TWI533544B - Surge absorber and manufacturing method thereof - Google Patents

Description

Surge absorber and manufacturing method thereof

The present invention relates to surge absorbers for protecting electronic devices from high voltage ingress, such as lightning strikes, and methods of making same.

In general, high voltage, high current pulses are commonly referred to as surges, which are an electronic noise. Such surges are caused by natural lightning strikes, power systems (such as high-voltage circuit breakers (breakers, disconnectors), and large industrial equipment (inductive load switching, arcs and switches, relays, welding machines, etc.). Switching surges, as well as driving surges caused by lifts, motors, etc.).

Nowadays, with the development of semiconductor technology, electronic devices are placed inside in a very large form factor (VLSI). Surge is often transmitted to an electronic device through a power supply, communication, and signal line, thereby damaging the circuitry or semiconductor device disposed in the electronic device. Therefore, in order to protect electronic devices from surge damage, surge absorbers are widely used in military, industrial, and handheld electronic devices.

A typical surge absorber includes a surge absorbing element disposed within the vessel tube and in an insulated state. The surge absorbing element includes a non-conductive element, a conductive plating film surrounding the non-conductive element, and a discharge gap separating the conductive plating film into a plurality of layers, whereby the conductive plating film can be used as a discharge electrode.

As described above, the conductive plating film is used as a discharge electrode and is made of a highly conductive metal such as titanium (Ti) or nickel (Ni). The conductive coating is deposited on the surface of the non-conductive element by a general sputtering method.

However, a conventional surge absorber fabricated by depositing a conductive plating film on a non-conductive member using a sputtering method has a disadvantage in that heat treatment is required because of the bonding of the deposited conductive coating film. The force is weaker.

When heat treatment is performed to increase the bonding force of the conductive plating film deposited on the non-conductive member, the resistance value of the conductive plating film is increased, thereby reducing the reaction time of the surge absorber.

In addition, the thickness of the conductive coating of the conventional surge absorber is proportional to the resistance value. However, for a surge absorber using a high voltage, it is necessary to make the thickness of the conductive coating proportional to the high resistance value, and the surge absorber of the high voltage can only increase the thickness of the conductive coating. To the established value (or above). Therefore, when a surge comes, the conductive coating will suffer severe damage and degrade the characteristics of the surge absorber.

Further, a conventional surge absorber manufactured by depositing a conductive plating film on a non-conductive member by a sputtering method may have a non-uniform thickness of the conductive plating film.

In the case where the conductive coating is not uniform, the comparison result of the discharge starting voltage measured by the surge is applied a plurality of times when the surge simulation is performed, and the discharge is started every time the surge is applied. It is difficult for the voltage to fall within the established range.

The present invention relates to a surge absorber capable of avoiding an increase in resistance value caused by depositing a conductive plating film on an outer surface of a non-conductive member, and avoiding a decrease in reaction time due to an increase in resistance value.

The present invention relates to a surge absorber capable of avoiding a decrease in performance due to the inability to deposit a conductive plating film to a predetermined thickness or more on the outer surface of a non-conductive member.

The present invention relates to a surge absorber in which a conductive plating film of a fixed thickness can be deposited on the outer surface of a non-conductive member.

Embodiments of the present invention provide a method of fabricating a surge absorber comprising: preparing a non-conductive element; depositing a conductive coating on an outer surface of the non-conductive element using chemical vapor deposition, chemical vapor deposition The method rotates the non-conductive element and sprays the deposition solution in a high temperature environment; in the conductive plating film, at least one discharge gap is formed to constitute a surge absorbing element; in the container tube, a surge absorbing element is deposited, and In the container tube, a sealing electrode is sealed at both ends of the container tube, the container tube has an inert gas filled therein; and the lead wire is electrically connected to the individual sealing electrode.

The conductive plating film includes antimony tin oxide containing 0.5% to 5% by weight of tin oxide.

The deposition step of the conductive coating is performed at 600 degrees Celsius or higher and higher than the temperature used for the sealing step.

Another embodiment of the present invention provides a surge absorber comprising: a container tube having an inert gas filled therein; a pair of sealing electrodes disposed on both sides of the container tube and electrically connected to individual leads; and a surge The absorbing member is electrically connected to the sealing electrode, wherein the surge absorbing unit comprises a non-conductive member, a conductive coating, deposited on the outer surface of the non-conductive member, and at least one discharge gap separating the conductive coating, and is electrically conductive The coating includes a antimony tin oxide containing tin oxide (SnO ₂ ) and antimony oxide (Sb ₂ O ₃ ) and is deposited on the outer surface of the non-conductive coating by a chemical vapor deposition apparatus.

The cerium oxide contained in the conductive plating film has a weight percentage of 0.5% to 5%.

