CN115014084A - Sintering furnace and method for preparing tantalum carbide coating on surface of graphite substrate - Google Patents

Abstract

The embodiment of the application provides a sintering furnace and a method for preparing a tantalum carbide coating on the surface of a graphite substrate. The sintering furnace is used for sintering the tantalum carbide coating on the graphite substrate. The sintering furnace comprises a furnace shell, a first electrode and a second electrode. A cavity is formed inside the furnace shell and is configured as an accommodating space for the sintered graphite substrate. One end of the first electrode is in contact with one side of the graphite substrate, and one end of the second electrode is in contact with the other side of the graphite substrate, and when a voltage is applied to the first electrode and the second electrode, the first electrode, the second electrode and the graphite substrate form a conductive loop. The graphite substrate sintered by the sintering furnace in the embodiment has no loss, the subsequent crystal growth quality is ensured, the service life of the graphite substrate can be further prolonged, and a heater is not required to be arranged, so that the production cost is effectively reduced, and the industrial production is facilitated.

Description

Sintering furnace and method for preparing tantalum carbide coating on surface of graphite substrate

Technical Field

The application relates to the field of preparation of tantalum carbide coatings, in particular to a sintering furnace and a method for preparing a tantalum carbide coating on the surface of a graphite substrate.

Background

This section provides background information related to the present application that is not necessarily prior art.

In the related art, in the field of semiconductor crystal growth, devices of graphite materials, such as graphite heaters, graphite crucibles, jigs, and the like, are widely used. Graphite materials have many unique properties, such as: the material is a good conductor of heat and electricity, has the characteristics of high chemical stability, high temperature resistance, small thermal expansion coefficient, strong thermal shock resistance, easy processing, lower price than tungsten, molybdenum and tantalum and the like, and is an important inorganic non-metallic material.

The growth environment temperature of the third-generation semiconductor crystal is as high as 2100-2400 ℃, a complex atmosphere environment exists in a growth space with a small size, the sublimation source powder (silicon and aluminum) atmosphere has high reaction activity and can erode a graphite material device, particles on the surface of the graphite material device enter the crystal to cause crystal defects such as a wrapping object and the like, and further great influence is generated on the performance and quality of the crystal and the semiconductor, and the problem can be well solved by increasing the coverage of a tantalum carbide coating on the surface of the graphite material.

The tantalum carbide is a high-temperature ceramic material with high melting point (3880 ℃), high strength and good chemical stability, and has the characteristics of excellent chemical corrosion resistance and oxidation resistance under a high-temperature environment, so that the tantalum carbide can be used as a high-temperature coating to be applied to the surface of a graphite material device, the device is endowed with more excellent corrosion resistance, and the protection effect is effectively realized, thereby playing the roles of reducing defects, improving the crystal quality, increasing the reuse rate of the graphite material device and reducing the generation cost in the actual crystal growth of a third-generation semiconductor.

At present, the method for preparing the tantalum carbide coating at low cost at home and abroad is generally adopted as follows: preparing turbid liquid by adopting tantalum carbide, sintering aid, adhesive and solvent, uniformly spraying or brushing the turbid liquid on the surface of the graphite device, and finally performing preheating and sintering treatment on the device sprayed or brushed with the coating to obtain a tantalum carbide coating on the device. The method inevitably needs to sinter the graphite device with the tantalum carbide turbid liquid, the sintering mode is mainly adopted and is that an external heater is used for heating around the device, the graphite material device directly faces to a heating source, local oxidation is easy to occur, the service life of the graphite material device is reduced, even the subsequent crystal growth quality is influenced, and the external heater is easy to generate loss after being used for a long time, so that the cost is increased, and therefore, the problem that how to prolong the service life of the graphite material is needed to be solved at present is solved.

Disclosure of Invention

The purpose of the application is to provide a sintering furnace and a method for preparing a tantalum carbide coating on the surface of a graphite substrate so as to prolong the service life of a graphite device. In order to achieve the above purpose, the present application provides the following technical solutions:

embodiments of the first aspect of the present application provide a sintering furnace for sintering a tantalum carbide coating on a graphite substrate. The sintering furnace comprises a furnace shell, a first electrode and a second electrode. A cavity is formed inside the furnace shell and is configured as an accommodating space for the sintered graphite substrate. One end of the first electrode is in contact with one side of the graphite substrate, and one end of the second electrode is in contact with the other side of the graphite substrate, and when a voltage is applied to the first electrode and the second electrode, the first electrode, the second electrode and the graphite substrate form a conductive loop.

