Heating device and heating disc

Abstract

The invention provides a heating disc and a heating device. The heating disc comprises a heating wire layer and a heat pipe layer, and the heating wire layer and the heat pipe layer are distributed in a layered mode. The heat pipe layer is provided with heat pipes which are arranged according to a first rule and have self-uniform temperature, the heat pipes comprise working liquid, and the working liquid conducts heat transfer through phase change. And the heating wire layer is provided with heating wires which are arranged according to a second rule.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor device manufacturing, and in particular to a heating disc. BACKGROUND

[0002] The heating disc is a key component directly contacting with a wafer in a thin film deposition process, and provides a suitable process environment temperature for the thin film deposition by itself heating. In the thin film deposition process, the uniformity of the temperature field has a significant impact on the process effect, and the uniformity of the temperature field will usually affect the consistency of the thin film quality on the wafer.

[0003] At present, the heating form of the heating disc is divided into single-zone heating and multi-zone heating. The single-zone heating has the problem of uneven overall heating. The multi-zone heating can make up for this shortcoming. The multi-zone heating is divided into single-temperature-point and multi-temperature-point. The single-temperature-point multi-zone heating method can only control the current, and the actual temperature cannot be monitored. The multi-temperature-point multi-zone heating method has better temperature control effect, but the multi-zone heating has the problem of multi-temperature field coupling, and the control is difficult, and there is time delay in control, and the temperature cannot be quickly and uniformly and stably realized, and the cost is high and the processing difficulty is great.

[0004] At the same time, the heating disc is easy to produce various forms of deformation in the process of heating to high temperature. The deformation of the disc surface under the high temperature state is difficult to detect, and the deformation will seriously affect the effect of the thin film process. SUMMARY

[0005] In order to overcome the defects of the prior art, the present application provides a heat self-uniform heating disc and a heating device, which realizes self-regulation of the temperature between the regions of the heating disc, and strengthens the inherent rigidity of the disc body of the heating disc.

[0006] The heating disc of the present application comprises a heating wire layer and a heat pipe layer.

[0007] The heating wire layer and the heat pipe layer are distributed in layers.

[0008] The heat pipe layer has heat pipes with self-uniform temperature arranged according to a first rule, and the heat pipes comprise working liquid, and the working liquid performs heat transfer through phase change.

[0009] The heating wire layer has heating wires arranged according to a second rule.

[0010] In one embodiment, the heat pipe layer is located above the heating wire layer, and the first rule is different from the second rule.

[0011] In one embodiment, the first rule is that the heat pipes are arranged in a radial manner from the center of the heating disc.

[0012] In one embodiment, the first rule is that the heat pipes comprise a plurality of circumferential heat pipes with different radii and a plurality of radial heat pipes arranged in a radial pattern from the center of the heating disc.

[0013] Of course, those skilled in the art should understand that the heat pipes can comprise only radial or only circumferential heat pipes.

[0014] In one embodiment, the heat pipe layer is in a high-thermal-conductivity capillary structure.

[0015] In one embodiment, the second rule is that the heating wires comprise a plurality of circumferential heating wires and transition heating wires connecting adjacent circumferential heating wires.

[0016] In one embodiment, the transition heating wires can be radial straight or arc heating wires.

[0017] In one embodiment, the heating wires can be symmetric double-end heating wires or mosquito coil vortex single-end heating wires.

[0018] In one embodiment, the heating wires can be single-zone or divided into multiple zones.

[0019] In one embodiment, the heat pipes in a first zone of the heat pipe layer have a first working fluid, and the heat pipes in a second zone of the heat pipe layer have a second working fluid, which can be different or the same.

[0020] In one embodiment, the material of the heat pipes is selected from copper, stainless steel, aluminum, or non-metallic materials.

[0021] In one embodiment, the pressure, liquid filling rate, or composition of the working fluid in the heat pipes is adjustable.

[0022] In one embodiment, the working fluid comprises at least one or more of thermally conductive grease, mercury, cesium, sodium, potassium, and sulfur.

[0023] The present application also provides a heating device comprising a heating disc as described above and a heating disc handle. The heating disc handle is connected to the heating disc.