Unlike the conventional sputtering method in which heat treatment is used as a post-treatment, since the surge absorber of the present invention sprays and deposits a deposition solution on the outer surface of the rotated non-conductive member by a CVD method in a high temperature environment, Therefore, an increase in the resistance value due to the heat treatment can be avoided, and the reaction time of the surge absorber of the present invention can be prevented from being reduced due to an increase in the resistance value.

Since the conductive plating film is deposited on the non-conductive element by the CVD method, the conductive plating film can have different resistance values even at the same thickness, and thus it is easy to adjust the thickness of the conductive plating film.

The conductive coating is uniformly deposited on the non-conductive element by a CVD method to a fixed thickness. Thereby, when the surge simulation is performed, the discharge start voltage can be stably settled within a predetermined range every time a surge is applied.

The surge absorber of the present invention will be described below in conjunction with the drawings.

Referring to Fig. 1, a surge absorber 10 of the present invention includes a container tube 11 containing an inert gas, and a pair of sealing electrodes 12 disposed at both ends of the container tube 11 and electrically connected to the individual leads 13 and the surge absorbing member 15. The insulation is disposed in the container tube 11 and the pair of end electrodes 14 are disposed at both ends of the surge absorber 15 and are electrically connected to the sealing electrode 12 and the surge absorbing element 15.

Specifically, the cylindrical container tube 11 is composed of a glass and a ceramic material. The cylindrical container tube 11 is sealed by a sealing electrode 12 at both ends thereof and has an inert gas filled therein.

As described above, the sealing electrode 12 is provided at both ends of the container tube 11 and is electrically connected to the individual lead wires 13.

As described above, the terminal electrodes 14 are provided at both ends of the surge absorber 15 and are electrically connected to the sealing electrode 12 and the surge absorbing element 15. When the sealing electrode 12 is directly electrically connected to the surge absorber 15, the terminal electrode 14 can be omitted.

The surge absorbing member 15 is insulated from the container tube 11. The surge absorbing element 15 includes a non-conductive element 16 and a conductive plating film 17 for blocking the non-conductive element 16 as a discharge electrode and separating at least one discharge gap 18 of the conductive plating film 17.

The non-conductive element 16 is composed of a cylindrical aluminum rod.

The conductive plating film 17 is made of a conductive metal oxide. Specifically, an antimony tin oxide (ATO) coating is deposited on the outer surface of the non-conductive member 16 by a chemical vapor deposition (CVD) apparatus as shown in FIG.

As shown in Fig. 2, the CVD apparatus 20 includes a heating furnace 21 in which a drum 22 is disposed. The drum 22 is provided with a plurality of non-conductive elements 16 and a rotary motor 23 rotatably coupled thereto. The drum 22 is rotated and the drum 22 is rotated, and a sprayer 24 is sprayed to deposit a conductive coating 17 on the non-conductive member 16, and the non-conductive member 16 is deposited in the heating furnace 21.

The sprayer 24 includes a deposition solution storage tank 24a, a valve 24b disposed above the deposition solution storage tank 24a, and a nozzle 24c which is connected to the valve 24b by a hose and spray-deposited to the barrel 22 in the heating furnace 21. Solution. The component symbol 25, which is not mentioned, represents a temperature regulator which maintains the heating furnace 21 at a high temperature. The temperature regulator 25 maintains the temperature inside the heating furnace 21 at 600 degrees Celsius or more.

In summary, the surge absorber 10 of the present invention is fabricated using a CVD process that includes spraying and depositing a deposition solution onto the outer surface of the rotating non-conductive element 16 in a high temperature environment. Conventional methods use a sputtering method followed by post-treatment, or heat treatment to increase the bonding force of the conductive plating film. Unlike the conventional method, when the conductive plating film 17 is deposited on the non-conductive member 16 by the above method, In the upper case, the CVD method does not require heat treatment, so that an increase in the resistance value due to the heat treatment can be avoided.

In addition, when the surge absorber is under a high voltage, the conductive plating film 17 manufactured by a conventional method must be greater than or equal to a predetermined thickness, which is different from the conventional method because the conductive plating film 17 is formed by a CVD method. The surge absorber 10 of the invention is characterized in that the thickness of the conductive plating film 17 can be easily adjusted, and the CVD method can produce a conductive plating film having different resistance values even in the case of the same thickness. At the same time, the CVD method can continuously control the cumulative damage caused by the surge.

Further, the surge absorber 10 of the present invention is characterized in that the conductive plating film 17 is deposited on the outer surface of the non-conductive member 16 by a CVD method, and the conductive plating film 17 can have a fixed thickness. When the surge simulation is performed and the comparison result of the discharge start voltage measured by the surge is applied a plurality of times, the discharge start voltage can be stably settled within a predetermined range every time the surge is applied.