According to the fritting furnace in this application embodiment, when sintering the graphite base member, can arrange the graphite base member that the coating had the tantalum carbide turbid liquid in the cavity earlier, then do not coat the position of tantalum carbide turbid liquid with the graphite base member respectively with first electrode and second electrode electric connection, when exerting voltage for first electrode and second electrode, first electrode, second electrode and graphite base member form conductive loop, because the graphite base member is the graphite material, consequently this graphite base member can generate heat when switching on, and then utilize the graphite base member of the spontaneous heating sintering coating of graphite base member to have the graphite base member of tantalum carbide suspension. The graphite substrate sintered by the sintering furnace in the embodiment has no loss, the subsequent crystal growth quality is ensured, the service life of the graphite substrate can be further prolonged, and a heater is not required to be arranged, so that the production cost is effectively reduced, and the industrial production is facilitated.

In addition, according to the embodiment of the application, the following additional technical features can be provided:

in some embodiments of this application, the stove outer covering includes first bell, second bell and side stove bucket, first bell with the second bell sets up respectively the both ends of side stove bucket, first bell second bell with side stove bucket surrounds formation the cavity.

In some embodiments of the present application, the first electrode comprises a first graphite electrode and a first metal electrode, the first graphite electrode and the first metal electrode being electrically connected, the first graphite electrode being configured to be connected to a portion of the graphite substrate.

In some embodiments of the present application, the second electrode comprises a second graphite electrode and a second metal electrode, the second graphite electrode and the second metal electrode being electrically connected, the second graphite electrode being configured to be connected to a portion of the graphite substrate.

In some embodiments of the present application, the sintering furnace further includes a heat preservation chamber, the heat preservation chamber is disposed in the cavity, a vacuum chamber is formed inside the heat preservation chamber, the heat preservation chamber further includes an air inlet and an air outlet communicated with the vacuum chamber, a graphite substrate to be sintered is disposed in the vacuum chamber, and the first electrode and the second electrode pass through the heat preservation chamber and are connected with a part of the graphite substrate.

Embodiments of the second aspect of the present application propose a method for preparing a tantalum carbide coating on the surface of a graphite substrate, which is implemented based on the sintering furnace in any one of the embodiments of the first aspect, and the method comprises the following steps:

placing the graphite substrate coated with the tantalum carbide turbid liquid in the sintering furnace;

communicating one side, which is not coated with the tantalum carbide turbid liquid, of the graphite matrix with the first electrode and the second electrode respectively;

applying a voltage to the first electrode and the second electrode to cause the first electrode, the second electrode, and the graphite matrix to form a circuit.

In some embodiments of the present application, the sintering furnace further includes a heat preservation chamber, the heat preservation chamber is disposed in the cavity, a vacuum chamber is disposed inside the heat preservation chamber, and an air inlet and an air outlet communicated with the vacuum chamber, the step of placing the graphite substrate coated with the tantalum carbide suspension in the sintering furnace includes,

and placing the graphite matrix coated with the tantalum carbide turbid liquid in the vacuum chamber, and enabling the vacuum chamber to be in a vacuum state.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Like parts are designated with like reference numerals throughout the drawings. In the drawings:

FIG. 1 is a schematic view showing a structure of a sintering furnace in a sintering process in the related art;

FIG. 2 is a schematic structural diagram of a sintering furnace in the sintering process in the embodiment of the application;

FIG. 3 is a front view of a sintering furnace in an embodiment of the present application;

FIG. 4 is a plan view of a sintering furnace in an embodiment of the present application;

fig. 5 is a sectional view taken along the line a-a in fig. 4.

The reference symbols in the drawings denote the following:

10-a graphite matrix; 20-tantalum carbide suspension; 30-a heater;

100-furnace shell; 110-a first furnace cover; 120-a second furnace cover; 130-side furnace barrel; -140 a cavity;

210-a first electrode; 211-a first metal electrode; 212 — a first graphite electrode; 220-a second electrode; 221-a second metal electrode; 222-a second graphite electrode;

300-a heat preservation cavity; 310-vacuum chamber.