[0024] The heating disc handle has a heating electrode coupled to the heating wire layer. The heating electrode passes through the heating disc handle and is connected to the heating wire layer in the heating disc as a whole. The heating electrode comprises a positive electrode and a negative electrode coupled to a power supply.

[0025] The heating device of the present application realizes the self-regulation of the temperature between the regions of the heating disc, and the high-thermal-conductivity capillary structure of the heating disc can improve the temperature uniformity of the heating disc, the temperature feedback rate of the heating disc, and the overall structural rigidity of the heating disc. In particular, the high-thermal-conductivity capillary structure of the self-uniform temperature can directly perform thermal conduction regulation without temperature acquisition and feedback control of the temperature measuring device, thereby greatly enhancing the temperature regulation rate of the disc body. BRIEF DESCRIPTION OF DRAWINGS

[0026] The above summary of the application and the following detailed description of the application will be better understood when read in conjunction with the accompanying drawings. It should be noted that the drawings are merely examples of the claimed application. In the drawings, like reference numerals refer to like or similar elements.

[0027] Figure 1 A side view of a heating device according to an embodiment of the present application is shown;

[0028] Figure 2 A side view of a heating device according to an embodiment of the present application is shown;

[0029] Figure 3 A schematic diagram of a heating device according to an embodiment of the present application is shown;

[0030] Figure 4 A top view of a heating device according to an embodiment of the present application is shown;

[0031] Figure 5A A schematic diagram of a heat pipe arrangement according to an embodiment of the present application is shown;

[0032] Figure 5B A schematic diagram of a heat pipe arrangement according to an embodiment of the present application is shown;

[0033] Figure 5C A schematic diagram of a heat pipe arrangement according to an embodiment of the present application is shown;

[0034] Figure 6 A working schematic diagram of a heat pipe according to an embodiment of the present application is shown;

[0035] Figure 7A A surface temperature simulation diagram of a heating disc with a first heat pipe structure according to an embodiment of the present application is shown, wherein the temperature difference range is 4.5 degrees;

[0036] Figure 7B A surface temperature simulation diagram of a heating disc with a second heat pipe structure according to an embodiment of the present application is shown, wherein the temperature difference range is 4.5 degrees;

[0037] Figure 7C A surface temperature simulation diagram of a heating disc without a heat pipe structure according to an embodiment of the present application is shown, wherein the temperature difference range is 14 degrees;

[0038] Figure 8A A heating wire temperature simulation diagram of a heating disc with a first heat pipe structure according to an embodiment of the present application is shown, wherein the heating wire temperature difference range is 10 degrees;

[0039] Figure 8B A heating wire temperature simulation diagram of a heating disc with a second heat pipe structure according to an embodiment of the present application is shown, wherein the heating wire temperature difference range is 10 degrees;

[0040] Figure 8C A heating wire temperature simulation diagram of a heating disc without a heat pipe structure according to an embodiment of the present application is shown, wherein the heating wire temperature difference range is 17.04 degrees;

[0041] Figure 9A A whole cross-section temperature simulation diagram of a heating disc with a first heat pipe structure according to an embodiment of the present application is shown;

[0042] Figure 9B A whole cross-section temperature simulation diagram of a heating disc with a second heat pipe structure according to an embodiment of the present application is shown;

[0043] Figure 9C A heating wire temperature simulation diagram of a heating disc without a heat pipe structure according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0044] The detailed features and advantages of the present application are described in detail in the following detailed description, which is sufficient for any person skilled in the art to understand the technical content of the present application and to implement it, and according to the description, claims and drawings disclosed in the specification, a person skilled in the art can easily understand the related purposes and advantages of the present application. Although the description of the present application will be introduced in combination with the preferred embodiments, it does not mean that the features of the present application are limited to the embodiments. On the contrary, the purpose of introducing the application in combination with the embodiments is to cover other options or modifications that can be extended based on the claims of the present application. In order to provide a deep understanding of the present application, many specific details will be included in the following description. The present application can also be implemented without using these details. In addition, in order to avoid confusion or obscure the focus of the present application, some specific details will be omitted in the description.

[0045] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0046] In addition, the terms "upper", "lower", "left", "right", "top", "bottom", "horizontal", "vertical" as used in the description and the appended drawings are made with reference to the orientation of the figures in which the description is presented. Such relative terms are used for convenience of description only and are not intended to limit the application to any particular orientation of the device or its use.

