Hot plate structure and processing method thereof

Abstract

The invention discloses a hot plate structure and a processing method thereof. The hot plate structure comprises a sandwich type hot plate, the top layer part of the sandwich type hot plate is provided with a plurality of temperature sensors, the middle layer part of the sandwich type hot plate comprises a heating plate body, and the bottom layer part of the sandwich type hot plate is a base; wherein a circuit system is arranged on the heating disc body, and the middle layer part and the top layer part are integrally connected. The ceramic plate and the aluminum plate body of the top layer part also adopt an integral sintering mode or a welding mode, so that the influence of uncontrollable contact thermal resistance between the mica heating plate or the armored heating wire and the aluminum plate body of the top layer part is avoided, and the performance consistency of the heating plate is improved; the circuit system and the heating disc body are sintered integrally, heat conduction is uniform, and the problems that the efficiency of winding a heating wire on a mica sheet is low and the mica sheet and the heating wire are in poor contact are solved.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor manufacturing, and in particular to a hot plate structure and a processing method thereof. Background Art

[0002] With the development of semiconductor-related technologies, the manufacturing process of semiconductor devices and chips is also developing rapidly. In the manufacturing process of semiconductor devices, a heating plate is usually used to heat the device to be manufactured, and the temperature uniformity of the heating plate is required to be high, such as 150℃±0.3℃, 400℃±1.5℃, etc.

[0003] For example, the "high uniformity wafer heater for reducing wafer ion contamination" disclosed in Chinese patent documents, with application number "CN2023228985121", includes a heating plate, a shell and a stainless steel base plate. The heating plate is composed of an aluminum alloy plate, an upper mica sheet, an electric heating film, a Teflon sheet, a lower mica sheet, a PTFE plate, an upper stainless steel plate and a lower stainless steel plate stacked in sequence. The heating plate is fixed in the shell, and the bottom of the shell is fixed with the stainless steel base plate by long fixing screws; threaded blind holes corresponding to the long fixing screws and blind holes reserved for ceramic temperature sensors are opened on the aluminum alloy plate; positioning through holes reserved for the long fixing screws are opened at the same positions of the upper mica sheet, Teflon sheet, lower mica sheet, PTFE plate and upper stainless steel plate, and the electric heating film avoids the positions of these positioning through holes; in addition to the mounting holes reserved for the long fixing screws, mounting holes are also reserved for the wiring terminals on the lower stainless steel plate.

[0004] As recorded in the above scheme, the current heating plate mostly adopts one of the two methods of mica sheet heating or armored heating wire heating. These two methods require the mica sheet or armored heating wire to be combined with the surface of the heating plate. The assembly adopts screw fastening or gluing, which has high requirements on the flatness of the plate. At the same time, gluing or welding has problems such as air holes, resulting in poor actual temperature uniformity of the heating plate, and the temperature uniformity trend is inconsistent and uncontrollable. Summary of the invention

[0005] In order to overcome the problem of poor temperature uniformity in the current mica sheet heating method and armored heating wire heating method, the present invention provides a heat plate structure and a processing method thereof, which adopts an integrally connected sandwich heat plate to avoid the uncontrollable influence of the contact thermal resistance between the mica heating sheet or armored heating wire and the aluminum plate body on the top layer, thereby improving the performance consistency of the heating plate.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: A hot plate structure includes a sandwich hot plate, wherein a top layer of the sandwich hot plate is provided with a plurality of temperature sensors, a middle layer includes a heating plate body, and a bottom layer is a base; wherein a circuit system is provided on the heating plate body, and the middle layer is integrally connected with the top layer.

[0007] Accurate temperature monitoring and control are achieved through the temperature sensor on the top layer, while the integrated connection between the middle layer heating plate and the top layer provides better thermal conductivity and structural stability. This design not only improves the overall performance of the heating plate, but also simplifies the manufacturing process and improves production efficiency. The uniformity of the heating plate is improved to ensure uniform temperature in different areas; the stability of the heating plate structure is strengthened and the service life is extended; the assembly process is simplified and the production cost is reduced; the thermal efficiency of the heating plate is improved and energy consumption is reduced. In addition, the temperature sensors on the top layer can be flexibly arranged as needed, which increases the flexibility of the design. In addition, by further optimizing the layout of the sensors to achieve more precise temperature control, or exploring new materials to improve the thermal efficiency and durability of the heating plate. At the same time, considering the needs of different application scenarios, the structure of the heating plate can be customized to meet the working requirements in specific environments.

