Ceramic plate for attaching wafer and temperature control method thereof

Abstract

This application relates to the technical field of semiconductor chemical mechanical polishing and discloses a ceramic plate for attaching wafers and a temperature control method thereof. The ceramic plate includes a ceramic substrate, an induction groove disposed within the ceramic substrate, an electromagnetic induction layer embedded within the induction groove, an insulating layer disposed on the surface of the electromagnetic induction layer, and an electromagnetic heating component disposed corresponding to the electromagnetic induction layer. The front surface of the ceramic substrate is the attachment surface, and the back surface of the ceramic substrate is provided with a heat dissipation microchannel connected to a coolant circulation component. The ceramic plate is heated by electromagnetic induction, thereby improving the efficiency of wax removal from the ceramic plate surface.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor chemical mechanical polishing, and in particular to a ceramic disk for attaching wafers and a temperature control method thereof. Background Art

[0002] CMP, or chemical mechanical polishing, is a surface planarization technology that combines chemical and mechanical action. During the CMP process, a wafer is mounted on a rotating polishing table while a polishing solution containing abrasive particles and chemicals is evenly sprayed onto the wafer surface. A polishing head with a polishing pad contacts the wafer surface and applies pressure. Under the relative rotation of the polishing table and polishing head, the abrasive particles mechanically remove material from the wafer surface, while the chemicals react with the surface material, forming an easily removable film, thereby flattening the wafer surface.

[0003] In the current semiconductor industry, ceramic discs play a key role in the CMP field, primarily used for attaching wafers to achieve wafer planarization. After the wafer planarization process is completed, wax will remain on the surface of the ceramic disc, which needs to be cleaned. During the cleaning process, a scraper is used to remove the wax. During the scraper removal process, the wax on the surface of the ceramic disc cools and solidifies, which can cause the scraping process to be disrupted, affecting the preparation process of other process flows. Summary of the Invention

[0004] In order to improve the efficiency of wax removal on the surface of a ceramic disk, the present application provides a ceramic disk for attaching wafers and a temperature control method thereof.

[0005] In a first aspect, the present application provides a ceramic plate for attaching wafers, which adopts the following technical solution:

[0006] A ceramic plate for attaching wafers, comprising a ceramic base, an induction groove provided in the ceramic base, an electromagnetic induction layer embedded in the induction groove; an insulating layer provided on the surface of the electromagnetic induction layer; and an electromagnetic heating component provided corresponding to the electromagnetic induction layer.

[0007] The front side of the ceramic substrate is an attachment surface, and the back side of the ceramic substrate is provided with a heat dissipation microchannel, and the heat dissipation microchannel is connected to a cooling liquid circulation component.

[0008] By employing the above-mentioned technical solution, the electromagnetic induction layer and electromagnetic heating assembly work together to prevent the wax on the ceramic disc from cooling and solidifying during wax removal by the scraper. This reduces the wax's hardness and viscosity, making the scraping process smoother and improving the efficiency of wax removal, while also preventing disruption to other manufacturing processes. Electromagnetic induction heating enables highly precise temperature control, allowing the ceramic disc's temperature to be quickly adjusted to meet the wax treatment requirements of different process stages, ensuring consistent and stable wax removal results. The insulating layer effectively prevents leakage of current generated by the electromagnetic induction layer, protecting the structural integrity of the ceramic disc, extending its service life, and ensuring safety during use. Microchannels on the back of the ceramic substrate connect to a coolant circulation assembly to dissipate excess heat generated by electromagnetic induction heating and other factors during operation, keeping the disc within the appropriate operating temperature range. This prevents excessive temperatures from impacting the disc's performance and wafer attachment, ensuring the stability and reliability of the entire process. The structural design of the ceramic disc enables it to meet the requirements of wafer attachment during the CMP process, and also meet the requirements of subsequent processes such as wax removal through temperature control. It has strong process adaptability and improves the versatility and practicality of the ceramic disc in the semiconductor manufacturing process.

[0009] Optionally, the electromagnetic heating assembly includes a heating controller, an alternating magnetic field generator and an infrared temperature sensor, and the heating controller is electrically connected to the alternating magnetic field generator and the infrared temperature sensor;

[0010] The heating controller obtains infrared temperature data from the infrared temperature sensor; and controls the operating power of the alternating magnetic field generator in an anti-correlation manner according to the infrared temperature data; the higher the infrared temperature data, the lower the operating power of the alternating magnetic field generator; and the higher the infrared temperature data, the higher the operating power of the alternating magnetic field generator.

