JPH07134952A - Built-in element of electron tube and manufacture of element thereof - Google Patents

Abstract

PURPOSE:To suppress discharge due to secondary electrons and improve manufacturing efficiency and prevent the convergence of an electric field by covering an exposed face of an insulating substrate and a metal terminal with a metal oxide coating having a small secondary electron emitting ratio. CONSTITUTION:A resistor layer 12 is formed as an electric circuit part on an insulating substrate 11. A conductor layer 13 electrically integrated with the resistor layer 12 is formed for joining and a plate-like metal terminal 16 is so caulked to the substrate 11 as to be connected electrically to the conductive layer 13. An insulation coating layer 14 is also formed on both sides of the substrate 11, so that the resistor layer 12 is covered. Further, a metal oxide coating 18 consisting of, for example, a mixture of silica methoxide and aluminum isopropoxide is so formed as to cover ceramic exposed faces of the side faces of the substrate 11 and the insulation coating layer 14. The coating 18 is formed uniformly at once on the whole part of a resistor element by sol-gel reaction and dehydration and condensation reaction of organometallic compounds without leaving any uncoated parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron tube built-in element suitable for use in, for example, a color cathode ray tube and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, an electron tube, for example, a color cathode ray tube used in a color television receiver is shown in FIGS.
2 shows the whole, and FIG. 3 shows the vicinity of the electron gun. That is, the fluorescent surface 22 is formed on the inner surface of the panel of the glass vacuum envelope 21. On the other hand, an electron gun 24 which emits an electron beam is arranged inside the neck 23, and the electron beam is deflected and scanned by a deflection yoke 28 attached to the cone portion to obtain a fluorescent screen 22. The desired image is displayed on. The electron gun 24 includes a cathode that generates an electron beam, an electrode that applies a low voltage to suppress the generation of the electron beam from the cathode, and an electrode that focuses and accelerates the electron beam emitted from the cathode. A plurality of electrodes composed of
Are arranged at predetermined intervals in the direction.

Generally, an electrode for accelerating an electron beam is
A high-voltage anode voltage is applied from a high-voltage supply button (anode button) 25 provided in the cone portion of the vacuum envelope 21 through the internal conductive film 26. Particularly in a color cathode ray tube, a high voltage of about 20 to 35 KV is applied. Furthermore,
As is clear from FIG. 3, the electron gun 24 in the neck 23 is provided with a built-in element such as a resistance element 29, which is a voltage dividing element. In some electron guns 24, it is necessary to supply a high voltage to the convergence electrode, the focus electrode, etc. in addition to the anode voltage in order to improve the focusing degree of the electron beam. In such cases,
When a high voltage is supplied from the stem portion 27 of the color cathode ray tube, a problem occurs in terms of withstand voltage. Therefore, the anode voltage is divided by the resistance element 29, and the convergence electrode and the convergence electrode are divided.
A predetermined high voltage is supplied to the dust electrode and the like.

A resistance element 29 built in such a color cathode ray tube has been conventionally used, for example, as shown in FIGS.
FIG. 2B is a plan view showing a state of being configured as shown in FIG. 3C, in which FIG. 3A is seen through from the insulating coating layer forming the outer surface portion.
6A is a cross-sectional view taken along line BB ′ of FIG. 7A and seen in the direction of the arrow, and FIG. 7C is a cross-sectional view showing an enlarged main part of FIG.

That is, on a ceramic insulating substrate 31 whose main component is aluminum oxide, a resistor made of lead ruthenate oxide having a predetermined sheet resistance and lead borosilicate glass is used. A resistance layer 33 is formed by printing the material in a zigzag pattern, drying and firing, and a bonding conductor layer 32 electrically integrated with the resistance layer 33 and an insulating substrate 31 so as to be bonded to the bonding conductor layer 32. And a metal terminal 36 crimped thereto. Further, the resistance layer 33
An insulating coating layer 34 is formed so as to cover the insulating substrate 31.
Insulation-coated glass 35
Are formed. In the manufacturing process of such a resistance element 29, a plurality of sets up to the step of forming the insulating coating layer 34 are carried out on a single insulating substrate having a plurality of dividing grooves, and then a plurality of sets are formed along the dividing grooves. It is divided into resistance elements 29. Therefore, after the division, the ceramic portion is exposed on the side surface of the insulating substrate 31. In addition, when the metal terminals 36 are joined by caulking, the ceramic portion is exposed around the through-hole portion 37 on the back surface of the insulating substrate 31 in order to prevent the glass from chipping. Furthermore, the crimped metal terminal 36
Are exposed on the back surface side of the insulating substrate 31.

