CN113737271A - Heating device and crystal pulling equipment - Google Patents

Abstract

The invention discloses a heating device and crystal pulling equipment, relates to the technical field of crystal pulling, and aims to accurately control the temperature in the crystal pulling process under the condition of improving the crystal pulling heating speed. The heating device comprises a microwave generator, a microwave oscillator and a crucible piece. The number of microwave generators is at least one. At least one microwave generator is arranged on the furnace body. The microwave oscillator is arranged in the furnace body. Each microwave generator is in cooperation with a microwave oscillator. The crucible member is provided in a microwave oscillator. The microwave oscillator has a plurality of wave feeding holes for feeding the microwaves generated by the microwave generator to the outer wall of the crucible member. The crucible member is used to convert microwave energy into heat energy. The crystal pulling equipment comprises the heating device provided by the technical scheme. The heating device provided by the invention is used for pulling crystal.

Description

Heating device and crystal pulling equipment

Technical Field

The invention relates to the technical field of crystal pulling, in particular to a heating device and crystal pulling equipment.

Background

The Czochralski method, also known as the Czochralski method, is a method of single crystal growth established from Czochralski (CZ), referred to as the CZ method for short. At present, a single crystal furnace is widely adopted as single crystal growth equipment, and a silicon single crystal rod is grown by a Czochralski method.

In the prior art, a single crystal furnace is provided with a furnace body, a graphite resistance heater arranged in the furnace body and a quartz crucible used for containing crystal materials. The quartz crucible is located in the graphite resistance heater. When the crystal material is heated, large current is introduced into the graphite resistance heater so as to heat the quartz crucible containing the crystal material by using the graphite resistance heater, thereby providing enough heat for the growth of the crystal. At this time, the heat provided by the graphite resistance heater can compensate the heat loss caused by the reduction of the ambient temperature, so that the growth of the single crystal silicon rod is carried out under the relative heat balance condition. However, the heating method has large heat loss, not only is the heating speed slow and the temperature control precision difficult to control, but also is not beneficial to the development of the single crystal manufacturing towards the direction of large size and large thermal field, and cannot meet the technical development requirement of the single crystal manufacturing in the photovoltaic industry.

Disclosure of Invention

The invention aims to provide a heating device and a crystal pulling equipment, which can accurately control the temperature in the crystal pulling process under the condition of improving the crystal pulling heating speed.

In a first aspect, the present invention provides a heating device. The heating device is applied to crystal pulling equipment. The crystal pulling apparatus has a furnace body. The heating device provided by the invention comprises: comprises a microwave generator, a microwave oscillator and a crucible piece. The number of the microwave generators is at least one. At least one microwave generator is arranged on the furnace wall of the furnace body. The microwave oscillator is arranged in the furnace body. The crucible member is provided in a microwave oscillator. Each microwave generator is in cooperation with the microwave oscillator. The microwave oscillator has a plurality of wave feeding holes for feeding the microwaves generated by the microwave generator to the outer wall of the crucible member. The crucible member is used to convert microwave energy into heat energy.

When the technical scheme is adopted, at least one microwave generator is arranged on the wall of the furnace body, the microwave oscillators are arranged in the furnace body, and each microwave generator is matched with the microwave oscillator, so that all microwaves generated by each microwave generator in the crystal pulling process can be received by the microwave oscillators. On the basis, the microwave oscillator is provided with a plurality of wave feeding holes, and the crucible piece is arranged in the microwave oscillator, so that the microwave oscillator is provided with a plurality of wave feeding holes which can feed the microwaves generated by the microwave generator to the outer wall of the crucible piece. Therefore, in the crystal pulling process, the energy source of the crucible piece is introduced into the environment of the crucible piece in a microwave mode, so that the crucible piece is in a microwave field, the microwaves serving as the energy source are converted into heat energy at the crucible piece in the whole process, and no heat energy conversion exists in other areas, therefore, the crucible piece can convert all the microwave energy generated by each microwave generator into heat energy, basically no heat loss exists, and the crucible piece can be ensured to provide sufficient heat for heating crystal materials so as to improve the crystal pulling heating speed.

In addition, in the heating device provided by the invention, the control parameters of the microwave generator can be set so as to accurately control the microwave energy of the microwave field at the crucible piece. The microwave energy of the microwave field and the heat converted by the crucible have interdependence relation, so the heating device provided by the invention can accurately regulate and control the crystal pulling heating temperature.

In one possible implementation, the microwave oscillator includes a ring structure having a hollow cavity. The outer side wall of the ring structure is close to the microwave generator. The inner side wall of the ring structure is close to the crucible piece. The crucible member is disposed within the annular ring region of the annular structure. Each microwave generator is communicated with the hollow cavity. A plurality of wave feed holes are formed in the inner side wall of the annular structure. A plurality of wave feed holes are communicated with the hollow cavity.

Under the condition of adopting the technical scheme, each microwave generator is communicated with the hollow cavity, so that microwaves generated by each microwave generator can enter the hollow cavity, then the microwaves are emitted into the ring-in area of the ring-shaped structure from the hollow cavity by taking the plurality of wave feeding holes as outlets, the microwave field is arranged in the ring-in area, the crucible piece can be ensured to be positioned in the microwave field, and the microwave energy of the microwave field can be completely converted into heat energy by the crucible piece to heat the crystal material.

In a possible implementation mode, the wave feeding areas formed by the wave feeding holes on the outer wall of the crucible piece (the wave feeding area formed by each wave feeding hole on the outer wall of the crucible piece is defined as the crucible wave feeding area of the wave feeding hole) are uniformly distributed.

Under the condition of adopting the technical scheme, the microwave fed to the outer wall of the crucible piece by the plurality of wave feeding holes can surround the outer wall of the crucible piece, so that the heat converted by the crucible piece is uniformly distributed on the crucible piece. At the moment, the crucible piece is used for uniformly heating the crystal material, so that the crystal material can be uniformly melted. And when the crucible piece uniformly heats the crystal material, if the control parameter of the microwave generator is set, the crystal pulling temperature can be more accurately controlled.

In a possible implementation mode, the wave feeding areas formed by the wave feeding holes on the outer wall of the crucible piece are different, and the wave feeding areas formed by two adjacent wave feeding holes on the outer wall of the crucible piece are in contour joint.

By adopting the technical scheme, the crucible wave feeding areas of the two adjacent wave feeding holes are not spaced greatly on the outer wall of the crucible piece and are not overlapped, so that the microwave energy density of the outer wall of the crucible piece is uniform, and the local over-low or over-high microwave energy density of the outer wall of the crucible piece is avoided, thereby ensuring that the heat converted by the crucible piece is uniformly distributed in each area of the crucible piece.

In addition, in the crystal pulling process, when the crucible piece rotates at a preset speed, the outer wall of the crucible piece can also uniformly receive the wave feeding holes from the wave feeding holes, so that heat is further uniformly transferred to the inner crucible, and the uniformity and accuracy of heating the crystal material are improved.

In one possible implementation, the wall thickness of the annular structure is 100mm to 150 mm.