[0011] Using this technical solution, an infrared temperature sensor monitors the ceramic plate's temperature in real time and transmits this data to the heating controller. Based on this precise infrared temperature data, the heating controller inversely adjusts the power of the alternating magnetic field generator. This means that when the ceramic plate's temperature approaches the preset value, the alternating magnetic field generator's power is reduced to prevent overheating. When the temperature is lower, the power is increased to ensure the plate's temperature remains precisely within the set range. This significantly improves temperature control accuracy and meets the stringent temperature requirements of wax treatment processes. This inversely proportional control mechanism effectively prevents the plate from overheating due to continuous high-power operation of the alternating magnetic field generator. Overheating can not only affect the plate's performance but also damage the attached wafers. Real-time power adjustment prevents overheating, ensures the safety of the plate and wafers, and extends the equipment's service life. Dynamically adjusting the alternating magnetic field generator's power based on the plate's actual temperature avoids unnecessary energy waste. When the temperature reaches the appropriate range, the generator's power is reduced, ensuring effective wax removal while reducing energy consumption. This aligns with energy conservation and emission reduction, contributing to lower production costs. The heating controller, alternating magnetic field generator, and infrared temperature sensor work together to form an automated temperature control system. This system automatically adjusts heating power based on the temperature of the ceramic disc, eliminating the need for frequent manual intervention. This increases the automation level of the production process, reduces operational errors, and improves production efficiency and product quality stability.

[0012] Optionally, the coolant circulation assembly includes a cooling controller, a circulation pump and a water temperature sensor, and the cooling controller is electrically connected to the circulation pump and the water temperature sensor;

[0013] The cooling controller obtains water temperature data from the water temperature sensor; controls the operating power of the circulation pump in a positive correlation according to the water temperature data; the higher the water temperature data, the higher the operating power of the circulation pump; the lower the water temperature data, the lower the operating power of the circulation pump.

[0014] By employing this technical solution, a water temperature sensor monitors the coolant temperature in real time and transmits this data to the cooling controller. Based on this precise water temperature data, the cooling controller adjusts the circulating pump's operating power accordingly. When the water temperature is high, the ceramic disk generates more heat. Increasing the circulating pump's operating power speeds up the coolant circulation, enhancing heat dissipation and promptly removing heat from the ceramic disk, ensuring the disk maintains an appropriate temperature. When the water temperature is low, the ceramic disk generates less heat. Reducing the circulating pump's operating power prevents energy waste caused by excessive coolant circulation, thus achieving precise control of the disk's heat dissipation. Stable heat dissipation control effectively prevents performance degradation or damage to the ceramic disk caused by excessive temperatures. By dynamically adjusting the circulating pump's power based on the water temperature, the ceramic disk is consistently maintained at an appropriate operating temperature, ensuring stability and reliability during wafer bonding and other related processes, extending its service life, and ultimately ensuring smooth semiconductor manufacturing. By controlling the circulating pump's operating power in a positive correlation with the water temperature data, energy waste caused by continuous high-power operation is avoided. When the water temperature is low, the circulating pump power is reduced, reducing unnecessary energy consumption. This allows the coolant circulation system to operate more energy-efficiently while meeting cooling requirements, meeting energy conservation and emission reduction requirements and helping to reduce production costs. The cooling controller, circulating pump, and water temperature sensor form an automated coolant circulation control system. This system automatically adjusts the operating state of the circulating pump according to changes in water temperature, eliminating the need for frequent manual intervention. This improves the automation and intelligence of the production process, reduces human error, and enhances production efficiency and product quality stability, making the entire semiconductor manufacturing process more efficient and reliable.

[0015] Optionally, the ceramic disc is made of aluminum nitride ceramic material by hot pressing and sintering, and the sensing groove is formed by laser micromachining;

[0016] The electromagnetic induction layer has a plurality of induction partitions, each of the induction partitions corresponds to the alternating magnetic field generator, and a heat insulation wall is provided around the periphery of each induction partition.

[0017] By adopting the above technical solution, the ceramic disc is made of aluminum nitride ceramic material through hot pressing and sintering. Aluminum nitride ceramic material has excellent properties such as high thermal conductivity, high hardness, high temperature resistance, and good chemical stability. The high thermal conductivity helps the ceramic disc better transfer heat, and when combined with the coolant circulation assembly, it can dissipate heat more efficiently and maintain a stable temperature. The high hardness and high temperature resistance enable the ceramic disc to withstand large pressures and temperature fluctuations during the CMP process and wax removal, making it less susceptible to damage and extending the service life of the ceramic disc. The good chemical stability reduces the possibility of chemical reactions with polishing fluids and chemical reagents, ensuring the reliability of the ceramic disc in complex process environments and improving the stability of the entire semiconductor manufacturing process. The sensing groove is formed by laser micromachining, a technology with the advantages of high precision, high processing quality, and non-contact processing. The high-precision machining ensures the accurate size, shape, and position of the sensing groove, allowing the electromagnetic induction layer to be better embedded within it, ensuring the stability and consistency of the electromagnetic induction effect. Non-contact processing avoids mechanical damage to the surface of the ceramic disc, maintains the integrity and surface quality of the ceramic disc, and is conducive to improving the performance of the ceramic disc during wafer attachment and subsequent processes. The electromagnetic induction layer has multiple induction zones, and each induction zone corresponds to an alternating magnetic field generator. This design allows independent temperature control of different areas of the ceramic disc. In actual semiconductor manufacturing processes, since the process requirements of different parts of the wafer may be different, or during the wax removal process, there may be differences in the wax residue in different areas of the ceramic disc surface. By controlling the power of the alternating magnetic field generator for each induction zone separately, the temperature of different areas of the ceramic disc can be accurately adjusted to meet the process requirements of different areas, improve the flexibility and accuracy of the ceramic disc temperature control, and thus improve the process adaptability and product quality.