Generally, when the resistance element 29 is built in a color cathode ray tube, the back surface side of the resistance element 29 faces the inner wall of the neck. Therefore, the electrons generated from the cathode and deviating from the regular orbit collide with the resistance element 29, and at that time, secondary electrons are emitted from the resistance element 29. At this time, in a glass-based material having a small secondary electron emission ratio, the amount of secondary electron emission is small, which is not a big problem. However, in the exposed portion of the ceramic having a large secondary electron emission ratio, the amount of secondary electron emission is large and discharge is induced. As a result, unnecessary discharge is continuously generated between the inner wall of the neck of the color cathode ray tube and the resistance element 29. Further, when the metal terminal 36 is exposed, a discharge from the high voltage electrode portion of the electron gun 24 is sporadically generated there.

When a continuous or single discharge is generated in this way, the potential at each part becomes unstable, making it difficult to supply a predetermined voltage to the electrodes of the electron gun, and a color cathode ray tube. As a result, it becomes difficult to provide high-quality images.

Therefore, the side surface of the insulating substrate 31, the exposed ceramics portion around the through-hole portion 37 and the metal terminal 3 are provided.
The back surface caulked portion 36a of No. 6 is coated with the insulating coated glass 35 having a small secondary electron emission ratio, and the continuous discharge due to the secondary electron emission ratio from the ceramic exposed portion of the insulating substrate 31 and the caulked portion 36a are coated. It is insulated to prevent a single discharge from the high voltage electrode part of the electron gun.

The insulating coating glass 35 is an insulating coating layer 34.
It is made of the same lead borosilicate glass material. This is because by using the same material, the dielectric constants are made the same and nonuniformity of the electric field distribution is prevented. The insulating coated glass 35 is coated with a dispenser by further diluting a pasty glass material with a solvent to form a liquid. In addition, in FIG. 4C, the insulating coated glass 35 is not shown.

[0010]

As described above, in the conventional resistance element 29, the insulating substrate 31 and the metal terminal 3 are used.
When the exposed portion of 6 is coated with the insulating coated glass 35, the work is complicated due to the application by the dispenser, and the application time per one resistance element 29 is long and the productivity is low. In addition, uneven coating and unpainted portions frequently occur, so that an inspection / correction process is required to correct them, and there is a problem in productivity, and means for solving these problems have been desired.

The present invention has been made in view of the above circumstances, and has a built-in high-quality electron tube capable of suppressing discharge due to secondary electrons, further improving manufacturing efficiency, and preventing electric field concentration. An object is to provide an element and a manufacturing method thereof.

[0012]

According to the present invention, an electric circuit portion is formed on an insulating substrate, an insulating coating layer is formed so as to cover the electric circuit portion, and the electric circuit portion is directly or via a bonding conductor layer. In a built-in element of an electron tube in which metal terminals are electrically connected to each other, a metal oxide film is attached so as to cover the exposed surface of the insulating substrate, the insulating coating layer, and the metal terminal. The thickness of the metal oxide film is set in the range of 100 to 5000 angstrom.

Further, according to the present invention, an electric circuit portion is formed on an insulating substrate, an insulating coating layer is formed so as to cover the electric circuit portion, and a metal terminal is directly or electrically connected to the electric circuit portion via a bonding conductor layer. In a method of manufacturing a built-in element of an electron tube for electrically connecting the above, the whole built-in element is immersed in an organometallic compound solution, and then heat treated to cover the exposed surface of the insulating substrate, the insulating coating layer, and the metal terminal. It is a method of manufacturing a built-in element of an electron tube for forming an oxide film. Then, even when performing a plurality of sets up to the step of forming the insulating coating layer on a single insulating substrate having a plurality of dividing grooves, and then dividing into a plurality of sets of elements along the dividing grooves, Similarly, a metal oxide film is formed on each of the elements.