[0008] Preferably, the middle layer includes a ceramic disk and an insulating disk, and the circuit system is arranged between the ceramic disk and the insulating disk, and the ceramic disk is fixedly connected to the top layer. The fixed connection between the ceramic disk and the top layer is achieved by a sintering or welding process, which enhances the stability of the overall structure and provides good insulation performance to ensure safe use. This fixing method ensures the tightness and durability of the structure. Placing the circuit system between the ceramic disk and the insulating disk provides an efficient thermal management and electrical isolation solution, further improving the temperature uniformity and reliability of the heat plate. Through the use of ceramic materials, the heat plate can not only withstand high temperatures, but also provide uniform heat diffusion. At the same time, the precise arrangement of the circuit system between the ceramic and insulating disks avoids the risk of electrical short circuits and ensures the safety and stability of the heat plate under various working conditions.

[0009] Preferably, the ceramic disk is made of alumina ceramic or aluminum nitride ceramic, and is fixedly connected to the top layer by sintering or welding. The ceramic disk can be alumina ceramic or aluminum nitride ceramic, both of which are favored for their excellent thermal conductivity, high mechanical strength and good chemical stability. The ceramic disk is fixedly connected to the top layer by sintering or welding, which not only ensures the stability and reliability of the structure, but also provides an efficient heat conduction path for the entire heat plate.

[0010] Preferably, the circuit system includes a copper circuit layer, which is formed by etching or printing process, and the circuit layout is a spiral line type. The spiral line type layout has a higher heat diffusion efficiency. Compared with the traditional straight line or grid layout, the spiral line type can more effectively utilize the thermal conductivity of the ceramic material to achieve rapid heat transfer. Copper material is selected for its excellent thermal and electrical conductivity, and the application of etching or printing process ensures the precise layout of the circuit and good electrical connection.

[0011] Preferably, the spiral linear circuit layer includes several layers from the inside to the outside, the number of layers is proportional to the size of the disk, and the pitch of each layer is independent. By layering and differentiating the pitch, customized heat transfer solutions can be provided for different areas of the hot disk. The inner layer has a larger pitch because of the small amount of heat concentration and heat exchange with the environment, so faster heat transfer is required, while the outer layer has a smaller pitch because of the large amount of heat exchange with the environment on all sides and more heat distribution is required. This design allows heat to be transferred and distributed more effectively between different layers, thereby improving the temperature uniformity of the entire hot disk.

[0012] Preferably, the spiral linear circuit layer includes several layers with the same pitch, and the width and thickness of the etched lines in each layer are different. By adjusting the width and number of turns of the line, the heat transfer rate can be controlled at different levels. The inner and middle layers have fewer turns because of the small heat accumulation and heat exchange with the environment, while the outer layer has more turns because of the need for more uniform heat distribution. In addition, by adjusting the width of the line, the heat transfer can be optimized without affecting the overall performance of the circuit. By precisely controlling the width and number of turns of the line, more sophisticated heat management is achieved, and higher flexibility is provided for manufacturing.

[0013] The top layer is an aluminum plate, and a number of grooves are provided on the surface of the top layer. By utilizing the high thermal conductivity of aluminum and the specific structure of grooves provided on the surface of the top layer, the surface area of ​​the heat plate can be increased, thereby improving the heat dispersion capability and optimizing the heat conduction path. The groove design not only helps to evenly distribute heat, but also improves the contact between the top layer and other components, avoiding the problem of reduced reliability due to different thermal stresses of different materials.