[0018] Optionally, the electromagnetic induction layer is a copper wire or a copper tube; when the electromagnetic induction layer is a copper tube, the copper tube is connected to the heat dissipation microchannel.

[0019] By adopting the above technical solution, the copper wire has excellent electrical conductivity and electromagnetic induction properties. According to the principle of electromagnetic induction, when an alternating magnetic field acts on the copper wire, an induced electromotive force and induced current are generated within the wire, which in turn generates Joule heat, achieving the heating function of the ceramic disc to meet the temperature requirements of the ceramic disc during processes such as wax removal. When the electromagnetic induction layer is a copper tube and is connected to the heat dissipation microchannel, the copper tube has excellent thermal conductivity and can quickly transfer the heat generated within the ceramic disc to the heat dissipation microchannel. The coolant circulates in the heat dissipation microchannel, promptly removes this heat, achieving efficient heat dissipation, helping to maintain the temperature of the ceramic disc stable and preventing overheating that affects its performance and lifespan. Combining electromagnetic induction with heat dissipation makes the ceramic disc structure more compact. Eliminating additional heat dissipation components and complex connection structures helps improve the integration of the device, save space, and reduce system complexity and cost. Through the connection between the copper tube and the heat dissipation microchannel, the coolant can be more evenly distributed inside the ceramic disk, thereby making the heat dissipation of each part of the ceramic disk more uniform, avoiding local overheating or overcooling, and improving the temperature uniformity of the ceramic disk, which is conducive to ensuring the consistency and stability of wafer attachment and subsequent processes.

[0020] In a second aspect, the present application provides a temperature control method for a ceramic plate for attaching wafers, which adopts the following technical solution:

[0021] A temperature control method for a ceramic plate for attaching wafers is provided. The method comprises a ceramic substrate, an induction groove provided within the ceramic substrate, an electromagnetic induction layer embedded within the induction groove, an insulating layer provided on the surface of the electromagnetic induction layer, and an electromagnetic heating component provided corresponding to the electromagnetic induction layer. The electromagnetic heating component comprises a heating controller, an alternating magnetic field generator, and an infrared temperature sensor, wherein the heating controller is electrically connected to the alternating magnetic field generator and the infrared temperature sensor.

[0022] The front side of the ceramic substrate is an attachment surface, and a heat dissipation microchannel is provided on the back side of the ceramic substrate. The heat dissipation microchannel is connected to a coolant circulation component, and the coolant circulation component includes a cooling controller, a circulation pump and a water temperature sensor. The cooling controller is electrically connected to the circulation pump and the water temperature sensor.

[0023] The method comprises the following steps:

[0024] The heating controller obtains infrared temperature data from the infrared temperature sensor;

[0025] Calculating a first temperature difference between the infrared temperature data and preset heating reference temperature data;

[0026] adjusting the operating power of the alternating magnetic field generator in a positive correlation with the first temperature difference; the greater the first temperature difference, the greater the operating power of the alternating magnetic field generator; and the smaller the first temperature difference, the smaller the operating power of the alternating magnetic field generator;

[0027] The cooling controller obtains water temperature data from the water temperature sensor;

[0028] Calculating a second temperature difference between the water temperature data and a preset cooling reference temperature data;

[0029] The operating power of the circulation pump is adjusted in a positive correlation according to the second temperature difference; the larger the second temperature difference is, the greater the operating power of the circulation pump is; the smaller the second temperature difference is, the smaller the operating power of the circulation pump is.