Under the condition of adopting the technical scheme, when the wall thickness of the annular structure is 100 mm-150 mm, the distance between the inner side wall of the annular structure and the outer wall of the crucible piece is not too small. At the moment, the microwaves generated by the microwave generators are transmitted in the hollow cavity along the radial direction of the annular structure, so that the area of the crucible wave feeding area of each wave feeding hole is not too small. At the moment, the crucible wave feeding areas of the wave feeding holes are easy to be jointed together, so that the problem that the local temperature of the crucible piece is too low is solved after the crucible piece converts microwave energy into heat, and therefore when the wall thickness of the annular structure is 100-150 mm, the heat converted by the crucible piece can further uniformly heat the crystal material.

In addition, when the wall thickness of the ring-shaped structure is 100mm to 150mm, the distance between the inner side wall of the ring-shaped structure and the outer wall of the crucible member is not too large. At the moment, the microwaves generated by each microwave generator are transmitted in the hollow cavity along the radial direction of the annular structure, so that the areas of the crucible wave feeding areas of the wave feeding holes are not too large, the crucible wave feeding areas of the wave feeding holes are not overlapped and are easy to joint together, and the problem that the local temperature is too high is solved when the crucible piece converts the microwave energy into heat. Meanwhile, when the area of the crucible wave feeding area of each wave feeding hole is not too large, the microwave energy density of the crucible wave feeding area of each wave feeding hole is higher, so that the heat quantity which can be converted by the crucible piece is higher, and the problem that the heating speed of the crystal material is low due to the fact that the microwave energy density is too low is solved.

In a possible implementation mode, the distance between the axes of two adjacent wave feed holes is 5 mm-10 mm.

Under the condition of adopting the technical scheme, when the distance between the axes of the two adjacent wave feeding holes is 5 mm-10 mm, the distance between the two adjacent wave feeding holes is not too large, so that microwaves generated by each microwave generator can enter each wave feeding hole as much as possible, the reflection times of the microwaves entering the hollow cavity in the hollow cavity are reduced, and the unnecessary microwave energy attenuation is reduced. In addition, when the axial distance between two adjacent wave feeding holes is 5-10 mm, the distance between the two adjacent wave feeding holes cannot be too small, so that the overlapping probability of the crucible wave feeding areas of the two adjacent wave feeding holes on the outer wall of the crucible piece is reduced, the problem of overhigh local temperature of the crucible piece is avoided, and the heating uniformity and accuracy of the crystal material are improved.

In a possible implementation manner, the aperture of at least one wave feed hole is 5 mm-10 mm.

Under the condition of adopting the technical scheme, the microwaves generated by each microwave generator are transmitted to the crucible wave feeding areas of each wave feeding hole through each wave feeding hole according to specific paths, so that the crucible piece can controllably convert the microwave energy into required heat according to the design requirement, the temperature of each area of the crucible piece is ensured to be uniform, and the heating uniformity and accuracy of the crystal material are improved.

In a possible implementation manner, the plurality of wave feeding holes are uniformly arranged on the inner side wall of the annular structure.

Under the condition of adopting the technical scheme, the plurality of wave feeding holes are uniformly arranged on the inner side wall of the annular structure, so that the plurality of wave feeding holes can uniformly feed the microwaves generated by each microwave generator to the outer wall of the crucible piece, and the crucible wave feeding areas of the wave feeding holes are uniformly distributed on the side wall of the crucible piece. On the basis, the microwave can be uniformly fed to the outer wall of the crucible piece by each wave feeding hole according to a preset path, so that the microwave utilization rate is improved, and the crystal material converted by the crucible piece can be uniformly heated.

In a possible implementation, the outer sidewall of the annular structure has at least one via hole communicating with the hollow cavity. The heating device also comprises wave guide tubes connected with the microwave generators. The waveguide is communicated with the hollow cavity through at least one through hole.

By adopting the technical scheme, the conduction pipe can provide closed microwave transmission for each microwave generator, and each conduction hole can accurately guide the microwaves generated by the corresponding microwave generator into the hollow cavity. Based on this, the conduction pipe can be airtight for the microwave channel that each microwave generator provided for the microwave that microwave generator produced can be as much as possible get into in the cavity, thereby reduces unnecessary microwave loss, improves the utilization ratio of the microwave that microwave generator produced.

In one possible implementation, the waveguide may be a metal tube, a corrugated tube, or the like, but is not limited thereto.

In one possible implementation, each via hole corresponds to one wave feed hole, and each via hole is coaxial with the corresponding wave feed hole.

Under the condition of adopting the technical scheme, the distance between each through hole and the corresponding wave feed hole is equal to the width of the hollow cavity, so that the microwave can penetrate through the hollow cavity with the minimum transmission distance. Based on this, when the microwave generated by each microwave generator enters the hollow cavity by taking the corresponding through hole as an inlet, the microwave can penetrate through the hollow cavity to reach the corresponding wave feeding hole in a short time and is emitted into the ring-inside area of the ring-shaped structure through the corresponding wave feeding hole. At the moment, the via hole can not only improve the microwave wave feeding speed corresponding to the wave feeding hole, but also reduce the reflection times of the microwave in the hollow cavity, thereby reducing the unnecessary microwave energy loss.

In one possible implementation, the shape of the at least one wave feed hole is circular, elliptical, polygonal, or irregular.

In a possible implementation manner, the microwave oscillator is made of a microwave reflecting material. The microwave oscillator is made of one or more of molybdenum and stainless steel.

Adopt under the condition of above-mentioned technical scheme, when the microwave that each microwave generator produced was led into the position that does not have the wave feed hole on the microwave oscillator, can be reflected by microwave oscillator, make the microwave only can feed the wave to crucible spare outer wall through the wave feed hole that wherein offers, consequently, when microwave oscillator's material was the microwave reflection material, microwave oscillator can feed the microwave to crucible spare outer wall according to predetermineeing the route, make microwave oscillator can be more accurate control crucible spare heat size and the heat distribution that converts, thereby guarantee the accuracy of crucible spare to the heating of crystal material.

In one possible implementation, the crucible member includes an outer crucible and an inner crucible both provided in the microwave oscillator. The inner crucible is disposed within the outer crucible. The outer crucible is a crucible absorbing waves in a resistance loss mode. The material of the outer crucible is one or more of silicon carbide, zirconia and graphite.

Under the condition of adopting the technical scheme, the polar molecules in the outer crucible are polarized under the action of the microwave field, and generate alternating orientation along with the change of the polarity of the microwave field. In this process, polar molecules in the outer crucible frequently rub to generate heat, causing the outer crucible to convert microwave energy into heat. And because the inner crucible is arranged in the outer crucible, when the inner crucible is used for containing the crystal material, the outer crucible can transfer heat to the inner crucible in a heat transfer mode so as to uniformly and accurately heat the crystal material in the inner crucible.

In a second aspect, the invention also provides a crystal pulling apparatus. The crystal puller comprises the heating device of the first aspect or any one of the possible implementations of the first aspect.

In one possible implementation, the heating device further comprises a heat insulator between the microwave oscillator and the crucible member. The heat insulator is made of wave-transparent material.

