / cm ² , when the voltage between the cathode and the gate electrode is 70 V, the anode current is 250 μA and the gate current is 1 μA or less, and the breakdown occurs at the cathode-gate electrode voltage of 85 V, and then the cathode-gate electrode voltage is 10 V. And anode current 1μ
It was A or less and the gate current was 100 mA or more.

As described above, the field-emission electron source device M according to the third embodiment has a gate current, a current-emission capability, and a breakdown voltage by light irradiation that are higher than those of the conventional field-emission electron source device J. It can be seen that the performance is small and excellent.

In the above-mentioned embodiment, the silicon germanium by sputtering is used for the resistance layer 13, but the material and the forming method of the resistance layer are not limited to this, and other resistors may be used. Alternatively, the resistance layer 13 may be deposited by vapor deposition.

[0066]

According to the field emission type electron source device of the first aspect of the present invention, in some of the electron emitting portions, a leak current is generated on the surface of the insulating layer due to contamination in the fabrication process, or the fabrication process is performed. There are many components in which electrons emitted from the cold cathode are incident on the gate electrode due to variation in shape caused by non-uniformity of the mouth, and even if a leak current easily flows between some cathodes and the gate electrode, The leakage current is limited by the resistance connected in series with the gate electrode, so that the electron emitting portion including the cathode and the gate electrode is less likely to be destroyed.

Further, when the operating voltage of a part of the cathodes of the plurality of electron emitting portions is low, the current flowing through the gate electrode becomes large, and the voltage drop due to the resistance connected in series to the gate electrode is caused. Since the gate voltage is reduced and the operating voltage is suppressed to be low, the electron emitting portion is less likely to be destroyed.

Therefore, a highly reliable field emission type electron source device can be obtained.

Further, as compared with the structure in which the resistance is connected in series to the cathode and the anode, the resistance is connected in series to the gate electrode having a small current, so that the power consumption in the resistance can be reduced, and It is also possible to suppress heat generation due to the power consumed by the resistance.

According to the field emission type electron source device of the second aspect, the first gate electrode portion forming each electron emitting portion and the second gate electrode portion forming the entire gate electrode are connected. If the resistance value of the thin film resistance layer is R, the gate current of a certain electron emitting portion in the array is Ig, and the voltage applied to the second gate electrode is Vg, the voltage V applied to the electron emitting portion is It is represented by V = Vg−R × Ig. Therefore, even if the gate current Ig increases in each electron emitting portion, the voltage V applied to the electron emitting portion decreases, and the electron emitting portion is less likely to be destroyed.

According to the field emission type electron source device of the third aspect, when a leak current flows between the cathode and the gate electrode, the resistance drops due to the voltage drop in the resistance layer between the gate electrode and the cathode. The potential of the portion of the layer near the tip of the cathode is
The potential becomes lower than the potential of the gate electrode depending on the magnitude of the current flowing through the resistance layer. As a result, the electric field applied to the cathode is reduced, the leak current between the cathode and the gate electrode is reduced, and the electron emission portion is less likely to be destroyed.

According to the field emission type electron source device of the fourth aspect, since the resistance layer is made of the non-photoconductive material, the performance deterioration due to the light irradiation of the gate current, the current emission capability and the breakdown voltage. Is small and excellent.

According to the manufacturing method of the field emission type electron source device of the fifth aspect, the first gate electrode portion which is formed on the resistance layer and constitutes each electron source and the entire gate electrode are constituted. It is possible to easily manufacture a field emission type electron source device including the second gate electrode portion, in which destruction of individual electron emitting portions is less likely to occur and at a high yield.

According to the method of manufacturing the field emission type electron source device of the sixth aspect, the resistance layer formed on the insulating layer and in the vicinity of the tip portion of the cathode and the tip portion of the cathode on the resistance layer are surrounded. A field-emission electron source device including a gate electrode formed to extract electrons from the cathode in the part excluding the part can be easily manufactured with high yield, and the electron-emitting part is less likely to be broken.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a field emission type electron source device according to the present invention.

FIG. 2 is a cross-sectional view showing a method for manufacturing a field emission electron source device according to the present invention.

FIG. 3 is a perspective view showing an embodiment of a field emission type electron source device according to the present invention.

FIG. 4 is a cross-sectional view showing a method of manufacturing a field emission electron source device according to the present invention.

[Explanation of symbols]

 10 Cold cathode 11 Silicon substrate 12 Insulating layer 13 Resistive layer 14 Gate electrode layer 14a Electron emission part gate electrode 14b Common gate electrode 15 Silicon dioxide layer 15a Silicon dioxide mask

Claims (6)

[Claims] 1. A cathode comprising a protruding portion on a substrate,
A gate electrode provided near the protruding tip portion of the cathode for extracting electrons from the cathode,
A field emission electron source device that emits electrons in a high electric field, further comprising a resistor connected in series with the gate electrode. 2. A field emission type electron source device which emits electrons in a high electric field, comprising a cathode for emitting electrons, which is composed of a protruding portion on a substrate made of a semiconductor or a metal, and the cathode on the substrate. An insulating layer formed excluding the protruding tip portion of the cathode, a resistance layer formed on the insulating layer and in the vicinity of the tip portion of the cathode, and a portion surrounding the tip portion of the cathode on the resistance layer. A first gate electrode portion formed to extract electrons from the cathode, and a portion of the resistance layer excluding the first gate electrode portion, which is formed separately from the first gate electrode portion. The second done
Field emission type electron source device including a gate electrode part of the. 3. A field emission type electron source device for emitting electrons in a high electric field, comprising a cathode for emitting electrons, which is composed of a protruding portion on a substrate made of a semiconductor or a metal, and the cathode on the substrate. An insulating layer formed excluding the protruding tip portion of the cathode, a resistance layer formed on the insulating layer and in the vicinity of the tip portion of the cathode, and a portion surrounding the tip portion of the cathode on the resistance layer. A field emission electron source device including a gate electrode formed to extract electrons from the cathode, in a portion other than the portion. 4. The field emission electron source device according to claim 2, wherein the resistance layer is made of a non-photoconductive material. 5. A method of manufacturing a field emission type electron source device which emits electrons in a high electric field, comprising the step of forming a protruding portion to form a cathode on a substrate made of a semiconductor or a metal. Forming an insulating layer on the surface of the substrate including the protruding portion by oxidation, forming a resistive layer on a portion of the insulating layer excluding a tip portion of the protruding portion, A step of forming a gate electrode layer on the resistance layer; a step of removing a tip portion of the protruding portion of the insulating layer to expose a tip portion of a cathode; and a step of exposing the tip portion of the cathode of the gate electrode layer. A method of manufacturing a field emission type electron source device, comprising the step of separating the surrounding portion and the other portion. 6. A method of manufacturing a field emission type electron source device which emits electrons in a high electric field, comprising the step of forming a protruding portion to form a cathode on a substrate made of a semiconductor or a metal, and Forming an insulating layer on the surface of the substrate including a protruding portion by oxidation; forming a resistive layer on a portion of the insulating layer excluding a tip portion of the protruding portion; Forming a gate electrode layer on a portion of the layer other than the portion surrounding the tip portion of the protruding portion; and removing the tip portion of the protruding portion of the insulating layer to expose the tip portion of the cathode. A method for manufacturing a field emission type electron source device including: