Arc breaking prevention electrode

Abstract

The utility model discloses an arc breaking prevention electrode which comprises an electrode body and an electrode primer arranged at the front end of the electrode body, and the diameter of the electrode primer is smaller than that of the electrode body. According to the arc breaking prevention electrode, on the basis that the electrode body is not combusted, the electrode primer is combusted firstly, heat generated by combustion of the electrode primer is gradually transmitted to the electrode body, and therefore after red hot arc discharge of the electrode primer is stable, preheating of the electrode body can be gradually guided, and stable arc starting can be achieved after the electrode body is preheated; the frequency of electrode arc breaking is reduced, the stability of the material melting process is improved, and the quality of the crucible is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor material manufacturing tools, and more specifically to an arc breaking prevention electrode. Background Art

[0002] Single crystal silicon is an indispensable basic material in modern science and technology. For example, electronic computers and automatic control systems in daily life, as well as televisions, computers, refrigerators, telephones, watches and cars are inseparable from single crystal silicon materials. Single crystal silicon has penetrated into every corner of people's lives. Single crystal is a crystal with a basically complete lattice structure. Different directions have different properties. It is a good semiconductor material with a purity requirement of 99.9999%, or even more than 99.9999999%. It is made by putting high-purity polycrystalline silicon into a quartz crucible in a single crystal furnace. In this case, the relevant technicians attach great importance to the purity of the quartz crucible and the problem of microbubbles, which not only affects the purity of the single crystal silicon ingot, but also plays a vital role in pulling single crystals. Specifically, a layer of micron-sized microbubbles will be formed when preparing the quartz crucible, mainly existing within a depth of 1 mm on the inner surface of the quartz crucible. During the growth of the single crystal silicon rod, the microbubbles in the quartz crucible slowly expand under a continuous high temperature environment, and then merge into larger microbubbles. Once they break, they will bring quartz fragments and impurities into the molten silicon liquid, intensifying the reaction between the quartz crucible and the molten silicon liquid, causing the silicon liquid level at the liquid level line inside the quartz crucible to vibrate, resulting in crystal pulling failure or wire breakage.

[0003] Therefore, the quality of the quartz crucible is one of the determining factors for the quality of single crystal silicon, especially in the semiconductor industry, which has extremely stringent requirements on the purity of single crystal silicon and is much more difficult to manufacture than in the photovoltaic industry. Therefore, the quartz crucible used to prepare semiconductor-grade single crystal silicon is a difficult point in crucible manufacturing. In the existing process of melting and making crucibles using the arc method, the electrode body begins to burn after the electrode arcs, and the diameter of the electrode head is relatively large. When the electrode is placed for a long time, the temperature is too low, and the arc is easily broken when the arc is struck. This causes difficulty in arcing the electrode and even fluctuations in the melting process, which ultimately leads to fluctuations in product quality. Utility Model Content

[0004] In order to solve the above technical problems, the utility model provides an anti-arc breaking electrode, which can gradually guide the preheating of the electrode body after the electrode initiator is red-hot and the arc is stable. After the electrode body is preheated, the arc can be stably started, the frequency of electrode arc breaking is reduced, the stability of the material melting process is improved, and the quality of the crucible is improved.

[0005] The utility model provides an arc-breaking prevention electrode, which comprises an electrode body and an electrode lead arranged at the front end of the electrode body, wherein the diameter of the electrode lead is smaller than the diameter of the electrode body.

[0006] Preferably, in the above-mentioned arc-breaking prevention electrode, the shape of the electrode lead is cylindrical or hemispherical.

[0007] Preferably, in the above-mentioned arc-breaking prevention electrode, the diameter of the electrode lead is one half to two thirds of the diameter of the electrode body.

[0008] Preferably, in the above-mentioned arc-breaking prevention electrode, the length of the electrode lead along the axial direction of the electrode body ranges from one half to two thirds of the diameter of the electrode body.