By adopting the technical scheme, after the microwaves generated by each microwave generator are fed through each wave feeding hole, the microwaves can reach the outer wall of the crucible piece through the heat insulation body without loss, so that the crucible piece can convert the microwave energy into heat for heating the crystal material. Meanwhile, the heat preservation body is positioned between the microwave oscillator and the crucible piece, so that the crucible piece is preserved by the heat preservation body to reduce the heat loss converted by the crucible piece, and the heat converted by the crucible piece is basically used for heating the crystal material.

In one possible implementation, the heat insulator includes a heat insulating felt and a heat insulating cylinder both provided in the microwave oscillator. The heat preservation felt is arranged on the outer wall of the heat preservation cylinder.

When the heat insulation body is made of wave-transparent material, the heat insulation cylinder and the heat insulation felt are made of strong wave-transparent material. For example: the material of the heat preservation felt can comprise one or more of ceramic fiber felt, zirconia felt, carbon fiber felt and solidified felt. The heat preservation cylinder can be made of carbon-carbon composite materials.

Advantageous effects of the crystal pulling apparatus provided by the second aspect or any of the possible implementations of the second aspect may be obtained with reference to the heating device described in the first aspect or any of the possible implementations of the first aspect.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic structural view of a crystal puller according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a heating apparatus used in a crystal pulling apparatus according to an embodiment of the present invention;

FIG. 3 is a schematic view of another embodiment of a heating apparatus of the present invention in use in a crystal pulling apparatus;

fig. 4 is a schematic structural diagram of a microwave oscillator according to an embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise. The meaning of "a number" is one or more unless specifically limited otherwise.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

The embodiment of the invention provides a crystal pulling device, and FIG. 1 shows a first structural schematic diagram of the crystal pulling device provided by the embodiment of the invention. As shown in FIG. 1, an embodiment of the invention provides a crystal puller that includes a heating device. The heating device heats the crystal material based on the microwave heating principle. Taking semiconductor crystal materials as an example, the crystal materials can be semiconductor crystal materials such as silicon materials, germanium materials and the like, intrinsic semiconductor crystal materials and impurity semiconductor crystal materials doped by heteroatoms.

As shown in FIG. 1, the crystal pulling apparatus may further include a furnace body 11, a pulling head (not shown in FIG. 1), a crucible lifting and rotating mechanism 12, a furnace cover (not shown in FIG. 1), and the like. The heating device is arranged in the furnace body 11 (e.g. the bottom of the furnace body). The bottom of the furnace body 11 may be provided with an exhaust port 13 for discharging impurities in the furnace body 11. The furnace cover can be provided with a peephole. The observation window can observe the internal condition of the furnace body 11.

As shown in FIG. 1, the crystal pulling apparatus may further include a temperature sensor disposed on the lid for monitoring the temperature within the single crystal furnace. When the temperature in the furnace body 11 changes, the temperature data can be fed back to an observation window interface in the single crystal furnace at any time, and the temperature in the crystal pulling process can be monitored in real time.

As shown in FIG. 1, the crystal puller may also include insulation 14 within the furnace to reduce unnecessary heat loss. Since the heating device heats the crystal material based on the microwave heating principle, the material of the thermal insulator 14 is a wave-transparent material. In this case, the heat insulator 14 is a wave-transparent heat insulator. In this regard, when the insulation 14 is disposed within or integrated with a heating apparatus, the insulation 14 does not block and lose microwave energy, such that microwave energy is not substantially lost from the insulation 14 during heating of the crystal by the microwaves. On the basis, the heat preservation body 14 can also reduce the heat loss provided by the heating device, ensure that the heat provided by the heating device can be almost completely used for heating the crystal material, avoid unnecessary heat loss and improve the heating speed of the crystal material.

Illustratively, as shown in FIG. 1, the insulation 14 includes insulation felt 141 and insulation can 142. The heat insulation felt 141 is provided on the outer wall of the heat insulation cylinder 142. It should be understood that when the insulation 14 is made of a wave-transmitting material, the insulation felt 141 and the insulation cylinder 142 are also made of a wave-transmitting material. At this time, the heat loss of the crystal material supplied from the heating device can be prevented by the heat-insulating felt 141 and the heat-insulating cylinder 142 without interfering with the microwave heating of the crystal material.

For example: as shown in fig. 1, the material of the wave-transparent thermal insulation felt 141 may include one or more of a ceramic fiber felt, a zirconia felt, a carbon fiber felt, and a cured felt. Another example is: the material of the heat-insulating cylinder 142 may be a carbon-carbon composite material or other strong wave-transparent material. It should be understood that when the material of the heat preservation felt 141 includes several of ceramic fiber felt, zirconia felt, carbon fiber felt, and solidified felt, the heat preservation felt 141 can be a multi-layer wave-transparent heat preservation felt formed by ceramic fiber felt and zirconia felt, and can also be a heat preservation felt containing ceramic fiber and zirconia.

As shown in fig. 1, taking the growth of single crystal silicon as an example, a silicon material as a seed crystal 21 is put into a heating apparatus, and the silicon material is heated by microwaves under the heat-retaining action of a heat-retaining body 14, so that the silicon material is melted into a silicon melt (melting temperature is about 1420 ℃). After the temperature of the silicon melt is stable, seed crystal silicon is immersed into the silicon melt by using a pulling head, then under the control of an industrial personal computer and under the condition of accurately regulating and controlling the temperature, a crucible lifting and rotating mechanism 12 is matched with the pulling head, and the lower end of the seed crystal silicon is controlled to sequentially undergo crystal growth processes of seeding, shouldering, shoulder rotating, equal-diameter growth, ending and the like, so that the required silicon single crystal rod 22 is grown.

The embodiment of the invention provides a heating device which can realize the heating of various crystal materials by adopting a microwave heating mode. As shown in FIG. 1, the heating device is applied to the crystal pulling apparatus described above. The crystal puller here has, but is not limited to, the furnace body 11 described above. Based on this, the heating device provided by the embodiment of the present invention includes a microwave generator 31, a microwave oscillator 32, and a crucible member 33.

As shown in fig. 1, the number of the microwave generators 31 is at least one, and each microwave generator is provided on the wall of the furnace body 11. For example: a mounting hole is formed in the wall of the furnace body 11, and the microwave generator 31 is mounted on the mounting hole so that the microwave generator 31 is disposed on the wall of the furnace body 11 through the mounting hole. At this time, the microwave output port of the microwave generator 31 is located inside the furnace body 11.

As shown in fig. 1, when the number of the microwave generators 31 is plural, the respective microwave generators 31 may be integrated together or may be provided separately. FIG. 2 shows a schematic diagram of a heating device of the present invention in a crystal pulling apparatus. FIG. 3 shows another schematic diagram of a heating apparatus according to an embodiment of the invention applied to a crystal pulling apparatus. As shown in fig. 2 and 3, the microwave output port of each microwave generator 31 may be disposed around the wall of the furnace body 11, so as to ensure that each microwave generator 31 uniformly supplies microwaves into the furnace body 11.