Detailed Description

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the description below are only some embodiments of the present application, and other embodiments can be obtained by those skilled in the art according to the drawings.

For convenience of description, spatially relative terms, such as "inner", "outer", "lower", "below", "upper", "above", and the like, may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments that can be derived by one of ordinary skill in the art from the description herein are intended to be within the scope of the present disclosure.

In the related technology, the method for preparing the tantalum carbide coating at low cost at home and abroad is generally adopted as follows: preparing turbid liquid by adopting tantalum carbide, sintering aid, adhesive and solvent, uniformly spraying or brushing the turbid liquid on the surface of the graphite device, and finally performing pre-heating and sintering treatment on the device sprayed or brushed with the coating to obtain a tantalum carbide coating on the device. The method inevitably needs to sinter the graphite device with the tantalum carbide turbid liquid, the sintering mode is mainly adopted and is that an external heater is used for heating around the device, the graphite material device directly faces to a heating source, local oxidation is easy to occur, the service life of the graphite material device is reduced, even the subsequent crystal growth quality is influenced, and the external heater is easy to generate loss after being used for a long time, so that the cost is increased, and therefore, the problem that how to prolong the service life of the graphite material is needed to be solved at present is solved.

As shown in fig. 1, a schematic structural diagram of a graphite device heated by an external heater is illustrated, in which a powdered substance exists on an outer surface of the graphite device sintered by this method, that is, the graphite device sintered by this method affects the quality of grown crystals, thereby reducing the service life of the graphite device, and the graphite device heated by the external heater consumes more energy, thereby inevitably increasing the production cost.

As shown in fig. 2 to 5, embodiments of the first aspect of the present application propose a sintering furnace for sintering a tantalum carbide coating on a graphite substrate 10. The sintering furnace comprises a furnace shell 100, a first electrode 210 and a second electrode 220. The furnace shell 100 has a cavity 140 formed therein, and the cavity 140 is configured as a housing space for the sintered graphite base 10. One end of the first electrode 210 is in contact with one side of the graphite base 10 and one end of the second electrode 220 is in contact with the other side of the graphite base 10, and when a voltage is applied to the first electrode 210 and the second electrode 220, the first electrode 210, the second electrode 220, and the graphite base 10 form a conductive loop.

Referring to fig. 2, according to the sintering furnace in the embodiment of the present application, when sintering the graphite substrate 10, the graphite substrate 10 coated with the tantalum carbide suspension 20 may be placed in the cavity 140, and then the portion of the graphite substrate 10 not coated with the tantalum carbide suspension 20 is electrically connected to the first electrode 210 and the second electrode 220, respectively, when a voltage is applied to the first electrode 210 and the second electrode 220, the first electrode 210, the second electrode 220 and the graphite substrate 10 form a conductive loop, and since the graphite substrate 10 is made of graphite, the graphite substrate 10 can generate heat when being conducted, and then the graphite substrate 10 coated with the tantalum carbide suspension is sintered by self-heating of the graphite substrate 10. The graphite matrix 10 sintered by the sintering furnace in the embodiment has no loss, so that the subsequent crystal growth quality is ensured, the service life of the graphite matrix 10 can be prolonged, and the heater 30 is not required, so that the production cost is effectively reduced, and the industrial production is facilitated.

In some embodiments of the present disclosure, the material of the graphite matrix 10 may be graphite or carbon fiber reinforced carbon parts.

Referring to fig. 3 to 5, in some embodiments of the present disclosure, the furnace shell 100 includes a first furnace cover 110, a second furnace cover 120, and a side furnace barrel 130, the first furnace cover 110 and the second furnace cover 120 are respectively disposed at two ends of the side furnace barrel 130, and the first furnace cover 110, the second furnace cover 120, and the side furnace barrel 130 surround to form a cavity 140. In this embodiment, the first furnace cover 110 may also be referred to as an upper furnace cover, the second furnace cover 120 may also be referred to as a lower furnace cover, and sealing members may be disposed between the first furnace cover 110 and the side furnace barrel 130 and between the second furnace cover 120 and the side furnace barrel 130, so as to ensure the sealing performance of the sintering furnace. When sintering the graphite substrate 10, the graphite substrate 10 to be sintered may be placed in a cavity 140 defined by the first furnace cover 110, the second furnace cover 120, and the side furnace barrel 130.