[0047] It will be understood that, although the terms "first", "second", "third", etc. can be used herein to describe various elements, channels, components, regions, layers and / or sections, these elements, channels, components, regions, layers and / or sections should not be limited by these terms as these terms are only used to distinguish one element, channel, component, region, layer and / or section from another element, channel, component, region, layer and / or section. Also, the terms "first", "second", "third", etc. are only used to describe different elements, channels, components, regions, layers and / or sections and do not imply a relative importance of the different elements, channels, components, regions, layers and / or sections.

[0048] As used in this application and the appended claims, the terms "a", "an" and / or "the" include both singular and plural referents unless the context clearly dictates otherwise. The terms "comprising", "having", "including" and "containing" are to be construed as open-ended terms (i.e., meaning "including, but not limited to") unless otherwise noted.

[0049] Some embodiments use numerical descriptors of ingredients, attributes, quantities. It should be understood that such numerical descriptors used in the description of embodiments are, in some examples, modified by the words "about", "approximately", or "generally". Unless otherwise stated, "about", "approximately" or "generally" indicates that the number can vary by ±20%. Accordingly, numerical values used in the specification and claims of this application are approximations which can vary depending on the desired properties sought to be obtained in a particular embodiment. In some embodiments, numerical values should be considered in the context of the number of significant figures used in the description and the general number base used in the art. Although the numerical ranges and parameters setting forth the broadest scope of the application in some embodiments are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values set forth in the specific examples are provided to be as precise as practicable.

[0050] Also, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. The terms "comprises", "comprising", "includes", "including", and the like can be used herein and are intended to encompass the elements and / or steps listed thereafter, as well as other elements and / or steps. At least one embodiment is further defined by a set of claims following the detailed description.

[0051] Figure 1 and Figure 2 A side view of a heating device according to an embodiment of the present application is shown. The heating device of the present application comprises a heating disc 101 and a heating disc handle 102, wherein the heating disc handle 102 is located below the heating disc 101 and supports the heating disc 101. The heating disc 101 comprises a heating wire layer 103 and a heat pipe layer 104. The heating disc handle 102 has a heating electrode 105 coupled with the heating wire layer 103.

[0052] The heating disc 101 can transfer heat to the wafer by one or more of heat conduction, heat radiation and heat convection.

[0053] In one embodiment, the heat pipe layer 104 is located above the heating wire layer 103.

[0054] In one embodiment, the heating electrode 105 passes through the heating disc handle 102 from bottom to top and is integrated with the heating wire layer 103 in the heating disc 101. The heating electrode 105 generally comprises a positive electrode and a negative electrode coupled with a power supply.

[0055] Figure 3 A schematic diagram of a heating device according to an embodiment of the present application is shown. Figure 4 A top view of a heating device according to an embodiment of the present application is shown.

[0056] In combination Figure 3 and Figure 4 , the present application provides a self-homogeneous heating device. The heating device comprises a heating disc and a heating disc handle connected with the heating disc. Generally, the heating disc is disc-shaped and the heating disc handle is a cylindrical handle extending from the body of the heating disc.

[0057] The material of the heating device can be metal or ceramic, etc.

[0058] The heating disc is implanted with a heating wire layer and a heat pipe layer inside.

[0059] The heating wire layer comprises heating wires 301 arranged in a regular pattern.

[0060] In one embodiment, the heating wires 301 comprise a plurality of circumferential heating wires and a plurality of transition heating wires connecting adjacent circumferential heating wires.

[0061] In one embodiment, the transition heating wires can be radial straight or arc heating wires.

[0062] The heating wires 301 are heating components inside the heating disc, generally resistance wires, which generate heat through the Joule effect of electric current; the heat is conducted to the wafer through the heating disc.

[0063] In one embodiment, the heating wire 301 can be arranged as a single-zone heating type.

[0064] In one embodiment, the heating wire 301 can be arranged as a multi-zone heating type. Each zone has a positive cable and a negative cable.

[0065] In one embodiment, the heating wire 301 can be a symmetric double-end heating wire or a mosquito coil vortex single-end heating wire.