Further, a passivation layer (not shown) can be formed on the outer surface of the conductive plating film 17. The conductive ceramic film can function as a passivation layer. When the gas is discharged, the passivation layer can prevent the discharge energy generated by the gas discharge from being transferred to the conductive plating film, thereby protecting the conductive plating film from damage.

The passivation layer is formed of a conductive ceramic having strong covalent bond characteristics, such as a conductive oxide, a conductive nitride, a conductive carbide, a conductive fluoride, a conductive telluride, or the like.

In other words, the passivation layer formed of the above material has a relatively long reaction time as compared with the conductive plating film 17, but it has a high melting point and has excellent surge resistance and heat resistance. Thereby, it is possible to effectively prevent the discharge energy from being transferred to the conductive plating film.

The discharge gap 18 divides the conductive plating film 17 into a plurality of conductive plating films, and the divided conductive plating film 17 serves as a discharge electrode. Since the discharge energy formed on the discharge gap 18 decreases as the number of the discharge gaps 18 increases, the discharge gap 18 separates the conductive plating film 17 into a plurality of conductive plating films.

Next, a method of manufacturing the surge absorber of the present invention will be described below with reference to FIG.

(a) In order to manufacture the surge absorber 10, first, the non-conductive element 16 is prepared. To this end, the cylindrical aluminum rod is cut to a predetermined length.

(b) The prepared non-conductive element 16 is loaded into the CVD apparatus. The non-conductive member 16 is rotated, and the deposition solution is sprayed onto the outer surface of the non-conductive member 16 in a high-temperature environment of about 600 degrees Celsius or more, and the conductive plating film 17 is thereby deposited. In the present embodiment, the conductive plating film 17 deposited on the non-conductive element 16 is a conductive metal oxide, preferably ATO.

In this manner, the conductive plating film 17 deposited on the non-conductive element 16 is ATO, because if only tin oxide (SnO ₂ ) is deposited on the non-conductive element, it is difficult to obtain a desired resistance value. Therefore, a small amount of bismuth oxide (Sb ₂ O ₃ ) should be included to obtain the desired resistance value.

Specifically, cerium oxide contained in the conductive plating film 17 is a harmful material which is generally used to maintain a temperature coefficient of resistance (TCR). However, since the surge absorber 10 of the present invention does not need to maintain the TCR, the conductive plating film 17 can contain only a small amount of cerium oxide, as described above.

In other words, the conductive plating film 17 of the present invention contains tin oxide and cerium oxide. In the present embodiment, the weight percentage of tin oxide is preferably 95% to 99.5%, and the weight percentage of cerium oxide is preferably 0.5% to 5%.

(C) The terminal electrode 14 is covered at both ends of the non-conductive member 16, and the conductive plating film 17 is deposited on the non-conductive member 16. In this step, if the non-conductive element 16 on which the conductive coating film 17 is deposited on the surge absorber 10 is directly electrically connected to the sealing electrode 12, the covering step can be omitted.

(d) After the terminal electrode 14 is covered, a discharge gap 18 for separating the conductive plating film 17 into a plurality of conductive plating films is formed. The surge absorbing device 15 is thereby completed. The conductive plating film 17 is partitioned so as to discharge the gap 18 so that the divided conductive plating film 17 serves as a discharge electrode.

(e) After the surge absorbing device 15 is completed, the absorption device 15 is then surgely deposited inside the container tube 11, and the sealing electrode 12 is sealed at both ends of the container tube 11, respectively. The inert gas is thereby enclosed in the container tube 11 sealed by the sealed electrode 12. The terminal electrodes 14 provided at both ends of the surge absorbing member 15 are electrically connected to the individual sealing electrodes 12.

The sealing step of sealing the sealing electrode 12 to both ends of the container tube 11 is carried out under a high temperature environment of about 600 degrees Celsius or above. In contrast, the conductive coating of the conventional surge absorber is deposited by sputtering. In this case, the conductive coating may be changed due to the sealing step being manufactured in a high temperature environment. However, in the surge absorber 10 of the present invention, the deposition step of the conductive plating film 17 is performed in a high temperature environment similar to, and preferably higher than, the sealing temperature, so when the sealing step is performed, the conductive plating film does not Subject to stress caused by high temperatures.

(f) After the surge absorbing element 15 is sealed, the lead 13 is connected to the individual sealing electrode 12. Thereby, the surge absorber 10 of the present invention is completed.

Unlike the conventional sputtering method in which heat treatment is used as a post-treatment, since the surge absorber 10 of the present invention is used in a high temperature environment, a deposition solution is sprayed and deposited on the outer surface of the non-conductive member 16 to be rotated using a CVD method. Therefore, it is possible to avoid an increase in the resistance value due to the heat treatment, and to prevent the reaction time of the surge absorber 10 of the present invention from being decreased due to an increase in the resistance value.