[0009] Preferably, in the above-mentioned arc-breaking prevention electrode, the electrode body comprises a graphite electrode directly fixed to the electrode lead.

[0010] Preferably, in the above-mentioned arc-breaking prevention electrode, one end of the graphite electrode away from the electrode lead is also connected to a copper electrode.

[0011] Preferably, in the above-mentioned arc-breaking prevention electrode, the copper electrode and the graphite electrode are connected together by an electrode joint.

[0012] Preferably, in the above-mentioned arc-breaking prevention electrode, the electrode joint is in the shape of a hollow sleeve, which includes a first hollow portion and a second hollow portion that are adjacent and communicating with each other, the inner diameter of the first hollow portion is the same as the diameter of the portion where the graphite electrode is inserted into the first hollow portion, the inner diameter of the second hollow portion is the same as the diameter of the portion where the copper electrode is inserted into the second hollow portion, and the graphite electrode and the copper electrode are coaxially electrically connected together inside the electrode joint.

[0013] Preferably, in the above-mentioned arc-breaking prevention electrode, the diameter of the copper electrode ranges from 80 mm to 100 mm.

[0014] Preferably, in the above-mentioned arc-breaking prevention electrode, the electrode joint is a graphite electrode joint.

[0015] It can be seen from the above technical scheme that the above-mentioned anti-arc breaking electrode provided by the utility model includes an electrode body and an electrode inducer arranged at the front end of the electrode body, and the diameter of the electrode inducer is smaller than the diameter of the electrode body. Therefore, the electrode inducer can be burned first without burning the electrode body, and the heat generated by the burning of the electrode inducer can be gradually transferred to the electrode body. Therefore, this scheme can gradually guide the preheating of the electrode body after the red-hot arc drawing of the electrode inducer is stable. After the electrode body is preheated, it can stably start the arc, reduce the frequency of electrode arc breaking, improve the stability of the material melting process, and improve the quality of the crucible. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0017] Figure 1 A schematic diagram of an embodiment of an arc-breaking prevention electrode provided by the utility model;

[0018] Figure 2 A schematic diagram of the overall composition of another specific embodiment of the arc-breaking prevention electrode provided by the present application;

[0019] Figure 3 This is a schematic diagram of the exploded components of another specific embodiment of the arc-breaking prevention electrode provided in the present application. DETAILED DESCRIPTION

[0020] The core of the utility model is to provide an anti-arc breaking electrode, which can gradually guide the preheating of the electrode body after the electrode initiator is red hot and the arc is stable. After the electrode body is preheated, the arc can be stably started, the frequency of electrode arc breaking is reduced, the stability of the material melting process is improved, and the quality of the crucible is improved.

[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] The utility model provides an arc-breaking prevention electrode. Figure 1 As shown, Figure 1 A schematic diagram of an embodiment of an arc-breaking prevention electrode provided by the utility model, the embodiment of the arc-breaking prevention electrode may include an electrode body 1 and an electrode lead 2 arranged at the front end of the electrode body 1, the diameter of the electrode lead 2 is smaller than the diameter of the electrode body 1, this type of arc-breaking prevention electrode can process the entire blank by lathe, the electrode body 1 and the electrode lead 2 can be lathe-machined at one time, so the two themselves are connected as a whole.

[0023] It should be noted that from Figure 1It can be seen that the diameter of the electrode initiator 2 is obviously smaller than the front end of the electrode body 1 and the adjacent part thereof. The specific diameter size can be selected according to actual needs. Due to the difference in diameter, the electrode initiator 2 can burn under relatively small voltage and current conditions (voltage 250V and current 2500A can be selected), while the electrode body 1 will not burn. This is similar to the fact that a smaller flame can only ignite thinner firewood but cannot ignite thicker firewood. In this way, the heat generated by the continuous burning of the electrode initiator 2 can be conducted to the electrode body 1. After a period of time, various parts of the electrode body 1 can be preheated and will no longer be in a cold state. At this time, a larger voltage and a larger current (voltage 300V and current 3000A can be selected) can be applied to start the arc and burn the electrode body 1. Since various parts of the electrode body 1 have undergone a preheating process and have a relatively uniform temperature distribution, the arc will not be easily broken, thereby ensuring that the material melting process is more stable.