[0066] The heating wire layer serves as an energy source, which is not limited to resistance wire heating, but can also be heated or cooled by one or more forms of mica printing heating sheet, water path, oil path, gas path, etc.

[0067] The heat pipe layer and the heating wire layer are arranged in layers, for example, the heat pipe layer can be located above the heating wire layer.

[0068] In one embodiment, the heat pipe layer and the heating wire layer are implanted inside the heating disc body by welding, sintering or one-piece forming, etc.

[0069] The heat pipe layer includes heat pipes 302 arranged in a regular pattern.

[0070] The heat pipe is a self-uniform temperature component that transfers heat through internal working fluid phase change.

[0071] The heat pipe is a high thermal conductivity capillary structure. The high thermal conductivity capillary structure can improve the temperature uniformity of the heating disc, the temperature feedback rate of the heating disc, and increase the overall structural rigidity of the heating disc. In particular, the high thermal conductivity capillary structure with self-uniform temperature can directly adjust the heat conduction without temperature acquisition and feedback control of the temperature measuring device, greatly enhancing the temperature adjustment rate of the disc body.

[0072] In addition, the heat pipe itself is an independent structure and belongs to a non-energy source, which does not require external power supply or additional energy device such as a pump, simplifying the temperature control system, saving space for the heating disc and handle part, and realizing efficient self-temperature regulation while greatly reducing the processing difficulty of the heating disc.

[0073] The heat pipe can be made into various shapes. In one embodiment, the heat pipes 302 are arranged in a radial pattern from the center of the heating disc.

[0074] The heat pipe can also be in the form of a heat spreader, which can be embedded as a part of the heating disc as a whole.

[0075] In one embodiment, the heating device of the present application can further include a temperature measuring device for temperature acquisition, a temperature control device, a support wafer related component, etc. The temperature measuring device can be integrated in the heating disc.

[0076] In one embodiment, the temperature measuring device can be a thermocouple.

[0077] The temperature collected by the temperature measuring device is transmitted to the temperature control device as observation data in the form of signals. The temperature control device makes real-time adjustment to the current input power according to the observed data, including instantaneous temperature, temperature gradient, and change rate of the temperature gradient, to form a closed-loop control.

[0078] Figure 5A A schematic diagram of the arrangement of heat pipes according to an embodiment of the present application is shown. In this embodiment, the heat pipes 302 are arranged in a radial pattern from the center of the heating disc.

[0079] Figure 5B A schematic diagram of the arrangement of heat pipes according to an embodiment of the present application is shown. In this embodiment, the heat pipes 302 include a plurality of circumferential heat pipes with different radii and a plurality of radial heat pipes arranged in a radial pattern from the center of the heating disc. Of course, those skilled in the art will understand that the heat pipes can include only circumferential heat pipes.

[0080] Figure 5C A schematic diagram of the arrangement of heat pipes according to an embodiment of the present application is shown. In this embodiment, the heat pipes 302 are arranged in a radial pattern from the center of the heating disc. Compared to Figure 5A , this arrangement is more dense.

[0081] Figure 6 A schematic diagram of the operation of heat pipes according to an embodiment of the present application is shown.

[0082] The heat pipes of the present application have high thermal conductivity, isothermality, reversible conduction, and thermal diode properties. In addition, the heat transfer capacity under a small temperature difference is stronger than that of ordinary metals.

[0083] In one embodiment, the material of the heat pipes can be selected from copper, stainless steel, aluminum, or non-metallic materials. In a preferred embodiment, the material of the heat pipes can be stainless steel.

[0084] The heat pipes have a working fluid inside. The heat pipes rely on the phase change of the working fluid for heat transfer.

[0085] In one embodiment, the working fluid includes, but is not limited to, one or more of the following: thermal grease, mercury, cesium, sodium, potassium, and sulfur.

[0086] The selection of the working fluid needs to meet the use temperature of the heating disc. To meet a wider range of use temperatures, in one embodiment, heat pipes with different working fluids can be implanted in the heating disc. For example, the heat pipes in a first region of the heat pipe layer have a first working fluid, the heat pipes in a second region of the heat pipe layer have a second working fluid, and the first working fluid and the second working fluid are different.

[0087] In one embodiment, the first working fluid can also be the same as the second working fluid.