As described above, since the surge absorber 10 of the present invention deposits the conductive plating film 17 on the non-conductive member 16 by the CVD method, the conductive plating film can have different resistance values even at the same thickness, and thus it is easy to adjust. The thickness of the conductive plating film 17.

As described above, since the surge absorber of the present invention uniformly deposits the conductive plating film 17 on the non-conductive member 16 by a CVD method, when the surge simulation is performed, the amount of surge is applied every time. The discharge starting voltage can stably fall within a predetermined range.

Further, as described above, since the surge absorber 10 of the present invention deposits the conductive plating film 17 on the non-conductive element 16 by the CVD method, and the conductive plating film 17 is composed of ATO containing germanium, it is possible to provide a surge. The absorber 10 has a predetermined resistance value. In the present embodiment, since the ATO used is a hazardous material, it is preferably used in a small amount. In the surge absorber 10 of the present invention, it is not necessary to maintain the TCR, so that when the conductive plating film 17 is deposited, it can contain only a small amount of harmful ruthenium.

Further, as described above, unlike the conventional method in which the conductive plating film 17 is changed in the sealing step of the sealing electrode 12, since the conductive plating film 17 of the surge absorber 10 of the present invention is in a high temperature environment, deposition is performed using a CVD method. The solution is sprayed and deposited on the outer surface of the non-conductive element 16 being rotated, so that the conductive coating is not subjected to stress caused by high temperature.

The invention has been disclosed above by several embodiments. The skilled artisan will be able to design or modify other processes or architectures based on the technical aspects disclosed herein to achieve the objects and/or advantages of the present invention. It will be appreciated by those skilled in the art that a number of changes, substitutions and substitutions can be made without departing from the spirit and scope of the invention. The scope of the invention is determined by the scope of the appended claims.

10. . . Surge absorber

11. . . Container tube

12. . . Sealed electrode

13. . . lead

14. . . Terminal electrode

15. . . Surge absorption component

16. . . Non-conductive component

17. . . Conductive coating

18. . . Discharge gap

20. . . CVD equipment

twenty one. . . Heating furnace

twenty two. . . Bucket

twenty three. . . Rotary motor

twenty four. . . sprayer

24a. . . Deposition solution storage tank

24b. . . valve

24c. . . nozzle

25. . . temperature regulator

Those skilled in the art will be able to understand the above and other objects, features and advantages of the present invention in light of the above-described embodiments.

Figure 1 is a cross-sectional view of a surge absorber of a specific embodiment of the present invention;

Figure 2 illustrates a CVD apparatus for fabricating a surge absorber of a particular embodiment of the present invention;

Fig. 3 (a) to (f) are schematic views showing a method of manufacturing a surge absorber according to a specific embodiment of the present embodiment.

10. . . Surge absorber

11. . . Container tube

12. . . Sealed electrode

13. . . lead

14. . . Terminal electrode

15. . . Surge absorption component

16. . . Non-conductive component

17. . . Conductive coating

18. . . Discharge gap

Claims (3)

A method of fabricating a surge absorber comprising: preparing a non-conductive element; depositing a conductive coating on an outer surface of the non-conductive element using a chemical vapor deposition method, wherein the conductivity The coating comprises a bismuth tin oxide containing 0.5% to 5% by weight of cerium oxide, wherein the chemical vapor deposition method rotates the non-conductive element and sprays a deposition solution in a high temperature environment; In the coating, at least one discharge gap is formed to constitute a surge absorbing member; in the container tube, the surge absorbing member is deposited, and in the container tube, the plurality of sealing electrodes are sealed in the container tube The container tube has an inert gas filled therein, wherein the deposition step of the conductive plating film is performed at 600 degrees Celsius or higher and higher than the temperature used in the sealing step; and the lead is electrically connected to the individual The above sealed electrode. A surge absorber includes: a container tube having an inert gas filled therein; a pair of sealing electrodes disposed on both sides of the container tube and electrically connected to individual leads; and a surge absorbing member, electricity Connecting to the sealed electrode; wherein the surge absorbing unit comprises a non-conductive element, a conductive coating deposited on an outer surface of the non-conductive element, and at least one discharge gap separating the conductive coating And the conductive plating film includes a antimony tin oxide containing tin oxide (SnO ₂ ) and antimony oxide (Sb ₂ O ₃ ) and is deposited on the outer surface of the non-conductive plating film by a chemical vapor deposition apparatus. . The surge absorber according to claim 2, wherein the cerium oxide contained in the conductive plating film has a weight percentage of 0.5% to 5%.