[0014] The base of the bottom layer is provided with outlet holes and screw holes. By providing the outlet holes and screw holes on the base, the installation and maintenance process of the hot plate can be simplified. The outlet holes allow the electrical lines to be safely led out from the inside of the base, avoiding the risk of damage caused by the lines being exposed to the outside. At the same time, the screw holes provide a standardized interface for connecting the hot plate with other components or equipment, which facilitates rapid assembly and disassembly.

[0015] The present invention also discloses a method for processing the above-mentioned hot plate structure, comprising the following steps: S1: The ceramic discs of the top layer and the middle layer are combined by sintering or welding; S2: Sintering the circuit system on the other side of the ceramic disk; S3: Use laser drilling to open screw holes on the ceramic plate; S4: Assemble the various layers of the disk into an integrated structure by fastening with screws.

[0016] This method consists of several key steps to ensure efficient manufacturing and excellent performance of the heat plate structure. First, the aluminum plate body at the top layer is tightly combined with the ceramic heating plate body in the middle by sintering or welding to form a solid one-piece structure, which not only improves the efficiency of heat conduction and ensures that the heating plate body can evenly transfer heat to the aluminum plate body at the top layer, but also enhances the overall stability. Next, the copper circuit is sintered on the other side of the ceramic plate to form an efficient heating layer, using the excellent electrical and thermal conductivity of copper, and the circuit is precisely laid out through etching or printing processes. Then, laser drilling technology is used to accurately open screw through holes on the ceramic plate, avoiding cracking problems and ensuring the quality and accuracy of the holes. Finally, the aluminum plate body at the top layer, the ceramic heating plate body in the middle, the insulating plate body and the bottom mounting plate body are assembled into a stable overall structure by screws.

[0017] Preferably, the top plate body and the heating plate body are bonded together by DBC eutectic sintering process / DPC direct copper electroplating process / AMB active metal welding process / LAM active metal welding process. In this solution, the processes include DBC (direct copper bonding) eutectic sintering process, DPC (direct copper electroplating) process, AMB (active metal brazing) process and LAM (laser assisted active metal welding) process. The selection of these processes provides flexibility and adaptability for the manufacture of the heating plate to meet different production conditions and performance requirements. Different bonding processes have their own unique advantages, and the most suitable process can be selected according to specific application requirements and manufacturing conditions. For example, the DBC process has high thermal conductivity and good mechanical strength; the DPC process provides a cost-effective and easy-to-implement method; and the AMB and LAM processes are selected because of their excellent performance in bonding high melting point metals.

[0018] This solution has the following beneficial effects: 1) The copper heating circuit can be arranged at will according to the temperature uniformity requirements, without restrictions on shape and is not affected by the bending radius. (2) The heating circuit and the ceramic disk are sintered in one piece, which has uniform heat conduction and avoids the low efficiency of the mica sheet wrapped around the heating wire and the problem of poor contact between the two. (3) The ceramic disk and the aluminum disk body on the top layer are also sintered or welded in one piece to avoid the uncontrollable influence of the contact thermal resistance between the mica heating sheet or the armored heating wire and the aluminum disk body on the top layer, thereby improving the performance consistency of the heating disk. (4) The structure is simple, easy to assemble and produce, and improves manufacturing efficiency. (5) The aluminum disk body on the top layer and the middle ceramic layer and copper heating circuit are an integrated structure with uniform heat conduction and high temperature uniformity. (6) The copper heating circuit can be arranged at will according to the needs to improve the upper limit of the temperature uniformity of the entire heating disk. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the hot plate structure; Figure 2 This is a schematic diagram of the circuit layer routing layout in Example 1; Figure 3 This is a schematic diagram of the circuit layer routing layout in Example 2; Figure 4 This is a schematic diagram of the method of grooving a ceramic disc; Figure 5 It is a schematic diagram of the integrated slotting of the ceramic plate and the top layer; In the figure: 100 sandwich hot plate, 1 top layer, 2 middle layer, 3 bottom layer, 4 circuit system, 41 inner layer, 42 middle layer, 43 outer layer, 5 ceramic plate, 6 insulating plate, 7 groove. DETAILED DESCRIPTION

[0020] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions.