As shown in fig. 1, the microwave generator 31 includes a dc power supply and a microwave tube electrically connected to the dc power supply. The direct current power supply can convert alternating current electric energy into direct current electric energy and provide the direct current electric energy to the microwave tube, and the microwave tube can convert the direct current electric energy into electric energy of a microwave frequency band and emit the electric energy in a microwave mode. The microwave frequency band can be a frequency band of an electromagnetic spectrum between 300 gigahertz and 300 gigahertz, and can also be a microwave frequency band customized by a person skilled in the art.

The microwave tube may be a microwave transistor, a microwave tube, or the like, but is not limited thereto. The microwave tube can be applied to the fields of measurement and communication, and the output power of the microwave tube is relatively low, so that the microwave tube is suitable for various application scenes. As for the microwave transistor, the microwave transistor may be a microwave low noise transistor, a microwave high power transistor, or the like, but is not limited thereto. As for the output power of the microwave transistor, it can be selected according to the application scenario. For example: in the field of measurement and communication, the output power of the microwave transistor is small. As the microwave electron tube, a magnetron, a klystron, a traveling wave tube, and the like are commonly used, but not limited thereto.

In the embodiment of the present invention, the microwave tube is a magnetron. The magnetron has the advantages of simple structure, high efficiency, low working voltage, simple power supply and strong quartz load change capability, and the converted microwave energy is suitable for microwave heating so as to effectively control the crystal pulling heating temperature.

As shown in fig. 1, the microwave oscillator 32 is provided in the furnace body 11. The crucible member 33 is provided in the microwave oscillator 32 such that the crucible member 33 is located in the furnace body 11. The crucible member 33 may be used to convert microwave energy into heat energy.

As shown in fig. 1, each microwave generator 31 is fitted with a microwave oscillator 32 so that each microwave generator 31 can supply microwaves to the microwave oscillator 32. The microwave oscillator 32 has a plurality of wave feeding holes 321 for feeding the microwaves generated by the microwave generator 31 to the outer wall of the crucible member 33. It should be understood that the shape of the at least one wave feeding hole 321 may be a circle, an ellipse, a polygon or an irregular shape, but is not limited thereto as long as the microwave wave feeding function can be achieved. The shape of each wave feed hole 321 may be the same, partially the same or completely different. But anyway.

As shown in fig. 1, the crucible member 33 has various structures as long as it can convert microwave energy into heat. For example, the following steps are carried out: the crucible member 33 includes an outer crucible 331 and an inner crucible 332 provided in the microwave oscillator 32. The inner crucible 332 is disposed within the outer crucible 331. At this time, both the outer crucible 331 and the inner crucible 332 are in the furnace body 11.

As shown in fig. 1, the outer crucible 331 may be a crucible that absorbs waves in a resistive loss manner in order to convert microwave energy into heat for heating the crystal 21. At this time, the polar molecules in the outer crucible 331 are polarized by the microwave field and alternate orientation is generated as the polarity of the microwave field changes. In this process, polar molecules in the outer crucible 331 frequently rub to generate heat, thereby causing the outer crucible 331 to convert microwave energy into heat. On the basis of the above, the heat converted by the outer crucible 331 can be transferred to the inner crucible 332 in the form of heat transfer to heat the crystal 21 held by the inner crucible.

As shown in fig. 1, the material of the outer crucible 331 may include one or more of silicon carbide, zirconia, and graphite. For example: when the outer crucible 331 is made of graphite, the outer crucible 331 has high microwave energy conversion efficiency, thereby reducing unnecessary microwave energy waste. The inner crucible 332 may be a common crucible. For example: the inner crucible 332 is a quartz crucible or the like, but is not limited thereto.

As shown in fig. 1 to 3, when the heating apparatus according to the present invention is applied to a crystal pulling apparatus, the microwave generator 31, the microwave oscillator 32, the outer crucible 331 and the inner crucible 332 are disposed in the furnace body 11 along a distribution from the outside to the inside, and therefore, the microwaves generated by the microwave generator 31 propagate in a closed environment. Furthermore, the outer crucible 331 and the inner crucible 332 can be provided with the above-mentioned crucible lifting and rotating mechanism 12 to ensure that the crystal pulling apparatus can pull crystals normally. The shapes of the outer crucible 331 and the inner crucible 332 can be selected according to the actual situation. For example: the outer crucible 331 may be a sleeve-like structure that is fitted over the sidewall of the inner crucible 332, such that the crucible lifting and rotating mechanism 12 is used to support the outer crucible 331 and the inner crucible 332 and control the lifting and rotating of the crucible member 33 formed by the outer crucible 331 and the inner crucible 332.

As shown in fig. 1, taking a silicon crystal material as an example, it is possible to place the silicon crystal material in the inner crucible 332 and then activate each of the microwave generators 31 so that the microwaves generated by each of the microwave generators 31 are fed to the microwave oscillator 32. The plurality of wave feeding holes 321 may feed the microwaves generated by the microwave generator 31 to the outer wall of the outer crucible 331 so that the outer crucible 331 is within the microwave field. On this basis, the polar molecules contained in the outer crucible 331 are polarized by the microwave. When the polarity of the microwaves generated by the microwave generators 31 regularly changes, the orientation direction of the polarized polar molecules contained in the outer crucible 331 also changes alternately. In doing so, frequent frictional losses of numerous polar molecules occur within the outer crucible 331, causing the microwave energy (which may also be referred to as electromagnetic energy) to be converted into thermal layers. The outer crucible 331 transfers heat to the inner crucible 332 by means of heat transfer, and heats the silicon crystal material in the inner crucible 332 to gradually melt the silicon crystal material.

As shown in FIG. 1, it can be understood from the above-described structure and application of the heating apparatus that at least one microwave generator 31 is provided on the furnace body 11 and a microwave oscillator 32 is provided inside the furnace body 11, each microwave generator 31 is cooperated with the microwave oscillator 32 so that all the microwaves generated by each microwave generator 31 during the crystal pulling can be received by the microwave oscillator 32. On this basis, since the microwave oscillator 32 has a plurality of wave feeding holes 321 and the outer crucible 331 is provided in the microwave oscillator 32, the plurality of wave feeding holes 321 of the microwave oscillator 32 can feed the microwaves generated by the microwave generator 31 to the outer wall of the outer crucible 331. It can be seen that the energy source of the outer crucible 331 is introduced into the environment of the outer crucible 331 in the form of microwaves during the crystal pulling process, so that the outer crucible 331 is located in the microwave field, the microwaves as the energy source are converted into heat energy at the outer crucible 331 during the whole process, and no heat energy conversion exists in other areas, so that the outer crucible 331 can convert all the microwave energy generated by each microwave generator 31 into heat energy, and basically no heat loss exists, thereby ensuring that the outer crucible 331 can provide sufficient heat to the inner crucible 332 arranged therein to increase the crystal pulling heating rate.

In addition, as shown in fig. 1, in the heating apparatus provided by the embodiment of the present invention, the control parameters of the microwave generator 31 may be set to accurately control the microwave energy of the microwave field in which the outer crucible 331 is located. The microwave energy of the microwave field and the heat converted by the outer crucible 331 have interdependence relation, so the heating device provided by the embodiment of the invention can accurately regulate and control the crystal pulling heating temperature.