[0030] By employing the above technical solution, the system, using infrared temperature sensors and water temperature sensors, can accurately and in real time measure the surface temperature of the ceramic disk and the coolant temperature. By calculating the difference between the actual temperature and a preset reference temperature and adjusting the power of the alternating magnetic field generator and the circulating pump accordingly, precise control of the ceramic disk temperature is achieved. During the dewaxing phase, the ceramic disk temperature is stably maintained within the optimal range for wax scraping, preventing poor dewaxing results due to excessively high or low temperatures, thereby ensuring process stability and reliability. Dynamic adjustment of the heating and cooling device power based on the deviation between the actual temperature and the preset value prevents continuous full-load operation. When the ceramic disk temperature approaches the heating reference temperature, the power of the alternating magnetic field generator is reduced to minimize unnecessary energy consumption. When the coolant temperature is low, the power of the circulating pump is reduced to conserve energy. This intelligent energy management strategy effectively reduces production costs while meeting process requirements. This method automatically adjusts the heating and cooling intensity based on the thermal fluctuations of the ceramic disk during different operating phases. Whether during wafer attachment or subsequent processes like wax removal, the system can quickly adapt to varying temperature requirements without manual intervention. For example, during wax removal, the presence of wax on the ceramic disc surface creates specific temperature requirements, and the system automatically adjusts to the appropriate temperature. Furthermore, during other process stages, the system can adapt to new requirements. Stable temperature control reduces thermal and mechanical stresses caused by temperature fluctuations on components such as the ceramic disc, electromagnetic induction layer, and cooling system. This prevents fatigue damage to components caused by frequent thermal expansion and contraction, thereby extending the overall lifespan of the equipment and reducing maintenance and replacement costs. Precise temperature control ensures the ceramic disc is always in optimal working condition, reducing process interruptions and product defects caused by temperature issues.

[0031] Optionally, the electromagnetic induction layer has a plurality of induction partitions, each of the induction partitions corresponds to the alternating magnetic field generator, and each of the induction partitions corresponds to the infrared temperature sensor;

[0032] The method further comprises the steps of:

[0033] The heating controller controls and connects a plurality of the alternating magnetic field generators and a plurality of the infrared temperature sensors;

[0034] The heating controller controls all the alternating magnetic field generators to heat the induction partitions at a set test power for a preset test duration, and obtains the partition temperature data of each of the induction partitions through the corresponding infrared temperature sensor;

[0035] According to the difference between the partition temperature data and the corresponding preset test temperature data, the adjustment gain value of the working power of the alternating magnetic field generator corresponding to the partition temperature data is anti-correlatedly adjusted; the larger the difference, the smaller the corresponding adjustment gain value of the working power of the alternating magnetic field generator; the smaller the difference, the larger the corresponding adjustment gain value of the working power of the alternating magnetic field generator.

[0036] By implementing this technical solution, multiple sensing zones, alternating magnetic field generators, and infrared temperature sensors are mapped one-to-one, enabling the heating controller to independently monitor and control each zone of the ceramic plate. Compared to overall temperature control, this avoids process deviations caused by localized temperature variations on the ceramic plate, ensuring consistent performance across different zones during processes such as wafer attachment and wax removal. For example, during wax removal, wax residue may differ between the edge and center of the ceramic plate. Zoned temperature control allows for targeted heating of these zones, enhancing wax removal effectiveness. After setting the test power and duration, the heating controller dynamically adjusts the alternating magnetic field generator gain based on the temperature changes in each sensing zone. When the difference between the zone temperature data and the preset test temperature data is small, the gain is increased, enabling the alternating magnetic field generator to respond more quickly to temperature changes and accelerating the heating process. When the difference is large, the gain is reduced to prevent temperature overshoot. This achieves dynamic optimization of the heating process, effectively improving heating efficiency and reducing overall process time.

[0037] Optionally, the method further comprises the following steps:

[0038] The heating controller controls and connects a plurality of the alternating magnetic field generators and a plurality of the infrared temperature sensors;

[0039] The heating controller controls all the alternating magnetic field generators to heat the induction partitions at a set test power for a preset test duration, and obtains the partition temperature data of each of the induction partitions through the corresponding infrared temperature sensor;

[0040] According to the difference between the partition temperature data and the corresponding preset test temperature data, the opening phase angle of the alternating magnetic field generator corresponding to the partition temperature data is positively correlated and adjusted; the larger the difference, the larger the corresponding opening phase angle of the alternating magnetic field generator; the smaller the difference, the smaller the corresponding opening phase angle of the alternating magnetic field generator.