[0014]

According to the present invention, the entire built-in element is dipped in the organic metal compound solution, the coating film is hydrolyzed by moisture in the air, and further heated to cause dehydration / condensation reaction. A dense metal oxide film is deposited on the entire device. Therefore, discharge due to secondary electrons can be suppressed. Further, defects such as coating unevenness and uncoated portions are reduced, so that manufacturing efficiency can be improved. In this way, it is possible to prevent the concentration of an electric field with a uniform dielectric constant and to obtain a high quality built-in electron tube element.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. A built-in element such as a resistance element of the electron tube according to the present invention is configured as shown in FIGS. 1A, 1B and 1C, and FIG. 1A is seen through from the metal oxide film forming the outer surface portion. A plan view showing the state, (b) is A-
FIG. 3C is a cross-sectional view taken along the line A ′ and viewed in the direction of the arrow, and FIG. 6C is a cross-sectional view showing an enlarged main part of FIG.

That is, a resistance layer 12 which is an electric circuit portion is formed on an insulating substrate 11 made of ceramics containing aluminum oxide as a main component. Specifically, the predetermined sea
The resistance layer 12 is formed by printing, drying, and firing a resistance material composed of lead oxide ruthenate and a lead borosilicate glass having a high resistance value in a zigzag pattern.
Furthermore, the conductor layer 1 for joining electrically integrated with the resistance layer 12
3 is formed, and the plate-shaped metal terminal 16 is crimped to the insulating substrate 11 so as to be electrically connected to the joining conductor layer 13. Reference numeral 17 in the drawing is a through hole portion, and 16
Reference numeral a is a crimped portion of the metal terminal 16. Further, an insulating coating layer 14 is formed on the front and back surfaces of the insulating substrate 11 so as to cover the resistance layer 12.
Are formed. In this embodiment, the insulating coated glass is not formed on the exposed ceramic surface of the side surface of the insulating substrate 11 as in the prior art. In this case, the bonding conductor layer 13 is composed of a mixed sintered layer containing, for example, a nickel-aluminum alloy, a glassy metal oxide, and titanium hydride. The metal terminal 16 is made of nickel.

Further, for example, methoxide silica {Si (OCH ₃ ) _n } and isopropoxide aluminum {Al (O.multidot.O.multidot.n) so as to cover the metal terminals 16, the exposed ceramics surface of the insulating substrate 11 and the insulating coating layer 14. i-C ₃ H
₇ ) _n } is attached to the metal oxide film 18, which is a feature of the present invention. The metal oxide film 18 is uniformly and simultaneously formed on the entire resistance element at once by the sol-gel reaction and the dehydration / condensation reaction of the organometallic compound.
Moreover, it is formed so that there are no defects such as unpainted portions (details will be described later), and it is of high quality and inexpensive. The thickness of the metal oxide film 18 is set in the range of 100 to 5000 angstroms, and is about 1000 angstroms in this embodiment.

Examples of the organometallic compound include Si, Ti, Mg, Sr, Al, and B in the portion of M in the following formula.
methoxide containing a metal such as a {M (OCH ₃ ) _n }, ethoxide {M (OC ₂ H ₅ ) _n }, n-propoxide {M (O · n-C ₃ H ₇ ) _n }, isopropoxide {M
_{(O · i-C 3 H} 7) n} is used at least one of. Next, a method of manufacturing the above resistance element will be described. First, a resistance pattern is printed by a screen printing method using a resistance paste on one surface of an insulating substrate 11 made of ceramics containing aluminum oxide as a main component.
Then, the solvent in the paste is removed by drying at 120 to 150 ° C. for 10 to 20 minutes to form the resistance layer 12. At this time, the resistance paste is a resistance material composed of a metal oxide containing lead ruthenate and lead borosilicate glass, and has a sheet resistance value of about 10 ⁶ to 10 ⁷ Ω / □. Further, the print pattern is a predetermined zigzag pattern so that a predetermined voltage division ratio can be obtained at each metal terminal 16.