[0021] Example 1 like Figure 1 As shown, in this embodiment, a new heat plate structure is proposed, aiming to improve the temperature uniformity and assembly stability of the heat plate through optimized design. The structure is a sandwich heat plate 100, which is composed of key parts such as an aluminum plate body of a top layer 1, a ceramic plate 5 of a middle layer 2, a copper heating circuit layer 4, an insulating plate 6 and a mounting plate body of a bottom layer 3. The overall principle is to achieve efficient heat conduction and uniform heat distribution based on the material properties and arrangement of each layer.

[0022] The aluminum plate at the top layer is the part that directly contacts the device to be manufactured and has the functions of heat transfer and device support. Aluminum material is selected for its excellent thermal conductivity, ensuring that heat is quickly transferred from the ceramic layer to the top layer, achieving rapid response and effective heat transfer. The surface of the aluminum plate at the top layer is designed with a number of grooves 7, which not only increase the contact area with the device and improve the heat conduction efficiency, but also provide stable support for the device.

[0023] The ceramic layer is located under the aluminum plate body at the top, and is made of high-performance Al2O3HP, Al2O3 containing ZrO2, or AlN materials. These materials have excellent high temperature resistance and good thermal conductivity, which are the key to achieving high temperature uniformity. The combination of the ceramic layer and the copper heating circuit layer adopts a variety of advanced processes, such as DBC eutectic sintering process, DPC direct electroplating copper process, AMB active metal welding process, and LAM active metal welding process. The selection of these processes provides a variety of possibilities for the close combination of the ceramic layer and the copper heating circuit layer, ensuring the stability and durability of the hot plate.

[0024] like Figure 2As shown, the copper heating circuit layer, as a heat source, is designed with a spiral linear layout, which is formed by etching or printing process. This layout not only improves the heat conduction efficiency of the circuit, but also increases the surface area and promotes uniform distribution of heat. Copper material is selected for its excellent electrical and thermal conductivity, ensuring efficient conversion of electrical energy into thermal energy.

[0025] The insulating plate is covered under the copper heating circuit layer. Its material can be ceramic material, mica sheet and other high temperature resistant materials. The main function of the insulating plate is to avoid leakage and ensure safety. At the same time, the existence of the insulating plate also helps the heat transfer in the ceramic layer, further improving the temperature uniformity of the hot plate.

[0026] The mounting plate is the bottom layer of the entire structure, providing the necessary mechanical support and electrical connection. The mounting plate is designed with outlet holes and screw holes for easy assembly and wiring. This design simplifies the assembly process and improves production efficiency.

[0027] The working principle of the entire heat plate structure is that the heat is heated by the copper heating circuit layer, and the heat is transferred to the aluminum plate body on the top layer through the ceramic layer, and finally evenly distributed to the device to be manufactured. The close combination of the ceramic layer and the copper heating circuit layer, as well as the efficient heat conduction of the aluminum plate body on the top layer, together achieve high temperature uniformity of the heat plate. The use of the insulating plate body ensures the safety of the entire structure. The reasonable layout of the installation plate body facilitates rapid assembly and maintenance.

[0028] In this embodiment, efficient heat transfer and excellent temperature uniformity of the hot plate are achieved through innovative design.

[0029] First, the structural design of this embodiment uses ceramic materials as the substrate. Ceramic materials are ideal for manufacturing hot plates due to their excellent thermal conductivity, high temperature resistance and good mechanical strength. In the present invention, high-performance ceramic materials such as Al2O3HP, Al2O3 containing ZrO2 or AlN can be selected. These materials have a low thermal expansion coefficient, can maintain structural stability at high temperatures, and provide an efficient heat conduction path.

[0030] The copper heating circuit layer is another key component of this embodiment. By directly etching the copper heating circuit on the ceramic substrate, higher heat conduction efficiency and better temperature uniformity can be achieved. Compared with the traditional mica sheet heating method, the close combination of the copper heating circuit and the ceramic substrate reduces the contact thermal resistance and improves the heat transfer efficiency. In addition, the copper heating circuit can be flexibly designed according to the actual application requirements, without being restricted by the shape and bending radius, which makes it possible to achieve higher temperature uniformity.