As a possible realization, when the crystal pulling apparatus described above comprises an insulation 14, as shown in FIG. 1, the insulation 14 is located between the microwave oscillator 32 and the crucible member 33. When the crucible member 33 comprises the outer crucible 331 and the inner crucible 332, the heat insulator 14 is located between the microwave oscillator 32 and the outer crucible 331, and the inner crucible is disposed inside the outer crucible 332. When the heat retaining body 14 includes the heat retaining felt 141 and the heat retaining cylinder 142, the heat retaining felt 141 is provided on the outer wall of the heat retaining cylinder 142 such that the heat retaining felt 141 is located between the microwave oscillator 32 and the heat retaining cylinder 142. Accordingly, when the heating apparatus of the present invention is applied to a crystal pulling apparatus, the microwave generator 31, the microwave oscillator 32, the heat insulating felt 141, the heat insulating cylinder 142, the outer crucible 331 and the inner crucible 332 are disposed in the furnace body 11 along a distribution from the outside to the inside.

In practical applications, as shown in fig. 1, since the heat insulating body 14 is made of a wave-transparent material, after the microwave generated by each microwave generator is fed through each wave-feeding hole 321, the microwave can reach the outer wall of the crucible member 33 through the heat insulating body without loss, so that the crucible member 33 can convert the microwave energy into heat to heat the crystal material. Meanwhile, due to the heat retaining body 14, the crucible member 33 is retained by the heat retaining body 14 to reduce the heat loss converted by the crucible member 33, so that the heat converted by the crucible member 33 is basically used for heating the crystal material.

As one possible implementation, as shown in fig. 1, the microwave oscillator 32 is made of a microwave reflecting material. When the microwave generated by the microwave generator 31 is not provided with the feeding hole 321 on the microwave oscillator 32, the microwave is reflected by the microwave oscillator 32, so that the microwave can only feed the wave to the outer wall of the crucible piece 33 through the feeding hole 321 provided therein, therefore, when the microwave oscillator 32 is made of a microwave reflecting material, the microwave oscillator 32 can feed the microwave to the outer wall of the crucible piece 33 according to a preset path, so that the microwave oscillator 32 can more accurately control the heat quantity and the heat quantity distribution converted by the crucible piece 33, and the accuracy of the crucible piece 33 for heating the crystal 21 is ensured.

As shown in fig. 1, the microwave reflective material may include one or more of molybdenum and stainless steel. The microwave generator 31 made of a metal material is less likely to deform at a high temperature, and has high stability. Therefore, when the heating device provided by the embodiment of the invention is applied to a crystal pulling device, the microwave oscillator 32 has a low probability of deformation at a high temperature and has good structural stability, so that the microwaves generated by each microwave generator 31 can be accurately fed to the outer wall of the outer crucible 331 according to a preset path through the plurality of wave feeding holes 321, and the accuracy of the crystal pulling temperature is further improved.

In an alternative, as shown in fig. 1 and 4, the microwave oscillator 32 described above includes a ring structure 320 having a hollow cavity. When the microwave oscillator 32 is made of a microwave reflective material, the annular structure 320 may be made of a microwave reflective material such as molybdenum or stainless steel. The ring structure 320 is a ring structure 320 in a broad sense, and includes, but is not limited to, a circular ring structure, an elliptical ring structure, a square ring structure, a multiple ring structure, a special-shaped ring structure, and the like.

As shown in fig. 1 and 4, the outer side wall of the ring structure 320 is close to the microwave generator 31. The inner side wall of the ring structure 320 is adjacent to the crucible member 33. The area enclosed by the inner sidewall of the ring structure 320 is the inner ring area of the ring structure 320. The crucible member 33 is disposed in the ring-shaped region of the ring-shaped structure 320. A plurality of wave feed holes 321 are opened on the inner side wall of the ring structure 320. Each microwave generator 31 communicates with a hollow cavity. The plurality of wave feed holes 321 are all communicated with the hollow cavity. At this time, the microwaves generated by each of the microwave generators 31 enter the hollow cavity, and then are emitted from the hollow cavity into the in-ring region of the ring structure 320 with the plurality of feed holes 321 as outlets, so that the in-ring region of the ring structure 320 has a microwave field. On the basis, when the crucible member 33 is disposed in the ring-shaped region of the ring-shaped structure 320, the crucible member 33 is ensured to be in the microwave field, so that the crucible member 33 can convert all the microwave energy in the microwave field into heat energy for heating the crystal 21. For example, as shown in fig. 1, when the crucible member 23 includes an outer crucible 331 and an inner crucible 332, the outer crucible 331 can convert all of the microwave energy in the microwave field into heat energy, and the heat energy is transferred to the inner crucible 332 containing the crystal material 21 to heat the crystal material 21.

In an alternative, as shown in fig. 1 and 4, the outer sidewall of the ring structure 320 has at least one through hole 322 communicating with the hollow cavity. The heating device further comprises a waveguide 34 connected to each microwave generator 31. The waveguide 34 communicates with the hollow cavity through at least one via 322. It is to be understood that the waveguide 34 may be a metal tube, a corrugated tube, etc., but is not limited thereto. The connection means may be a sealing connection or other connection means.

In practical applications, as shown in fig. 1 and 4, the conducting tube 34 can provide a closed microwave transmission channel for each microwave generator 31, and each conducting hole 322 can accurately guide the microwave generated by the corresponding microwave generator 31 into the hollow cavity. Based on this, the conduction pipe 34 can seal the microwave channels provided by the microwave generators 31, so that the microwaves generated by the microwave generators 31 can enter the hollow cavity as much as possible, thereby reducing unnecessary microwave loss and improving the utilization rate of the microwaves generated by the microwave generators 31.

In one example, as shown in fig. 1 and 4, each via hole 322 corresponds to one wave feed hole 321, so that when the number of via holes 322 is multiple, the wave feed holes 321 corresponding to the via holes 322 are different. Each via hole 322 is coaxial with the corresponding wave feed hole 321. Each wave feeding hole 321 and each via hole 322 are communicated with the hollow cavity, so that the via holes 322 and the corresponding wave feeding holes 321 are communicated with each other. Based on this, the distance between each via hole and the corresponding wave feed hole is equal to the width of the hollow cavity, so that the microwave can pass through the hollow cavity with the minimum transmission distance. In this case, when the microwaves generated by each of the microwave generators 31 enter the hollow cavity through the corresponding through hole 322, the microwaves may pass through the hollow cavity to reach the corresponding wave feeding hole 321 in a short time and are injected into the annular inner region of the annular structure through the corresponding wave feeding hole 321. At this time, the via hole 322 not only can increase the microwave feeding speed corresponding to the wave feeding hole 321, but also can reduce the reflection times of the microwave in the hollow cavity, thereby reducing unnecessary microwave energy loss.