[0041] By employing this technical solution, the AC magnetic field generator's activation phase angle is adjusted in a positive correlation based on the difference between the temperature data of each sensing zone and the preset test temperature data. When the zone temperature deviates significantly from the preset value, the activation phase angle is increased, enabling the AC magnetic field generator to operate more quickly and rapidly raising the temperature of the sensing zone. This immediate response mechanism significantly shortens the time it takes for the ceramic plate to reach the target temperature, meeting the semiconductor manufacturing process's requirement for rapid temperature adjustment, reducing waiting time, and improving overall production efficiency. In actual operation, different sensing zones may experience uneven temperature distribution due to factors such as location and heat dissipation conditions. By independently adjusting the activation phase angle of the AC magnetic field generator for each zone, temperature differences can be specifically compensated. For example, increasing the activation phase angle of the AC magnetic field generator in a zone with a lower temperature allows for faster temperature rise, effectively narrowing the temperature gap between zones and ensuring a uniform surface temperature on the ceramic plate. This provides a stable and consistent temperature environment for wafer attachment and subsequent processing, improving product quality consistency. Compared to continuous heating at a fixed power, dynamically adjusting the activation phase angle based on temperature differences avoids energy waste caused by excessive heating. When the zone temperature approaches the preset value, the activation phase angle of the alternating magnetic field generator is reduced, reducing its operating intensity. This significantly reduces energy consumption while maintaining effective temperature control, aligning with the concept of green production and helping companies lower production costs. Stable and precise temperature control alleviates the stress on equipment caused by frequent temperature fluctuations and overloads. By properly adjusting the activation phase angle of the alternating magnetic field generator, the equipment is protected from prolonged high loads, reducing wear and aging of components, extending its overall service life, and reducing maintenance and replacement costs, ensuring long-term, stable production for the company.

[0042] Optionally, the method further comprises the following steps:

[0043] Calculate the discrete values ​​of the plurality of partition temperature data as partition discrete values;

[0044] If the partition discrete value is greater than a preset reference discrete value, the coolant circulation component is started and continues to run for a preset working time, and the difference between the partition discrete value and the reference discrete value is calculated as a discrete difference;

[0045] The value of the working time is adjusted according to the positive correlation of the discrete difference; the larger the discrete difference, the longer the value of the working time; the smaller the discrete difference, the larger the value of the working time.

[0046] By implementing this technical solution, during the dewaxing process on a ceramic plate, temperature variations vary across zones due to the uneven amount and distribution of residual wax. By calculating the discrete values ​​of the zone temperature data and comparing them with a reference discrete value, the degree of temperature uniformity can be assessed. When the zone discrete value exceeds the reference discrete value, the coolant circulation component is activated and its operating time is adjusted based on the discrete difference to remove excess heat, balance the temperatures across zones, and avoid local overheating or overcooling, thereby improving dewaxing effectiveness and maintaining a stable temperature environment for the wafers. Independent zone temperature control combined with coolant circulation control based on temperature discrete values ​​allows precise regulation of heating and heat dissipation based on the residual wax content in each zone, preventing incomplete dewaxing and carbonization of the wax layer and improving product yield. Furthermore, monitoring the zone discrete values ​​allows for optimal control of the coolant circulation component's operating time, extending the operating time to ensure temperature uniformity when temperature differences are large and shortening the operating time when temperatures are relatively uniform. This avoids energy waste, achieves efficient energy utilization, and reduces production costs. Furthermore, this method allows for timely temperature adjustments across zones, preventing damage to the ceramic plate and wafers from locally high temperatures, reducing thermal stress on the equipment, extending its lifespan, and ensuring wafer quality and performance.

[0047] Optionally, the method further comprises the following steps:

[0048] Calculating the difference between the temperature data of a plurality of adjacent partitions to obtain a plurality of temperature difference values;

[0049] Calculate the discrete values ​​of the plurality of temperature differences as difference discrete values;

[0050] The operating speed of the circulation pump is adjusted according to the positive correlation of the difference discrete value; the larger the difference discrete value, the greater the operating speed of the circulation pump; the smaller the difference discrete value, the smaller the operating speed of the circulation pump.

[0051] By implementing this technical solution, during the wax removal process, uneven wax residue distribution can cause temperature fluctuations in different zones of the ceramic disc to be out of sync. By calculating the temperature difference between adjacent zones and the discrete value of the differential, areas of temperature anomalies can be precisely located. When the discrete value of the differential is large, indicating unstable temperature distribution, increasing the circulation pump speed can enhance heat dissipation and promote heat transfer, preventing abnormal wax melting and wafer damage, ensuring smooth process execution and reducing defective product rates. This solution also flexibly adapts to the temperature uniformity requirements of different semiconductor manufacturing processes for the ceramic disc. When the discrete value of the differential is small, indicating relatively uniform temperature distribution, reducing the circulation pump speed can avoid energy waste and lower production costs. Compared to traditional fixed speed control, dynamically adjusting the circulation pump speed based on the discrete value of the differential effectively allocates heat dissipation resources and reduces energy consumption. Furthermore, precisely controlling the circulation pump speed balances the temperature across the ceramic disc, reducing thermal stress on the equipment, extending the service life of key components such as the ceramic disc and the electromagnetic induction layer, reducing equipment maintenance costs, stabilizing equipment operation, and ensuring the continuity and reliability of the production process.

[0052] In summary, this application includes at least one of the following beneficial technical effects:

[0053] The electromagnetic induction layer works together with the electromagnetic heating component to heat the ceramic disc when the scraper is removing wax, reducing the hardness and viscosity of the wax, improving the removal efficiency, and avoiding affecting the subsequent process flow.