In some embodiments of the present application, the first electrode 210 includes a first graphite electrode 212 and a first metal electrode 211, the first graphite electrode 212 and the first metal electrode 211 are electrically connected, and the first graphite electrode 212 is configured to be connected to a portion of the graphite substrate 10. In this embodiment, the first metal electrode 211 may be a copper electrode, and since copper is inexpensive and has superior conductivity, it may be used to fabricate the first metal electrode 211. The first metal electrode 211 and the first graphite electrode 212 may be detachably connected, for example, the first metal electrode 211 may be connected to the first graphite electrode 212 by a screw fastening connection.

In some embodiments of the present application, the second electrode 220 includes a second graphite electrode 222 and a second metal electrode 221, the second graphite electrode 222 is electrically connected to the second metal electrode 221, and the second graphite electrode 222 is configured to be connected to a portion of the graphite substrate 10. In this embodiment, the second metal electrode 221 may be a copper electrode, and since copper is inexpensive and has superior conductivity, it can be used to fabricate the second metal electrode 221. The second metal electrode 221 and the second graphite electrode 222 may be detachably connected, for example, the second metal electrode 221 may be connected to the second graphite electrode 222 by screwing.

In some embodiments of the present application, the sintering furnace further includes a heat preservation chamber 300, the heat preservation chamber 300 is disposed in the cavity 140, a vacuum chamber 310 is formed inside the heat preservation chamber 300, the heat preservation chamber 300 further includes an air inlet and an air outlet communicated with the vacuum chamber 310, the graphite substrate 10 to be sintered is disposed in the vacuum chamber 310, and the first electrode 210 and the second electrode 220 are connected to a portion of the graphite substrate 10 through the heat preservation chamber. In this embodiment, the insulated chamber 300 may include a plurality of insulated sidewalls that surround the vacuum chamber 310. The first electrode 210 and the second electrode 220 are both arranged through the insulating cavity 300 and connected with the graphite substrate 10. By arranging the heat preservation cavity 300, the graphite substrate 10 to be sintered can be in a relatively stable sintering environment. It can be understood that the sintering needs to be performed in a specific atmosphere or vacuum, so it is very important to control the gas phase partial pressure during the sintering process, and when the graphite substrate 10 is sintered, the inert gas can be introduced into the gas inlet or the vacuum chamber 310 can be formed inside the heat preservation chamber 300 through the gas outlet, so that the gas phase partial pressure during the sintering process can be ensured, and the preparation of the tantalum carbide coating on the surface of the graphite substrate 10 is facilitated.

Embodiments of the second aspect of the present application provide a method for preparing a tantalum carbide coating on the surface of a graphite substrate, which is implemented based on the sintering furnace in any one of the embodiments of the first aspect, and the method comprises the following steps:

s10, placing the graphite matrix 10 coated with the tantalum carbide suspension liquid 20 in a sintering furnace;

s20, connecting the first electrode 210 and the second electrode 220 to the side of the graphite substrate 10 not coated with the tantalum carbide suspension 20;

s30, applying a voltage to the first electrode 210 and the second electrode 220 to form a circuit of the first electrode 210, the second electrode 220 and the graphite substrate 10.

According to the method for preparing the tantalum carbide coating on the surface of the graphite substrate 10 in the embodiment of the application, since it uses the sintering furnace of any of the embodiments of the first aspect to prepare the tantalum carbide coating on the surface of the graphite substrate 10, it also has the advantages of any of the embodiments of the first aspect, specifically, when sintering the graphite substrate 10, the graphite substrate 10 coated with the tantalum carbide suspension 20 may be placed in the cavity 140, then electrically connecting the parts of the graphite matrix 10 not coated with the tantalum carbide suspension 20 with the first electrode 210 and the second electrode 220 respectively, when a voltage is applied to the first electrode 210 and the second electrode 220, the first electrode 210, the second electrode 220, and the graphite substrate 10 form a conductive circuit, because the graphite matrix 10 is made of graphite, the graphite matrix 10 can generate heat when being conducted, the graphite substrate 10 coated with the tantalum carbide suspension is then sintered by self-heating of the graphite substrate 10. The graphite matrix 10 sintered by the sintering furnace in the embodiment has no loss, so that the subsequent crystal growth quality is ensured, the service life of the graphite matrix 10 can be prolonged, and the heater 30 is not required, so that the production cost is effectively reduced, and the industrial production is facilitated.