[0031] like Figure 5As shown, in this embodiment, the aluminum plate body of the top layer is tightly combined with the ceramic substrate and the copper heating circuit layer by integrated sintering or welding to form an integral structure. This structural design not only improves the mechanical strength of the heat plate, but also ensures that the heat is evenly transferred in the aluminum plate body of the top layer. The aluminum plate body is a key factor in achieving uniform temperature performance due to its light weight, high thermal conductivity and good processing performance. Through integrated sintering or welding, the bonding force between the aluminum plate body, the ceramic substrate and the copper heating circuit layer is strengthened, avoiding the thermal resistance problem caused by poor contact in traditional heating methods.

[0032] In this embodiment, the improvement of the temperature uniformity of the hot plate is also due to the thermal matching between the copper heating circuit layer and the ceramic substrate. By precisely controlling the thickness and layout of the copper heating circuit layer, the heat can be evenly distributed in the ceramic substrate. This thermal matching design reduces the loss of heat during the transfer process and improves the overall thermal efficiency of the hot plate.

[0033] like Figure 4 As shown, in order to further improve the temperature uniformity of the heat plate, this embodiment also adopts some special designs. For example, grooves or through holes are provided on the ceramic substrate, which can effectively reduce thermal stress and avoid cracking or deformation problems caused by mismatch of thermal expansion coefficients. In addition, by optimizing the shape and size of the copper heating circuit layer, more precise heat regulation can be achieved to meet the needs of different application scenarios. When manufacturing the heat plate of this embodiment, technicians in this field need to consider some process details. For example, the preparation of the ceramic substrate requires precise control of the particle size and sintering conditions of the powder to ensure the uniformity and mechanical strength of the substrate. The etching and printing of the copper heating circuit requires precise control of the width, spacing and thickness of the circuit to achieve the required temperature uniformity. The processing of the aluminum plate body of the top layer and the combination with the ceramic substrate require appropriate welding or sintering technology to ensure the stability of the structure and the thermal conductivity.

[0034] Example 2 like Figure 3 As shown, the heat plate structure in this embodiment is similar to that in Embodiment 1 in many key aspects, but also has its own unique features. Similarly, the structure is composed of an aluminum plate body, a ceramic layer, a copper heating circuit layer, an insulating plate body and a mounting plate body at the top layer, which ensures its basic heat conduction and assembly functions. However, this embodiment adopts a different strategy from Embodiment 1 in the layout design of the copper heating circuit layer.

[0035] In Example 1, the spiral linear layout of the copper heating circuit layer is divided into three layers with different pitches: inner, middle, and outer layers, in order to optimize the distribution of heat. In this embodiment, the spiral linear layout is characterized in that all layers have the same pitch, but the width and thickness of the etched lines vary according to the layers. Specifically, the turn ratio in this embodiment is 2:2:5, the corresponding width ratio is 3:2:1, and the thickness ratio remains at 1:1:1. This design allows the current density and heat distribution at different levels to be controlled by adjusting the width and thickness of the line while maintaining a uniform pitch, thereby achieving more sophisticated heat management.

[0036] The combination of the aluminum disc body and the ceramic layer at the top layer is similar in the two embodiments, and is achieved through sintering or welding. This integrated design not only improves the heat conduction efficiency, but also enhances the stability of the overall structure. The insulating disc body is also made of high-temperature resistant materials, such as ceramics or mica sheets, to ensure electrical safety and assist heat conduction. The design of the mounting disc body is also consistent in the two embodiments, with outlet holes and screw holes for easy assembly and wiring.

[0037] A significant advantage of this embodiment is the design of its copper heating circuit layer, which allows for more flexible adjustment of heat distribution to suit different application requirements. The uniform pitch design simplifies the manufacturing process, while precise control of heat distribution can be achieved by adjusting the width and thickness of the line. This flexibility enables the heat plate structure of this embodiment to better adapt to various complex thermal management requirements.