[0088] In one embodiment, the pressure in the heat pipe, the liquid filling rate, the working fluid composition, etc. can be adjusted to adapt to specific working conditions.

[0089] Reference Figure 6 The heat pipe of the present application works as follows:

[0090] When heating, the positive and negative electrodes of the heating wire are connected to a power supply, and the heating wire starts to heat up through the Joule effect. The heating wire heats up and transfers heat to the heating plate through heat conduction. The heating plate then transfers heat to the wafer through one or more of heat conduction, heat radiation, and heat convection. During the heating process, the temperature control device applies output power to the heating wire. The temperature is collected by a temperature measuring device, usually a thermocouple. The collected temperature is transmitted to the temperature control device as observation data in the form of a signal. The temperature control device adjusts the input power in real time based on the observed data, including instantaneous temperature, temperature gradient, and rate of change of temperature gradient, to form a closed-loop control.

[0091] When the heating plate reaches the desired set temperature, it also reaches the working temperature range of the heat pipe working fluid. At this time, the temperature field of the heating plate will not be completely uniform. The end with higher temperature will accelerate the evaporation of the working fluid inside the heat pipe. The vaporization of the working fluid will carry away the heat in that area. The evaporated working fluid will flow to the cold end of the heat pipe as saturated steam and condense in the area with lower temperature. The condensation releases the latent heat of vaporization in the steam to the area. The liquefied working fluid enters the capillary structure inside the heat pipe and returns to the other end through capillary force. When the temperature distribution is reversed, the working direction of the heat pipe is also reversed. Through this phase change cycle, the overall temperature field of the heating plate tends to the same temperature.

[0092] To compare the effects of heat pipe structure and no heat pipe structure, the following simulation experiments were conducted. The heating wire power was set to 710w, the target temperature was 400℃, and the heat pipe thermal conductivity was 1e+5W / M.K.

[0093] Figure 7A A heating plate surface temperature simulation diagram with a first heat pipe structure according to an embodiment of the present application is shown, wherein the temperature difference range is 4.5 degrees.

[0094] Figure 7B A heating plate surface temperature simulation diagram with a second heat pipe structure according to an embodiment of the present application is shown, wherein the temperature difference range is 4.5 degrees.

[0095] Figure 7C A heating plate surface temperature simulation diagram without a heat pipe structure according to an embodiment of the present application is shown, wherein the temperature difference range is 14 degrees.

[0096] Figure 8AA heating wire temperature simulation diagram of a heating disc with a first heat pipe structure according to an embodiment of the present application is shown, wherein the heating wire temperature difference range is 10 degrees.

[0097] Figure 8B A heating wire temperature simulation diagram of a heating disc with a second heat pipe structure according to an embodiment of the present application is shown, wherein the heating wire temperature difference range is 10 degrees.

[0098] Figure 8C A heating wire temperature simulation diagram of a heating disc without a heat pipe structure according to an embodiment of the present application is shown, wherein the heating wire temperature difference range is 17.04 degrees.

[0099] Figure 9A A whole cross-section temperature simulation diagram of a heating disc with a first heat pipe structure according to an embodiment of the present application is shown.

[0100] Figure 9B A whole cross-section temperature simulation diagram of a heating disc with a second heat pipe structure according to an embodiment of the present application is shown.

[0101] Figure 9C A whole cross-section temperature simulation diagram of a heating disc without a heat pipe structure according to an embodiment of the present application is shown.

[0102] From the simulation experiment, it can be seen that the heat pipe structure has a better heat conduction effect, and the surface temperature difference of the heating disc is smaller.

[0103] The heating device has the following advantages:

[0104] Firstly, the heating disc improves the temperature uniformity of the heating disc through the high-thermal-conductivity capillary structure. In the traditional heating disc structure, the temperature of the outer side of the heating disc is usually low due to the heat dissipation of the cavity side wall. The high-thermal-conductivity capillary structure reduces the temperature difference between the inner and outer rings of the heating disc on the basis of the single-zone heating disc. The thermal conductivity of the capillary heat pipe can generally reach 5000-100000 W / (m·K), while the thermal conductivity of the aluminum alloy is generally only 240 W / (m·K).