[0054] The temperature is monitored in real time by infrared temperature sensors and water temperature sensors. The power of the alternating magnetic field generator and the circulation pump are adjusted respectively in combination with the heating controller and the cooling controller to achieve precise control of the temperature of the ceramic disk and ensure process stability and reliability.

[0055] Dynamically adjust the power of heating and cooling equipment based on the deviation between the actual temperature and the preset value to avoid continuous full-load operation of the equipment, reduce energy consumption and lower production costs.

[0056] The heating controller, alternating magnetic field generator, infrared temperature sensor, cooling controller, circulation pump, and water temperature sensor work together to form an automated temperature control and coolant circulation control system, reducing human operating errors and improving production efficiency and product quality stability.

[0057] The ceramic disk is made of aluminum nitride ceramic material, which has the characteristics of high thermal conductivity, high hardness, high temperature resistance and good chemical stability, extending the service life of the ceramic disk and improving the stability of the semiconductor manufacturing process.

[0058] The sensing groove is formed by laser micromachining to ensure the accuracy and stability of the embedding of the electromagnetic induction layer, avoid mechanical damage to the surface of the ceramic disk, and improve the performance of the ceramic disk.

[0059] The multiple induction zones of the electromagnetic induction layer correspond to the alternating magnetic field generators and infrared temperature sensors respectively, which can independently control the temperature of different areas of the ceramic disk to meet the process requirements of different areas, improve the flexibility and accuracy of temperature control, and enhance process adaptability and product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 A side view of the ceramic plate used to attach wafers.

[0061] Figure 2 yes Figure 1 Cross-sectional view of AA in the figure.

[0062] Figure 3 This is a bottom view of the ceramic plate used to attach wafers. Figure 1 Middle B direction view.

[0063] Figure 4 yes Figure 3 Enlarged view of part C in the middle.

[0064] Figure numerals: 1. Ceramic substrate; 2. Electromagnetic induction layer; 3. Insulation layer; 4. Heat dissipation microchannel; 5. Induction partition; 6. Thermal insulation wall. DETAILED DESCRIPTION

[0065] Embodiments of the present application are described in detail below, examples of which are illustrated in the accompanying drawings.

[0066] Throughout this specification, reference to the terms "certain embodiments," "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0067] The present application discloses a ceramic plate for attaching a wafer, referring to Figure 1 and Figure 2, including a disc-shaped ceramic substrate 1. Induction grooves are formed inside the ceramic substrate 1 by laser micromachining. This machining method has high precision and can ensure the accuracy of the size, shape and position of the induction grooves, avoiding mechanical damage to the surface of the ceramic disk. An electromagnetic induction layer 2 is embedded in the induction groove, and an alternating magnetic field is generated by the coil of the external electromagnetic induction layer 2, so that the electromagnetic induction layer 2 inside the ceramic disk generates eddy currents, thereby achieving rapid heating in specific areas. The surface of the electromagnetic induction layer 2 is covered with an aluminum nitride insulating coating through plasma spraying technology to form an insulating layer 3, which prevents current leakage, protects the structural integrity of the ceramic disk, and improves safety in use.

[0068] The ceramic disc is made of aluminum nitride ceramic material through hot pressing and sintering, ensuring a low thermal expansion coefficient and high thermal conductivity. Aluminum nitride ceramic material has excellent properties such as high thermal conductivity, high hardness, high temperature resistance, and good chemical stability. High thermal conductivity helps the ceramic disc better transfer heat. In combination with the coolant circulation component, it can dissipate heat more efficiently and maintain the temperature of the ceramic disc. The high hardness and high temperature resistance enable the ceramic disc to withstand large pressures and temperature fluctuations during the CMP process and wax removal process, making it less susceptible to damage and extending the service life of the ceramic disc. The good chemical stability reduces the possibility of chemical reactions with polishing fluids and chemical reagents, ensuring the reliability of the ceramic disc in complex process environments and improving the stability of the entire semiconductor manufacturing process.