[0038] Compared with Example 1, this embodiment may provide higher temperature uniformity performance in certain specific applications. For example, in situations where more uniform heat distribution is required, the copper heating circuit layer design of this embodiment can more effectively meet this requirement. However, this design may also bring some challenges, such as the need for more precise control of the width and thickness of the etched line during the manufacturing process.

[0039] Example 3 The heat plate structure of this embodiment further expands the design concept of the present invention, and achieves more efficient heat management and better temperature uniformity through the carefully designed copper circuit layer layout and ceramic layer optimization. The detailed operation process and usage scheme of this embodiment are as follows: First, choose the appropriate ceramic material based on Figure 4 Schematic diagram of the ceramic layer slotting structure. The grooves are opened in different areas on the ceramic sheet. This design can effectively reduce the thermal stress caused by the difference in thermal expansion coefficients between metal and ceramic at high temperatures above 200°C. By dividing the ceramic heating layer into multiple areas, it not only improves the stability of the structure, but also helps to achieve a more uniform temperature distribution. Next, the copper heating circuit layer is designed. According to Figure 2 and Figure 3The circuit layout diagram of the spiral line layout is designed, and the copper circuit of the spiral line layout is divided into three layers: inner, middle and outer. According to the size of the hot plate, such as 8 inches, the pitch and number of turns of each layer are set. In this embodiment, we use Figure 3 The circuit layout shown in the figure, wherein the pitch of the inner layer 41, the middle layer 42 and the outer layer 43 circuits are the same, but the width and thickness of the etched circuits are different, the turn ratio is 2:2:5, the corresponding width ratio is 3:2:1, and the thickness ratio is 1:1:1. This design allows the heat distribution to be optimized by adjusting the width and thickness of the circuit, thereby achieving more refined heat management. Then, the integrated sintering manufacturing process described in the present invention is adopted, and the copper heating circuit layer is manufactured by etching or printing circuit board methods. This integrated sintering process enhances the bonding strength between the ceramic layer and the copper heating circuit layer, improves the upper limit of the temperature uniformity of the heat plate, and achieves a uniformity of within ±1°C at a high temperature of 400°C. During the installation of the aluminum plate body on the top layer, according to Figure 5 As shown in the figure, grooves are opened according to the results of thermal stress analysis to avoid the influence of high temperature thermal stress on the disc body. This design further improves the stability and durability of the disc body. Finally, laser cutting is used to accurately cut the integrated disc body structure, effectively avoiding the problem of ceramic disc body cracking caused by traditional machining methods. The accuracy and efficiency of laser cutting provide guarantees for the entire manufacturing process.

[0040] It is also worth noting that when applying this embodiment, the selection of ceramic materials should be based on the temperature range and thermal expansion coefficient requirements of the actual application to ensure thermal stability and reliability. The design of the copper heating circuit layer should fully consider the uniformity of heat distribution and current density to avoid local overheating or current concentration. The design of the grooves on the ceramic layer and the aluminum plate on the top layer should be based on a detailed thermal stress analysis to ensure the stability and durability of the structure. During the laser cutting process, attention should be paid to controlling the cutting accuracy and speed to avoid damage to the ceramic or copper circuit.

[0041] In addition, different types of ceramic materials, such as Al2O3 or AlN materials containing ZrO2, can be selected according to different application requirements to improve temperature resistance. The design of the copper heating circuit layer can be adjusted according to the actual heat distribution requirements, such as changing the pitch, width and thickness of the circuit. The groove design of the ceramic layer and the aluminum disc on the top layer can be optimized according to the results of thermal stress analysis to improve the stability and durability of the structure.