[0105] Secondly, the heating disc structure can improve the temperature feedback rate of the heating disc through the high-thermal-conductivity capillary. When the disc body temperature changes under the action of ventilation or radio frequency, the traditional structure of the heating disc undergoes a closed-loop control cycle of TC sensing-> feedback control system-> heating wire power adjustment-> TC sensing. The capillary heat pipe can effectively reduce the TC sensing time and enhance the disc body temperature adjustment rate through direct heat conduction adjustment.

[0106] Thirdly, the high-temperature-resistant and high-strength capillary tube is used to reinforce the metal disc structure for high-temperature application. The material of the heating disc is usually metal aluminum, which has a large risk of deformation at high temperature (400C). The heating disc of the present application is reinforced by the built-in capillary structure, which improves the anti-deformation ability at high temperature. The capillary heat pipe material can be selected from copper, stainless steel, aluminum or non-metallic materials. For the aluminum heating disc, stainless steel can be used to facilitate the welding of the heating disc (melting point 1400 higher than the melting point of aluminum 650) and improve the overall structural stiffness.

[0107] The terms and expressions employed herein are used as terms of description and exemplification, and are not intended to limit the application to the specific forms or fields described. It is not intended to exclude any equivalents of aspects of the described examples, or any equivalents of the features described (or part thereof). It is recognized that other modifications, changes and substitutions are possible and it is intended to include all such modifications, changes and substitutions as fall within the scope of the appended claims. Other modifications, variations, and alternatives will be apparent to others skilled in the art based on the teachings herein.

[0108] Similarly, it is to be noted that, while the above-described embodiments have been characterized by the use of certain terminology, the use of such terminology is purely for the purpose of simplifying the description of the embodiments disclosed herein and to assist in the understanding of one or more embodiments of the application. The use of such terminology is not intended to imply that the features described are more than the features mentioned in the claims.

[0109] Similarly, it is to be noted that, while the above-described embodiments have been characterized by the use of certain terminology, the use of such terminology is purely for the purpose of simplifying the description of the embodiments disclosed herein and to assist in the understanding of one or more embodiments of the application. The use of such terminology is not intended to imply that the features described are more than the features mentioned in the claims.

Claims

1. A heating plate, characterized in that: include: A heating wire layer and a heat pipe layer, wherein the heating wire layer and the heat pipe layer are distributed in layers; The heat pipe layer comprises heat pipes arranged according to a first rule and having a uniform temperature, wherein the heat pipes comprise a working fluid that transfers heat through phase change; The heating wire layer has heating wires arranged according to a second regularity.

2. The heating plate according to claim 1, wherein The heat pipe layer is located above the heating wire layer, and the first rule is different from the second rule.

3. The heating plate according to claim 1, wherein The first rule is that the heat pipes are arranged radially from the center of the heating plate.

4. The heating plate according to claim 1, wherein The first rule is that the heat pipe includes a plurality of circumferential heat pipes with different radii and a plurality of radial heat pipes arranged radially from the center of the heating plate.

5. The heating plate according to claim 1, wherein The heat pipe layer is a high thermal conductivity capillary structure.

6. The heating plate according to claim 1, wherein The second rule is that the heating wire includes multiple turns of circumferential heating wire and transition heating wires connecting adjacent circumferential heating wires.

7. The heating plate according to claim 1, wherein The heat pipes in the first area of ​​the heat pipe layer contain a first working fluid, and the heat pipes in the second area of ​​the heat pipe layer contain a second working fluid, and the first working fluid and the second working fluid are different.

8. The heating plate according to claim 1, wherein The pressure, filling rate or composition of the working fluid in the heat pipe are adjustable.

9. The heating plate according to claim 1, wherein: The material of the heat pipe is selected from copper, stainless steel, aluminum or non-metallic materials.

10. The heating plate according to claim 1, wherein The working fluid includes at least one or more of thermal conductivity, mercury, cesium, sodium, and potassium.

11. A heating device, characterized in that: A heating tray according to any one of claims 1 to 10, and a heating tray handle; The heating plate handle is connected to the heating plate; The heating plate handle has a heating electrode coupled to the heating wire layer; The heating electrode passes through the heating plate handle and is connected to the heating wire layer in the heating plate as a whole; The heating electrode includes a positive electrode and a negative electrode coupled to a power source.

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