In addition, as shown in fig. 1 and 4, when the microwaves enter the hollow cavity from the via holes 322, a large portion of the microwaves enter the hollow cavity and rapidly enter the ring-inside region of the ring-shaped structure 320 from the corresponding wave feeding holes 321, and a small portion of the microwaves enter the hollow cavity, but do not enter the ring-inside region of the ring-shaped structure 320 from the corresponding wave feeding holes 321, but are reflected by the inner wall of the hollow cavity to the wave feeding holes 321 corresponding to the other via holes 322, and then enter the ring-inside region of the ring-shaped structure 320 together with the microwaves from the other via holes 322. Therefore, the ring structure 320 has a hollow cavity communicated with the plurality of through holes 322, and it can be ensured that the microwave entering the hollow cavity from one of the through holes 322 can be sufficiently fed to the outer wall of the crucible member 33, thereby reducing unnecessary microwave energy loss and improving microwave utilization rate.

In practical applications, the number of the through holes 322 may be the same as or different from that of the microwave generators 31. When the number of the via holes 322 is the same as the number of the microwave generators 31, the microwave output port of each microwave generator 31 may be aligned with a corresponding one of the via holes 322, so that the via holes may rapidly guide microwaves into the hollow cavity. When the number of via holes 322 is different from the number of microwave generators 31, for example: the number of the through holes 322 is smaller than the number of the microwave generators 31, and at least two microwave output ports of the microwave generators 31 can share one through hole 322. That is, each via hole 322 corresponds to two microwave generators 31.

For example: as shown in fig. 1 and 4, when the number of the via holes 322 on the outer sidewall of the ring structure 320 is smaller than the number of the wave feeding holes 321 on the inner sidewall of the ring structure 320, the via holes 322 are uniformly disposed on the outer sidewall of the ring structure 320, and the via holes 322 may be disposed on the outer sidewall of the ring structure 320 in a 2 row × 2 column manner.

As shown in fig. 1 and 4, when the number of the via holes 322 on the outer sidewall of the ring structure 320 is the same as the number of the wave feeding holes 321 on the inner sidewall of the ring structure 320, if a plurality of wave feeding holes 321 are circumferentially disposed on the inner sidewall of the ring structure 320, a plurality of via holes 322 on the outer sidewall of the ring structure 320 are circumferentially disposed on the inner sidewall of the ring structure 320. At this time, the microwaves generated by the respective microwave generators 31 can enter the hollow cavity from various directions, and can be rapidly injected into the in-ring region of the ring structure 320 from the wave feeding holes 321, thereby reducing unnecessary microwave energy loss.

In practical applications, the number of the through holes 322 may be the same as or different from that of the microwave generators 31. When the number of the via holes 322 is the same as the number of the microwave generators 31, the microwave output port of each microwave generator 31 may be aligned with a corresponding one of the via holes 322, so that the via holes may rapidly guide microwaves into the hollow cavity. When the number of via holes 322 is different from the number of microwave generators 31, for example: the number of the through holes 322 is smaller than the number of the microwave generators 31, and at least two microwave output ports of the microwave generators 31 can share one through hole 322. That is, each via hole 322 corresponds to two microwave generators 31. For example: fig. 2 shows 3 microwave generators, each of which may share two columns of vias 322. Another example is: fig. 3 shows 6 microwave generators, each of which may share a column of vias 322.

As shown in fig. 1 and 4, when the number of the via holes 322 on the outer sidewall of the ring structure 320 is smaller than the number of the wave feeding holes 321 on the inner sidewall of the ring structure 320, the via holes 322 are uniformly disposed on the outer sidewall of the ring structure 320, and the via holes 322 may be disposed on the outer sidewall of the ring structure 320 in a 2 row × 2 column manner.

In one example, as shown in fig. 1 and 4, the waveguide 34 may be designed according to practical situations. For example: when the through holes 322 are distributed in a small area on the outer sidewall of the ring structure 320, the guided wave can be completed by a simple linear waveguide. Another example is: when the distribution area of the via holes 322 on the outer sidewall of the ring structure 320 is relatively large, the simple linear waveguide cannot complete the waveguide, and the port of the waveguide 34 connected to the ring structure 320 needs to be designed so that the port of the waveguide 34 connected to the ring structure 320 can cover the distribution area of each via hole 322.

For example, when the plurality of vias are circumferentially disposed on the outer sidewall of the ring structure, the waveguide connecting port of the ring structure covers all areas of the outer sidewall of the ring structure.

In an alternative, as shown in fig. 1 and 4, in order to ensure that the heat that can be converted by the crucible member 33 is uniformly distributed in each region of the crucible member 33, a plurality of wave feeding holes 321 are uniformly distributed in the wave feeding region formed in the outer wall of the crucible member 33. For example, when the crucible member 33 comprises the outer crucible 331 and the inner crucible 321, the heat converted by the outer crucible 321 is uniformly distributed in each region of the outer crucible 331, so that the outer crucible 331 can be transferred to each region of the inner crucible 332 in a heat transfer manner, so that the crystal 21 held in the inner crucible 332 is uniformly heated, and the uniform melting of the crystal 21 and the accuracy of the crystal pulling temperature are ensured.

As shown in fig. 1 and 4, the wave feeding region formed by the wave feeding hole 321 on the outer wall of the crucible member 33 refers to a region where the microwave generated by each microwave generator 31 is guided from the wave feeding hole 321 to the inner region of the ring structure 320, and the microwave corresponding to the wave feeding hole 321 covers the outer wall of the crucible member 33. For convenience of the following description, a wave feeding region formed by each wave feeding hole 321 on the outer wall of the crucible member 33 is defined as a crucible wave feeding region of the wave feeding hole 321. In order to ensure that the microwaves can be fed by the plurality of wave feeding holes 321 according to a designed route, so that the crucible wave feeding areas of the plurality of wave feeding holes 321 are uniformly distributed on the outer wall of the crucible member 33, the microwave feeding holes 321, the ring structure 320 and the like can be designed in various aspects.

In one example, as shown in fig. 1 and 4, the plurality of wave feeding holes 321 are uniformly disposed on the inner sidewall of the ring structure 320. At this time, the plurality of wave feeding holes 321 are circumferentially provided on the inner sidewall of the ring structure 320 with the central axis of the microwave oscillator 32 as the center, so that the plurality of wave feeding holes 321 can uniformly feed the microwaves generated by the respective microwave generators 31 to the outer wall of the crucible member 33, and thus, the crucible wave feeding areas of the respective wave feeding holes 31 are uniformly distributed on the outer wall of the crucible member 33. On the basis, the microwaves can be uniformly fed to the outer wall of the crucible part 33 through the wave feeding holes 321 according to a preset path, so that the utilization rate of the microwaves is improved, and the crystal 21 can be uniformly heated by the heat converted by the crucible part 33.

In one example, as shown in fig. 1 and 4, when the plurality of wave feeding holes 321 may be disposed on the inner sidewall of the ring structure 320 in a surrounding manner, the plurality of wave feeding holes 321 may include 7 layers of wave feeding holes 321. Each layer of wave feeding holes 321 includes a plurality of wave feeding holes 321, and the wave feeding holes are uniformly and circumferentially arranged on the inner side wall of the ring structure 320. The wave feeding holes 321 in two adjacent layers may be arranged on the inner side wall of the ring structure 320 in a staggered manner or an aligned manner.