[0024] It can be seen from the above technical scheme that the above-mentioned anti-arc breaking electrode provided by the utility model includes an electrode body and an electrode inducer arranged at the front end of the electrode body, and the diameter of the electrode inducer is smaller than the diameter of the electrode body. Therefore, the electrode inducer can be burned first without burning the electrode body, and the heat generated by the burning of the electrode inducer can be gradually transferred to the electrode body. Therefore, the scheme can gradually guide the arc starting preheating of the electrode body after the red-hot arc pulling of the electrode inducer is stable. After the electrode body is preheated, the arc can be stably started, the frequency of electrode arc breaking can be reduced, the stability of the material melting process can be improved, and the quality of the crucible can be improved.

[0025] In a specific embodiment of the above-mentioned arc-breaking prevention electrode, the shape of the electrode lead 2 can be preferably cylindrical or hemispherical, and both shapes are symmetrical relative to the axial center of the electrode body, so the heat dissipation paths in all directions are the same, so that the uniformity of heat transfer to the electrode body 1 can be better guaranteed, and the problem of some parts being hot and some parts being cold will not be caused. Further, the diameter of the electrode lead 2 can be preferably one-half to two-thirds of the diameter of the electrode body 1, specifically 43mm to 63mm, and more preferably 53mm. This range can ensure that the electrode lead 2 can arc and burn independently, and can also ensure that the electrode lead 2 has a sufficiently large contact area with the electrode body 1, thereby ensuring a sufficiently high heat transfer efficiency, allowing heat to be transferred to the electrode body 1 more quickly to achieve its preheating. Furthermore, the length range of the electrode initiator 2 along the axial direction of the electrode body 1 can be preferably one-half to two-thirds of the diameter of the electrode body 1, specifically 43mm to 63mm, and more preferably 53mm. This length can ensure that there is enough volume for arc starting and burning, and generate enough heat, and the arc breaking rate of the electrode is significantly reduced, the arc starting process is more stable, and the quality of the crucible is effectively improved. Of course, the diameter and length of the above-mentioned electrode initiator can also be adaptively adjusted according to actual needs, which is not limited here.

[0026] In another specific embodiment of the arc-breaking prevention electrode, Figure 2 , Figure 2 A schematic diagram of the overall composition of another specific embodiment of the arc-breaking prevention electrode provided in the present application, wherein the electrode body 1 includes a graphite electrode 11 directly fixed to the electrode lead 2, and the graphite electrode 11 is used as a tool for transmitting current and generating arc light, thereby melting the quartz sand in the mold and melting the quartz crucible. This graphite electrode 11 will burn and be consumed during the discharge process, and transfer the heat to the material inside the mold to achieve the melting of the material. The graphite electrode can be replaced after working for a certain period of time, and the end of the graphite electrode 11 away from the electrode lead 2 can also be connected to a copper electrode 12. This copper electrode is a non-consumable item used to achieve the transmission of electrical energy. Furthermore, the copper electrode 12 and the graphite electrode 11 can preferably be connected together using an electrode connector 13. This electrode connector can ensure the stable connection and conductivity of the two electrodes, and can also achieve more convenient replacement of the graphite electrode.