[0069] The electromagnetic induction layer 2 is equipped with an electromagnetic heating assembly. This assembly includes a heating controller, an alternating magnetic field generator, and an infrared temperature sensor, all electrically connected to each other. The infrared temperature sensor monitors the temperature of the ceramic disc in real time and transmits data to the heating controller. The heating controller then inversely controls the operating power of the alternating magnetic field generator based on the infrared temperature data. For example, during the dewaxing process on a scraper, when the ceramic disc temperature approaches the preset dewaxing temperature, the alternating magnetic field generator power is reduced to prevent the temperature from overheating. When the temperature is lower, the power is increased to ensure that the ceramic disc temperature remains precisely within the set range, thus improving the stability of the dewaxing effect. The infrared temperature sensor monitors the ceramic disc temperature in real time and transmits data to the heating controller. Based on this precise infrared temperature data, the heating controller inversely adjusts the operating power of the alternating magnetic field generator. This means that when the ceramic disc temperature approaches the preset value, the alternating magnetic field generator power is reduced to prevent the temperature from overheating; when the temperature is lower, the power is increased to ensure that the ceramic disc temperature remains precisely within the set range. This significantly improves the accuracy of temperature control and meets the stringent temperature requirements of wax treatment processes on ceramic disc surfaces. An anti-correlation control mechanism effectively prevents the ceramic plate from overheating due to continuous high-power operation of the alternating magnetic field generator. Overheating can not only affect the performance of the ceramic plate itself but also damage the attached wafers. Real-time power adjustment prevents overheating, ensures the safety of the ceramic plate and wafers, and extends the life of the equipment. Dynamic adjustment of the alternating magnetic field generator power based on the actual temperature of the ceramic plate avoids unnecessary energy waste. When the temperature reaches the appropriate range, the generator power is reduced. This ensures effective wax removal while reducing energy consumption, aligning with energy conservation and emission reduction, and helping to lower production costs. The heating controller, alternating magnetic field generator, and infrared temperature sensor work together to form an automated temperature control system. Heating power is automatically adjusted according to changes in the ceramic plate temperature, eliminating the need for frequent manual intervention. This increases the automation level of the production process, reduces human error, and improves production efficiency and product quality consistency.

[0070] Reference Figure 3 and Figure 4 The front surface of the ceramic substrate 1 serves as the attachment surface, while the back surface of the ceramic substrate 1 defines a heat dissipation microchannel 4, which is connected to a coolant circulation assembly. In this embodiment, the heat dissipation microchannel 4 comprises a plurality of hexagonal countersunk holes arranged in an array, increasing the heat dissipation area and allowing heat to be removed by the liquid flowing through the coolant circulation assembly. The coolant circulation assembly includes a cooling controller, a circulation pump, and a water temperature sensor, all of which are electrically connected to the cooling controller, the circulation pump, and the water temperature sensor.

[0071] The cooling controller obtains water temperature data from the water temperature sensor; and controls the working power of the circulation pump according to the positive correlation of the water temperature data; the higher the water temperature data, the higher the working power of the circulation pump; and the lower the water temperature data, the lower the working power of the circulation pump.

[0072] For example, during the initial dewaxing process, the ceramic disc is cold, and the water temperature sensor detects a coolant temperature of 28°C. The cooling controller then reduces the circulating pump's power, allowing it to operate at a relatively low power level, for example, 30% of its rated power. When electromagnetic induction heating of the ceramic disc begins to dewax, its temperature rapidly rises, and the coolant reaches 38°C. Based on this rising water temperature, the cooling controller increases the circulating pump's power to 60% of its rated power, accelerating coolant circulation and preventing overheating of the ceramic disc, which could affect dewaxing and its performance.

[0073] The water temperature sensor monitors the coolant temperature in real time and transmits this data to the cooling controller. Based on this precise water temperature data, the cooling controller adjusts the circulating pump's operating power in direct correlation. When the water temperature is high, the ceramic disk generates more heat. Increasing the circulating pump's operating power speeds up the coolant circulation, enhancing heat dissipation and promptly removing heat from the ceramic disk, ensuring the disk's temperature remains within the appropriate range. When the water temperature is low, the ceramic disk generates less heat. Reducing the circulating pump's operating power prevents energy waste from excessive coolant circulation, thus achieving precise control of the disk's heat dissipation. Stable heat dissipation control effectively prevents performance degradation or damage to the ceramic disk caused by excessive temperatures. By dynamically adjusting the circulating pump's power based on the water temperature, the ceramic disk is consistently maintained at an appropriate operating temperature, ensuring stability and reliability during wafer bonding and other related processes, extending its service life, and ultimately ensuring smooth semiconductor manufacturing. By controlling the circulating pump's operating power in direct correlation with the water temperature data, energy waste caused by continuous high-power operation is avoided. When the water temperature is low, the circulating pump power is reduced, reducing unnecessary energy consumption. This allows the coolant circulation system to operate more energy-efficiently while meeting cooling requirements, meeting energy conservation and emission reduction requirements and helping to reduce production costs. The cooling controller, circulating pump, and water temperature sensor form an automated coolant circulation control system. This system automatically adjusts the operating state of the circulating pump according to changes in water temperature, eliminating the need for frequent manual intervention. This improves the automation and intelligence of the production process, reduces human error, and enhances production efficiency and product quality stability, making the entire semiconductor manufacturing process more efficient and reliable.