[0042] This embodiment achieves a more uniform heat distribution and a higher upper limit of temperature uniformity by grooving in different areas and optimizing the design of the copper heating circuit layer, meeting the needs of high-performance manufacturing equipment. The adoption of integrated sintering process and laser cutting technology improves manufacturing accuracy and efficiency and reduces production costs. It can be customized according to different application requirements and is suitable for hot plates of various sizes and shapes. And by opening grooves on the ceramic layer and optimizing the layout of the copper circuit layer, the cracking and deformation problems caused by thermal stress under high temperature are effectively solved, and the temperature uniformity performance of the hot plate is improved. In addition, the application of integrated sintering process and laser cutting technology further improves manufacturing accuracy and efficiency and reduces production costs. It can be customized according to different application requirements and is suitable for hot plates of various sizes and shapes. In addition, the solution also has good adaptability and flexibility to meet the needs of different customers.

[0043] It should be added that the manufacture of the heat plate structure begins with the preparation of the ceramic substrate, which is produced by ceramic powder. This step is crucial because the quality of the ceramic substrate directly affects the mechanical strength and thermal conductivity of the heat plate. In the present invention, the ceramic substrate adopts high-performance Al2O3HP, Al2O3 containing ZrO2 or AlN materials, which have excellent high temperature resistance and thermal conductivity. Subsequently, the ceramic substrate and the copper plate are co-fired at high temperature to form an integrated heating layer. This step is the core of the present invention. Through the co-firing process, the copper heating circuit is tightly combined with the ceramic substrate to form an integrated structure with uniform heat conduction. Compared with the traditional mica sheet winding heating wire, this integrated sintering method not only improves the thermal conductivity efficiency, but also avoids the problem of poor contact. Next, the integrated heating layer is etched and printed, and the circuit layout is designed according to the temperature uniformity requirements. This step allows the circuit to be flexibly arranged according to the specific application requirements, without being restricted by the shape and bending radius. This design improves the upper limit of the temperature uniformity of the heat plate, while also ensuring the overall performance consistency of the heat plate.

[0044] After forming the circuit layout, the integrated heating layer is co-fired and melted with aluminum powder or aluminum liquid, and combined with the aluminum disc body of the top layer to form an integrated structure. This melting and sintering method further strengthens the bonding force between the aluminum disc body of the top layer and the ceramic heating layer, ensuring the stability and durability of the heat disc structure. The multi-layer integrated structure is then punched and slotted. These process steps are to improve the mechanical strength and thermal conductivity of the heat disc. Through precise punching and slotting processes, thermal stress can be effectively controlled to avoid structural damage at high temperatures. Finally, the integrated structure processed by the above process is assembled with the insulating disc body and the mounting disc body by screws. The choice of the insulating disc body can be high-temperature resistant materials such as ceramic materials and mica sheets to ensure electrical safety and thermal conductivity. This assembly method simplifies the production process, improves manufacturing efficiency, and is also convenient for later maintenance and replacement.

[0045] The layout of the copper heating circuit can be flexibly designed according to the temperature uniformity requirements, without being restricted by shape and bending radius. The integrated sintering method avoids the poor contact problem of the traditional mica sheet around the heating wire and improves the thermal conductivity. The integrated sintering or welding method of the aluminum plate body and the ceramic heating layer on the top layer improves the performance consistency of the heating plate and avoids the influence of uncontrollable contact thermal resistance.

[0046] The structure is simple, easy to assemble and produce, and improves manufacturing efficiency. The aluminum plate body and ceramic layer of the top layer of the integrated structure conduct heat evenly, ensuring temperature uniformity. The flexible layout of the copper heating circuit further improves the upper limit of the uniform temperature of the entire heating plate.

[0047] The processing method disclosed in this embodiment includes combining the top layer and the middle layer of the ceramic disk by sintering or welding. This step ensures the close combination of the layers of the disk body and improves the stability and mechanical strength of the overall structure. Next, the circuit system is sintered on the other side of the ceramic disk. This step is the key to achieving uniform heating of the hot disk, because the layout and performance of the circuit system directly affect the heating effect of the hot disk. Laser drilling is used to open screw holes on the ceramic disk. The application of this technology improves the processing accuracy and ensures the accuracy of the position and size of the screw holes, thereby ensuring the reliability of the fastening assembly. Finally, the layers of the disk body are fastened and assembled into an integrated structure by screws. This step completes the final assembly of the hot disk and ensures the stability and durability of the overall structure.