As shown in fig. 1 and 4, when two adjacent wave feeding holes 321 are arranged on the inner side wall of the ring structure 320 in a staggered manner, the geometric centers of the two wave feeding holes 321 are staggered. When two adjacent layers of wave feeding holes 321 are arranged on the inner side wall of the ring structure 320 in an aligned manner, a plurality of wave feeding holes 321 are arranged on the inner side wall of the ring structure 320 in the manner shown in fig. 4.

As shown in fig. 1 and 4, when the number of the via holes 322 on the outer sidewall of the ring structure 320 is the same as the number of the wave feeding holes 321 on the inner sidewall of the ring structure 320, the via holes 322 on the outer sidewall of the ring structure 320 are circumferentially disposed on the inner sidewall of the ring structure 320. At this time, the microwaves generated by the respective microwave generators 31 can enter the hollow cavity from various directions, and can be rapidly injected into the in-ring region of the ring structure 320 from the wave feeding holes 321, thereby reducing unnecessary microwave energy loss.

In one example, as shown in fig. 1, in order to improve the heating uniformity of the crystal 21, when the crucible wave feeding areas of the plurality of wave feeding holes 321 are uniformly distributed on the outer wall of the crucible member 33, the wave feeding areas formed on the outer wall of the crucible member 33 by the respective wave feeding holes 321 are different, and the wave feeding areas formed on the outer wall of the crucible member 33 by the adjacent two wave feeding holes 321 are in contour joint. At this time, the crucible wave feeding regions of two adjacent wave feeding holes 321 do not have a large interval on the outer wall of the crucible member 33, and do not overlap.

As shown in fig. 1 and 4, when the crucible wave feeding areas of two adjacent wave feeding holes 321 are not spaced apart from each other at a larger distance from the outer wall of the crucible member 33, the crucible member 33 does not have a position where the microwave energy density is too low, so that the probability that the heat converted by the crucible member 33 is locally too low on the crucible member 33 can be reduced, and the melting speed and uniformity of the crystal 21 can be effectively improved. When the crucible wave feeding areas of two adjacent wave feeding holes 321 are not overlapped on the outer wall of the crucible piece 33, the position of the outer wall of the crucible piece 33 with too high microwave energy density cannot appear, the probability that the heat converted by the crucible piece 33 is locally too high on the crucible piece 33 can be reduced, and therefore the melting speed and uniformity of the crystal 21 are effectively improved.

Therefore, as shown in fig. 1, the heating device provided by the present invention can effectively ensure that the heat converted by the crucible member 33 is uniformly distributed in each region of the crucible member 33, thereby improving the melting speed and heating uniformity of the crystal material. In addition, when the crucible piece 33 rotates at a preset speed in the crystal pulling process, the outer wall of the crucible piece 33 can uniformly receive the wave fed from each wave feeding hole 321, so that the microwave is uniformly converted into heat, and the crystal material is uniformly and accurately heated.

In some examples, as shown in fig. 1 and 4, the thickness of the microwave oscillator 32 (i.e., the thickness of the annular structure 320) is mainly determined by the size of the furnace space of the furnace body 11 and the size of the mounting hole formed in the wall of the furnace body 11. For example: when the ratio of the installation holes formed in the wall of the furnace body 11 is large, the microwave generators 31 can emit microwaves in a large number of areas. At this time, by designing the thickness of the microwave oscillator 32, it is possible to supply microwave of sufficient energy to the crucible member 33 and to ensure that the crucible wave feeding region of the wave feeding hole 321 is uniformly distributed on the outer wall of the crucible member 33. Another example is: when the furnace space of the furnace body 11 is relatively small, the thickness of the microwave oscillator 32 is not necessarily too large.

For example, as shown in fig. 1 and 4, if the thickness of the ring structure 320 is too large, the distance between the inner wall of the ring structure 320 and the crucible member 33 is relatively small, resulting in a relatively small area of the wave feeding region formed by each wave feeding hole 321 on the outer wall of the crucible member 33. At this time, the profiles of the crucible wave feeding regions of the wave feeding holes 321 are difficult to join together on the outer wall of the crucible member 33, so that after the crucible member 33 converts the microwave energy into heat, the crucible member 33 has a problem of too low local temperature, which is not favorable for uniformly heating the crystal material 21 and increasing the heating speed of the crystal material 21.

As shown in fig. 1 and 4, it is proved by experiments that the wall thickness of the ring-shaped structure 320 is less than or equal to 150 mm. At this time, the distance between the inner side wall of the ring structure 320 and the outer wall of the crucible member 33 is not too small. The microwave generated by the microwave generator 31 propagates in the hollow cavity along the radial direction of the ring-shaped structure 320, so that the area of the crucible wave feeding region of each wave feeding hole 321 is not too small, and therefore, the crucible wave feeding regions of each wave feeding hole 321 are easily jointed together, and after the crucible piece 33 converts the microwave energy into heat, the crucible piece 331 is not easy to have the problem of too low local temperature, and the heating uniformity of the crystal material 21 is ensured.

As shown in fig. 1 and 4, if the thickness of the ring-shaped structure 320 is too small, the distance between the inner sidewall of the ring-shaped structure 320 and the crucible member 33 is relatively large, which results in overlapping of the crucible wave feeding regions of the wave feeding holes 321 on the outer wall of the crucible member 33, and therefore, after the crucible member 33 converts the microwave energy into heat, the crucible member 33 is prone to have a problem of too high local temperature, which is not favorable for uniformly heating the crystal 21. Tests have shown that the distance between the inner side wall of the ring-shaped structure 320 and the outer wall of the crucible part 33 is not too great when the wall thickness of the ring-shaped structure 320 is between 100mm and 150mm (e.g. 100mm, 150mm, 120mm or 130 mm). At this time, the microwave generated by the microwave generator 31 propagates in the hollow cavity along the radial direction of the ring structure 320, so that the area of the wave feeding region of each wave feeding hole 321 is not too large, and therefore, the crucible wave feeding regions of each wave feeding hole 321 are not overlapped and are easily joined together, and it is ensured that the crucible piece 33 is not prone to have a problem of too high local temperature after the crucible piece 33 converts the microwave energy into heat. Meanwhile, when the crucible wave feeding area of each wave feeding hole 321 is not too large in area, the microwave energy density of the crucible wave feeding area of each wave feeding hole 321 is relatively high. On the basis, the crucible piece 33 can convert relatively high heat, so that the problem of low heating speed of the crystal 21 caused by low microwave energy density is avoided, and the melting speed of the crystal 21 is improved.

For example, as shown in FIGS. 1 and 4, when the crystal pulling heating apparatus further comprises the insulation 14, the microwave energy density in the crucible feeding area of each feeding hole 321 is relatively high, so that the microwave can be fed to the outer wall of the crucible member 33 through the insulation 14, thereby avoiding the problem that the microwave cannot pass through the insulation 14 due to too low microwave energy.

In one example, as shown in fig. 1 and 4, the axial distance between two adjacent wave feed holes 321 is 5mm to 10 mm. The axial distance between two adjacent wave feed holes 321 refers to: the distance between the central axes of two adjacent wave feeding holes 321 along the extending direction of the side wall of the ring structure 320. The central axis of each wave feeding hole 321 refers to a geometric central straight line passing through a cross section of the wave feeding hole 321 along the hole depth direction of the wave feeding hole.