[0027] In another specific embodiment of the arc-breaking prevention electrode, Figure 3 , Figure 3It is a schematic diagram of the components of another specific embodiment of the arc-breaking prevention electrode provided in the present application after being decomposed. It can be seen that the electrode joint 13 can preferably be a hollow sleeve, including a first hollow portion 131 and a second hollow portion 132 that are adjacent and connected. The inner diameter of the first hollow portion 131 is the same as the diameter of the portion where the graphite electrode 11 is inserted into the first hollow portion 131, and the inner diameter of the second hollow portion 132 is the same as the diameter of the portion where the copper electrode 12 is inserted into the second hollow portion 132. The graphite electrode 11 and the copper electrode 12 are coaxially electrically connected together inside the electrode joint 13. It should be noted that, during installation, a firm connection can be achieved by simply inserting the graphite electrode 11 and the copper electrode 12 into the electrode connector 13 from both ends. It can further be preferably an interference fit, that is, the diameter of the portion where the graphite electrode 11 is inserted into the first hollow portion 131 can be slightly larger than the inner diameter of the first hollow portion 131, and the diameter of the portion where the copper electrode 12 is inserted into the second hollow portion 132 can be slightly larger than the inner diameter of the second hollow portion 132, and the stability of current transmission can be ensured. When the graphite electrode or copper electrode needs to be replaced, it can also be conveniently pulled out for quick replacement. Of course, this is only one form of connection, and other connection methods can be selected according to actual needs, such as welding, bonding, etc., which are not limited here.

[0028] In a preferred embodiment of the above-mentioned arc-breaking prevention electrode, the diameter range of the copper electrode 12 can be preferably 80 mm to 100 mm, so that it can withstand the required voltage and current, and the above-mentioned electrode connector 13 can be preferably a graphite electrode connector, which is more matched with the material of the graphite electrode 11, ensuring smoother current transmission and more consistent heat generation. Of course, other materials can also be selected according to actual needs, as long as the following conditions are met: conductive and resistivity greater than 6Ω·cm; ash content less than 200ppm; corrosion resistant.

[0029] It should be noted that the working process of the above-mentioned anti-arc breaking electrode is as follows: first, after the arc is started, the electrode initiator 2 is heated to form a stable arc at the position of the electrode initiator 2, and then the electrode initiator 2 is continuously burned and consumed, and the heat is conducted to the electrode body 1, so that the electrode body 1 is slowly preheated. When the electrode body 1 draws the arc, the entire electrode is already in a red-hot state, so that arc breaking will not occur in the subsequent process, ensuring that the melting process is more stable.

[0030] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An arc-breaking prevention electrode, characterized in that: It comprises an electrode body and an electrode lead arranged at the front end of the electrode body, wherein the diameter of the electrode lead is smaller than the diameter of the electrode body.

2. The arc-breaking prevention electrode according to claim 1, characterized in that: The electrode lead is in the shape of a cylinder or a hemisphere.

3. The arc-breaking prevention electrode according to claim 2, characterized in that: The diameter of the electrode lead is one half to two thirds of the diameter of the electrode body.

4. The arc-breaking prevention electrode according to claim 1, characterized in that: The length of the electrode lead along the axial direction of the electrode body ranges from one half to two thirds of the diameter of the electrode body.

5. The arc-breaking prevention electrode according to any one of claims 1 to 4, characterized in that: The electrode body includes a graphite electrode directly fixed to the electrode lead.

6. The arc-breaking prevention electrode according to claim 5, characterized in that: One end of the graphite electrode away from the electrode lead is also connected to a copper electrode.

7. The arc-breaking prevention electrode according to claim 6, characterized in that: The copper electrode and the graphite electrode are connected together using an electrode joint.

8. The arc-breaking prevention electrode according to claim 7, characterized in that: The electrode joint is in the shape of a hollow sleeve, including a first hollow portion and a second hollow portion that are adjacent and interconnected, the inner diameter of the first hollow portion is the same as the diameter of the portion where the graphite electrode is inserted into the first hollow portion, the inner diameter of the second hollow portion is the same as the diameter of the portion where the copper electrode is inserted into the second hollow portion, and the graphite electrode and the copper electrode are coaxially electrically connected together inside the electrode joint.

9. The arc-breaking prevention electrode according to claim 6, characterized in that: The diameter of the copper electrode ranges from 80 mm to 100 mm.

10. The arc-breaking prevention electrode according to claim 7, characterized in that: The electrode joint is a graphite electrode joint.

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