[0048] In addition, this embodiment further refines the bonding process between the top plate body and the heating plate body, and provides a variety of bonding methods to adapt to different application requirements and manufacturing conditions.

[0049] The DBC (Direct Bond Copper) eutectic sintering process is a mature technology that forms a eutectic layer between the copper foil and the ceramic substrate to achieve a close bond between the two, with high thermal conductivity and good thermal cycle performance. Under high temperature and a certain pressure, a metallurgical reaction occurs at the contact surface of the copper foil and the ceramic substrate to form a eutectic bond. In this process, the atoms of copper and ceramic diffuse with each other at the interface to form a stable eutectic structure.

[0050] The DPC (Direct Patterning Copper) direct copper plating process is a more flexible manufacturing method. It uses electrochemical methods to reduce copper ions to copper metal and deposit it on the ceramic substrate to form the required circuit pattern. The required circuit pattern can be directly formed on the ceramic substrate, reducing the complexity and cost of the manufacturing process.

[0051] The AMB (Active Metal Brazing) active metal welding process uses active metal solder to react with ceramics and copper foil at high temperatures to form high-strength welding joints, which are suitable for application scenarios requiring extremely high reliability.

[0052] The LAM (Low-Temperature Active Metal) active metal welding process is a low-temperature welding technology that uses active metal solder with a low melting point to react with the ceramic surface at a relatively low temperature to form a bond. It can achieve the bonding of metal and ceramic at a lower temperature and is suitable for the processing of heat-sensitive materials.

[0053] These processes have their own characteristics, but their common goal is to achieve a combination of high strength, high thermal conductivity and high reliability between the top plate and the heat plate. By selecting the appropriate process, the performance and cost-effectiveness of the heat plate can be optimized according to specific application requirements and manufacturing conditions.

[0054] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. A hot plate structure, characterized in that: It comprises a sandwich hot plate, wherein the top layer of the sandwich hot plate is provided with a plurality of temperature sensors, the middle layer comprises a heating plate body, and the bottom layer is a base; Wherein, a circuit system is arranged on the heating plate, and the middle layer and the top layer are connected in one piece.

2. A hot plate structure according to claim 1, characterized in that: The middle layer portion includes a ceramic disk and an insulating disk, the circuit system is arranged between the ceramic disk and the insulating disk, and the ceramic disk is fixedly connected to the top layer portion.

3. A hot plate structure according to claim 2, characterized in that: The ceramic disc is made of alumina ceramics or aluminum nitride ceramics and is fixedly connected to the top layer by sintering or welding.

4. A hot plate structure according to claim 2, characterized in that: The circuit system comprises a copper circuit layer, which is formed by etching or printing process, and the layout of the circuit layer is a spiral line type.

5. A hot plate structure according to claim 4, characterized in that: The spiral linear circuit layer includes several layers from the inside to the outside, the number of layers is proportional to the size of the disk, and the pitch of each layer is independent.

6. A hot plate structure according to claim 4, characterized in that: The spiral line circuit layer includes several layers with the same pitch, and the width and number of turns of the etching lines in each layer are different.

7. A hot plate structure according to any one of claims 1 to 6, characterized in that: The top layer is an aluminum plate, and a plurality of grooves are formed on the surface of the top layer.

8. A hot plate structure according to any one of claims 1 to 6, characterized in that: The base of the bottom layer is provided with wire outlet holes and screw holes.

9. A method for processing a hot plate structure as claimed in claim 1, characterized in that: The following steps are involved: S1: The ceramic discs of the top layer and the middle layer are combined by sintering or welding; S2: Sintering the circuit system on the other side of the ceramic disk; S3: Use laser drilling to open screw holes on the ceramic plate; S4: Assemble the various layers of the disk into an integrated structure by fastening with screws.

10. The method for processing a hot plate structure according to claim 9, characterized in that: The top plate body and the heating plate body are bonded together by a DBC eutectic sintering process / DPC direct copper electroplating process / AMB active metal welding process / LAM active metal welding process.

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