As shown in fig. 1 and 4, when the inner sidewall of the annular structure 320 has the same number of wave feeding holes 321 as the outer sidewall of the annular structure 320 has the same number of through holes 322, and the through holes 322 are coaxial with the corresponding wave feeding holes 321, if the axial distance between two adjacent wave feeding holes 321 is 5mm to 10mm, two through holes 322 corresponding to two adjacent wave feeding holes 321 are adjacent, and the axial distance between two adjacent through holes 322 is also 5mm to 10mm,

as shown in fig. 1 and 4, when the axial distance between two adjacent wave feeding holes 321 is 5mm to 10mm, the distance between two adjacent wave feeding holes 321 is not too large, so that the microwaves generated by the microwave generator 31 can enter each wave feeding hole 321 as much as possible, and the reflection times of the microwaves entering the hollow cavity in the hollow cavity are reduced, thereby reducing unnecessary microwave energy attenuation, improving the utilization rate of the microwaves, and promoting the heating speed of the crystal material 21. In addition, when the axial distance between two adjacent wave feed holes 321 is 5 mm-10 mm, the distance between two adjacent wave feed holes 321 is not too small, so that the overlapping probability of the crucible wave feed areas of the two adjacent wave feed holes 321 on the outer wall of the crucible piece 33 is reduced, the problem of too high local temperature of the crucible piece 33 is avoided, and the heating uniformity and accuracy of the crystal material 21 are improved.

In one example, as shown in fig. 1 and 4, the aperture of the at least one wave feed hole is 5mm to 10 mm. The aperture is a broad aperture and refers to the largest dimension in the cross-section of the wave feed hole. For example: for a circular feed hole, the aperture is the diameter of the circular cross section of the circular feed hole. For a square feed hole, the aperture is the length of the diagonal of the square cross section of the square feed hole.

As shown in fig. 1 and 4, when the microwaves generated by the microwave generator 31 are transmitted to the crucible wave feeding areas of the respective wave feeding holes through the respective wave feeding holes according to specific paths, the crucible member 33 can controllably convert the microwave energy into heat at a desired temperature according to design requirements, and the temperature of each area of the crucible member 33 is ensured to be uniform. For example, when the crucible member 33 comprises the outer crucible 331 and the inner crucible 332, the outer crucible 331 transfers heat to the inner crucible 332 located in the outer crucible 331 so as to controllably heat the crystal material 21 contained in the inner crucible 332, thereby improving the uniformity and accuracy of heating the crystal material 21.

As shown in fig. 1 to 4, when the wave feeding holes 321 and the via holes 322 are the same in number and the via holes 322 are coaxial with the corresponding wave feeding holes 321, if the size of the via holes 322 is the same as that of the wave feeding holes 321, when the plurality of wave feeding holes 321 are circumferentially arranged on the inner side wall of the annular structure 320, the plurality of via holes 322 correspond to the plurality of wave feeding holes 321 one by one. And, the wave feeding holes are distributed on the inner side wall of the ring structure 320, and the plurality of via holes 322 are circumferentially disposed on the outer side wall of the ring structure 320. At this time, the microwave can uniformly and rapidly pass through the hollow cavity through the via hole 322, so that the microwave energy density of the crucible wave feeding area of each wave feeding hole 321 is close to that of the crucible piece 33, thereby improving the uniformity of the microwave wave feeding to the crucible piece 33.

As can be seen from fig. 1 and 4, the thickness of the ring-shaped structure 320, the aperture of the wave feeding hole 321, and the axial distance between two adjacent wave feeding holes 321 have a relatively important effect on microwave heating. Based on the foregoing disclosure, those skilled in the art can adjust and combine the ranges of these parameters, and design the uniformity and energy density of the microwave field in which the crucible 33 is located to accurately convert the heat energy meeting the requirement of the crystal pulling temperature, so that the crucible 33 can heat the crystal 21 uniformly and effectively, and the heating efficiency of the crystal 21 is improved.

In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims (10)

1. A heating device for use in a crystal puller having a furnace body, the heating device comprising:

at least one microwave generator arranged on the furnace wall of the furnace body;

the microwave oscillators are arranged in the furnace body, and each microwave generator is matched with each microwave oscillator;

a crucible member for converting microwave energy into heat energy, the crucible member being provided within the microwave oscillator; the microwave oscillator is provided with a plurality of wave feeding holes for feeding the microwaves generated by the microwave generator to the outer wall of the crucible piece.

2. The heating device of claim 1, wherein the microwave oscillator comprises a ring structure having a hollow cavity, an inner sidewall of the ring structure being adjacent to the crucible member, an outer sidewall of the ring structure being adjacent to the microwave generator, the crucible member being disposed within an inner annular region of the ring structure; wherein the content of the first and second substances,

every microwave generator with the cavity intercommunication, it is a plurality of the wave feed hole is seted up in the inside wall of annular structure, it is a plurality of the wave feed hole with the cavity intercommunication.

3. The heating apparatus as claimed in claim 2, wherein the plurality of wave feed holes are uniformly distributed in a wave feed region formed in an outer wall of the crucible member.

4. The heating device as claimed in claim 2, wherein each wave feed hole is different in a wave feed area formed on the outer wall of the crucible member, and the wave feed areas formed on the outer wall of the crucible member by two adjacent wave feed holes are in contour joint; wherein the content of the first and second substances,

the wall thickness of the annular structure is 100 mm-150 mm; and/or the presence of a gas in the gas,

the axial distance between two adjacent wave feed holes is 5-10 mm; and/or the presence of a gas in the gas,

the aperture of at least one wave feed hole is 5 mm-10 mm.

5. The heating device of claim 2, wherein the plurality of wave feed holes are uniformly arranged on the inner side wall of the annular structure.

6. The heating device of claim 2, wherein the outer sidewall of the ring structure has at least one via in communication with the hollow cavity, the heating device further comprising a waveguide connected to each of the microwave generators, the waveguide being in communication with the hollow cavity through the at least one via.

7. The heating device of claim 6, wherein each of said via holes corresponds to one of said wave feed holes, and each of said via holes is coaxial with the corresponding wave feed hole.

8. The heating device according to any one of claims 1 to 7, wherein the microwave oscillator is made of a microwave reflecting material, and the microwave reflecting material comprises one or more of molybdenum and stainless steel; and/or the presence of a gas in the gas,

the crucible piece comprises an outer crucible and an inner crucible which are both arranged in the microwave oscillator, and the inner crucible is arranged in the outer crucible; the outer crucible is a crucible absorbing waves in a resistance loss mode; the outer crucible is made of one or more of silicon carbide, zirconia and graphite.

9. A crystal puller comprising a heating device as claimed in any one of claims 1 to 8.

10. A crystal puller as set forth in claim 9 further comprising insulation between the microwave oscillator and the crucible member, the insulation being of wave transparent material; wherein the content of the first and second substances,

the heat preservation body is including all establishing heat preservation felt and a heat preservation section of thick bamboo in the microwave oscillator, the heat preservation felt is established the outer wall of a heat preservation section of thick bamboo, the heat preservation felt is located microwave oscillator with between the heat preservation section of thick bamboo.

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