Next, a bonding conductor layer 13 made of a conductor paste is printed on the same surface as the resistance layer 12 on the insulating substrate 11. Then, the solvent in the paste is removed by drying at 120 to 150 ° C. for 10 to 20 minutes to form a plurality of bonding conductor layers 13. The sheet resistance for that is 10 ⁴ Ω /
□ Have the following:

Then, the resistance layer 12 and the bonding conductor layer 13 are fired by heating at 840 to 860 ° C. in an air atmosphere for about 8 to 10 minutes. The resistance layer 12 thus obtained has a total resistance value of 2 × 10 ^{9 to} 3 × 10 ⁹ Ω. At this time, when the voltage division ratio at each metal terminal 16 is not within the predetermined range, the resistance layer for resistance value correction provided in each resistance portion of the resistance layer 12 is ground by a sandblast method or the like,
It is corrected so that each partial pressure ratio is within a predetermined range.

Next, a glass paste for insulation coating is printed on predetermined portions of both surfaces of the insulating substrate 11. Then 1
The solvent in the paste is removed by drying at 20 to 150 ° C. for 10 to 20 minutes to form the insulating coating layer 14. At this time, the glass paste is a paste containing lead borosilicate glass as a main component and a mixed material of a transition metal oxide such as iron oxide, chromium oxide and nickel oxide and an organic vehicle. Further, the insulating coating layer 14 is printed so as to have a predetermined film thickness in order to obtain a predetermined withstand voltage characteristic. The film thickness after firing is 200 to 500 μm on the front surface side having the resistance layer 12, and 50 to 200 μm on the other back surface side.

Next, the insulating coating layer 14 is baked by heating at 590 to 620 ° C. in an air atmosphere for about 8 to 10 minutes. Usually, a plurality of sets of the steps up to this point are carried out on a single insulating substrate having a plurality of dividing grooves, and then a plurality of elements are divided along the dividing grooves.

Next, the metal terminals 16 are fixed to the divided conductor layers 13 of the respective elements and the through-hole portions 17 of the insulating substrate 11 by caulking. Then, each of the resistive elements was placed in a metalorganic compound solution in which methoxide silica {Si (OCH ₃ ) _n } and isopropoxide aluminum {Al (O.i-C ₃ H ₇ ) _n } were mixed at a ratio of 1: 3. Soak. At this time, the viscosity of the solution is 10 to 100 poise, and the pulling rate is 100 mm / sec or less.

Then, it is left to stand in the air for 10 to 15 minutes. As a result, the coating film undergoes a hydrolysis reaction due to the moisture contained in the air. This hydrolysis reaction causes sol-
It is gelled to form a porous metal oxide film.

Next, by heating at 450 to 550 ° C. in an air atmosphere for about 10 to 30 minutes, a dehydration / condensation reaction occurs, and the porous metal oxide film is transformed into a non-porous metal oxide film, and the metal oxide is oxidized. The physical film 18 is formed. The thickness of the metal oxide film 18 is about 1000 angstroms.
However, in general, this metal oxide film 18
The thickness may be in the range of 100 to 5000 angstroms. If the metal terminal 16 and the connection lead to the electron gun electrode are connected by laser welding, the metal oxide film 18 is formed.
Does not hinder welding.

After that, the manufacturing process of the conventional resistance element is the same. The resistance element manufactured as described above has a high resistance division ratio of ± 0.7%, and is subjected to a high load test by applying a voltage that is 3 to 4 times the actual use condition for 50 hours. However, the resistance value and the change in the division ratio were within ± 0.2%, which was a very good result. In addition, no discharge or the like induced by secondary electron emission was observed even after the actual operation test for 10,000 hours.