In some embodiments of the present application, the sintering furnace further includes a holding chamber 300, the holding chamber 300 is disposed in the cavity 140, a vacuum chamber 310 is disposed inside the holding chamber 300, and an air inlet and an air outlet communicated with the vacuum chamber 310, and the step of placing the graphite substrate 10 coated with the tantalum carbide suspension 20 in the sintering furnace includes,

s11, the graphite substrate 10 coated with the tantalum carbide suspension 20 is placed in the vacuum chamber 310, and the vacuum chamber 310 is kept in a vacuum state.

In this embodiment, when sintering the graphite substrate 10, inert gas may be introduced into the gas inlet or the vacuum chamber 310 may be formed inside the thermal insulation chamber 300 through the gas outlet, so as to ensure the gas phase partial pressure during the sintering process, which is beneficial to prepare the tantalum carbide coating on the surface of the graphite substrate 10.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The embodiments of the present application are described in a related manner, and the same and similar parts among the embodiments can be referred to each other, and each embodiment focuses on the differences from the other embodiments.

The above description is only for the preferred embodiment of the present application and is not intended to limit the scope of the present application. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application are included in the protection scope of the present application.

Claims (7)

1. A sintering furnace for sintering a tantalum carbide coating on a graphite substrate, the sintering furnace comprising:

the furnace shell is internally provided with a cavity, and the cavity is configured into an accommodating space for sintering the graphite substrate;

and a first electrode and a second electrode, one end of the first electrode being in contact with one side of the graphite base body and one end of the second electrode being in contact with the other side of the graphite base body, the first electrode, the second electrode and the graphite base body forming a conductive circuit when a voltage is applied to the first electrode and the second electrode.

2. The sintering furnace according to claim 1, wherein the furnace shell comprises a first furnace cover, a second furnace cover and a side furnace barrel, the first furnace cover and the second furnace cover are respectively arranged at two ends of the side furnace barrel, and the first furnace cover, the second furnace cover and the side furnace barrel surround to form the cavity.

3. The sintering furnace of claim 1, wherein the first electrode comprises a first graphite electrode and a first metal electrode, the first graphite electrode and the first metal electrode being electrically connected, the first graphite electrode being configured to be connected to a portion of the graphite substrate.

4. The sintering furnace of claim 1, wherein the second electrode comprises a second graphite electrode and a second metal electrode, the second graphite electrode and the second metal electrode being electrically connected, the second graphite electrode being configured to be connected to a portion of the graphite substrate.

5. The sintering furnace according to claim 1, further comprising a heat-insulating chamber disposed in the cavity, wherein a vacuum chamber is formed inside the heat-insulating chamber, the heat-insulating chamber further comprises an air inlet and an air outlet communicated with the vacuum chamber, wherein the graphite substrate to be sintered is disposed in the vacuum chamber, and the first electrode and the second electrode are connected to a portion of the graphite substrate through the heat-insulating chamber.

6. A method for preparing a tantalum carbide coating on the surface of a graphite substrate, which is implemented on the basis of the sintering furnace of any one of claims 1 to 5, and comprises the following steps:

placing the graphite substrate coated with the tantalum carbide turbid liquid in the sintering furnace;

communicating one side, which is not coated with the tantalum carbide turbid liquid, of the graphite matrix with the first electrode and the second electrode respectively;

applying a voltage to the first electrode and the second electrode to cause the first electrode, the second electrode, and the graphite matrix to form a circuit.

7. The method for preparing the tantalum carbide coating on the surface of the graphite substrate according to claim 6, wherein the sintering furnace further comprises a heat preservation cavity, the heat preservation cavity is arranged in the cavity, a vacuum chamber is arranged in the heat preservation cavity, and an air inlet and an air outlet which are communicated with the vacuum chamber are arranged in the heat preservation cavity, the step of placing the graphite substrate coated with the tantalum carbide suspension in the sintering furnace comprises the steps of,

and placing the graphite matrix coated with the tantalum carbide turbid liquid in the vacuum chamber, and enabling the vacuum chamber to be in a vacuum state.

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