As a result, the coating process for each resistance layer, which is conventionally required, is long, complicated, and lacking in productivity becomes unnecessary. Further, defects such as coating unevenness and unpainted portions are reduced, so that an inspection / correction process for correcting them is unnecessary. Further, since a uniform film can be formed on the entire surface of the resistance layer, the dielectric constant can be made uniform, the concentration of the electric field can be prevented, and the discharge due to the concentration of the electric field can be suppressed.

The organometallic compound is not limited to the above, and for example, Si, Ti, M may be added to the portion of M in the following formula.
Methoxides containing metals such as g, Sr, Al, Ba {M
(OCH ₃ ) _n }, ethoxide {M (OC ₂ H ₅ ).
_n}, n-propoxide {M (O · n-C 3 H 7)
_n}, isopropoxide {M (O · i-C 3 H 7) n}
It suffices to use at least one of the above.

In the above embodiment, the resistance layer is used as an example of the electric circuit section, but the electric circuit section is not limited to a resistor.
The present invention can be applied to a case of using a capacitor, or a combination of a resistor and a capacitor or another semiconductor.

Further, in the above embodiment, the conductor layer 13 for joining is interposed between the resistance layer 12 and the metal terminal 16, but the resistance layer 12 and the metal terminal 16 are electrically connected directly. May be.

[0031]

According to the present invention, the exposed surface of the insulating substrate and the metal terminal are covered with the metal oxide film having a small secondary electron emission ratio. Therefore, it is possible to suppress discharge due to secondary electrons. Further, defects such as coating unevenness and uncoated portions are reduced, so that manufacturing efficiency can be improved. In this way, it is possible to prevent the concentration of an electric field with a uniform dielectric constant and to obtain a high quality built-in electron tube element.

[Brief description of drawings]

1 (a), (b) and (c) show a built-in element of an electron tube according to an embodiment of the present invention, and (a) shows a state seen through from an insulating coating layer forming an outer surface portion. Plan view,
(B) is a cross-sectional view taken along the line AA 'of (a) and viewed in the direction of the arrow, and (c) is a cross-sectional view showing an enlarged main part of (b).

FIG. 2 is a schematic cross-sectional view showing the whole of a general color CRT.

FIG. 3 is an enlarged cross-sectional view showing a main part (near the electron gun structure) of the color cathode ray tube in FIG.

4 (a), (b), (c) show a built-in element of a conventional electron tube, (a) is a plan view showing a state seen through from an insulating coating layer forming an outer surface portion, (b). Is B- in (a)
Sectional drawing which cut | disconnected along the B'line and was seen in the arrow direction, (c) is sectional drawing which expands and shows the principal part of (b).

[Explanation of symbols]

11 ... Insulating substrate, 12 ... Resistance layer (electrical circuit part), 13 ...
Bonding conductor layer, 14 ... Insulating coating layer, 16 ... Metal terminal, 1
8 ... Metal oxide coating.

Claims (4)

[Claims] 1. An electric circuit section is formed on an insulating substrate, an insulating coating layer is formed so as to cover the electric circuit section, and a metal terminal is electrically connected to the electric circuit section directly or through a bonding conductor layer. In a built-in element of an electron tube, which is electrically connected, a metal oxide film is attached so as to cover the exposed surface of the insulating substrate, the insulating coating layer, and the metal terminal. . 2. The electron tube built-in element according to claim 1, wherein the thickness of the metal oxide film is set in a range of 100 to 5000 angstroms. 3. An electric circuit section is formed on an insulating substrate, an insulating coating layer is formed so as to cover the electric circuit section, and a metal terminal is electrically connected to the electric circuit section directly or through a bonding conductor layer. In the method for manufacturing a built-in element of an electron tube connected to, the whole built-in element is immersed in an organometallic compound solution, and then heat-treated to cover the exposed surface of the insulating substrate, the insulating coating layer, and the metal terminal. A method for manufacturing a device with a built-in electron tube, comprising forming a metal oxide film. 4. A plurality of sets up to the step of forming the insulating coating layer are carried out on a single insulating substrate having a plurality of dividing grooves,
Then, divided into a plurality of elements along the dividing groove,
The method for manufacturing an element with a built-in electron tube according to claim 3, wherein the metal oxide film is formed on each element.