[0074] There are two implementations of the electromagnetic induction layer 2:

[0075] The first method uses copper wire as the electromagnetic induction layer 2, in the form of a spiral coil. Copper wire has excellent electrical conductivity and electromagnetic induction properties. According to the principle of electromagnetic induction, when an alternating magnetic field acts on the copper wire, an induced electromotive force and an induced current are generated within the wire, generating Joule heating. During the wax removal process, this method can meet the temperature requirements of the ceramic disc, reduce the hardness and viscosity of the wax, and make the wax removal process smoother.

[0076] The second type is a copper tube as the electromagnetic induction layer 2. A copper tube is used as the electromagnetic induction layer 2. The copper tube is also in the shape of a spiral coil and is connected to the heat dissipation microchannel 4. The copper tube has good thermal conductivity and can quickly transfer the heat generated inside the ceramic disk to the heat dissipation microchannel 4. The coolant circulates in the heat dissipation microchannel 4, taking away the heat in time to achieve efficient heat dissipation. Combining electromagnetic induction with heat dissipation function makes the structure of the ceramic disk more compact. It reduces additional heat dissipation components and complex connection structures, which is conducive to improving the integration of the equipment, saving space, and also reducing the complexity and cost of the system. Through the connection between the copper tube and the heat dissipation microchannel 4, the coolant can be more evenly distributed inside the ceramic disk, so that the heat dissipation of each part of the ceramic disk is more uniform, avoiding local overheating or overcooling, and improving the uniformity of the temperature of the ceramic disk, which is conducive to ensuring the consistency and stability of wafer attachment and subsequent processes.

[0077] In actual semiconductor manufacturing processes, because the process requirements for different parts of the wafer may vary, or during the wax removal process, the wax residue in different areas of the ceramic disk surface may vary, the electromagnetic induction layer 2 has multiple induction zones 5. In this embodiment, the induction zones 5 are shaped like equally divided sectors. Each induction zone 5 corresponds to an alternating magnetic field generator, and each independent area can be independently controlled to generate heat. This allows for precise temperature adjustment of different areas of the ceramic disk to meet the process requirements of different areas, improves the flexibility and accuracy of the ceramic disk temperature control, and thereby enhances the process adaptability and product quality.

[0078] In order to better achieve individual control of heating, a heat insulation wall 6 is provided around the periphery of each sensing zone 5 . The heat insulation wall 6 is made of a heat insulation material to form a shielding outer wall to reduce temperature interference between adjacent sensing zones 5 .

[0079] In semiconductor manufacturing, the electromagnetic induction layer 2 works in conjunction with the electromagnetic heating component, playing a key role in the wax removal process performed by the scraper. Electromagnetic induction heating allows the wax on the ceramic disc surface to break free from its cooled and solidified state, effectively reducing its hardness and viscosity. This change allows for smoother wax removal during the scraper process, significantly improving the efficiency of wax removal from the ceramic disc surface and preventing untimely or incomplete wax removal from impacting other manufacturing processes. Electromagnetic induction heating offers precise temperature control, enabling rapid adjustment of the ceramic disc temperature based on actual needs. This ensures consistent and stable wax removal results at every stage of the process, while meeting wax treatment requirements. The proper placement of the insulating layer 3 is crucial, effectively preventing leakage of the current generated by the electromagnetic induction layer 2. This not only protects the structural integrity of the ceramic disc and extends its service life, but also ensures operator and equipment safety during operation. The heat dissipation microchannels 4 on the back of the ceramic substrate 1 are interconnected with the coolant circulation component, effectively dissipating excess heat generated by electromagnetic induction heating and other factors during the operation of the ceramic disc. This ensures the ceramic plate remains within the appropriate operating temperature range, preventing adverse effects on the plate's performance and wafer attachment due to excessive temperatures, thereby ensuring the stability and reliability of the entire process. The unique structural design of this ceramic plate not only meets the requirements of wafer attachment during the chemical mechanical polishing (CMP) process, but also meets the requirements of subsequent processes such as wax removal through precise temperature control. This design gives the ceramic plate strong process adaptability, greatly improving its versatility and practicality in semiconductor manufacturing.

[0080] The present application also discloses a temperature control method for a ceramic disk for attaching wafers. The method is based on a ceramic substrate 1, which serves as a core component. High-precision laser micromachining technology forms an induction groove within the ceramic substrate 1. An electromagnetic induction layer 2 is precisely embedded within the induction groove. To prevent leakage of current generated by the electromagnetic induction layer 2, a layer of aluminum nitride insulating coating is applied to its surface using plasma spraying technology, forming an insulating layer 3. An electromagnetic heating assembly is configured corresponding to the electromagnetic induction layer 2. The electromagnetic heating assembly consists of a heating controller, an alternating magnetic field generator, and an infrared temperature sensor. These three components are electrically connected via a stable circuit, establishing a precise temperature sensing and heating control system. Furthermore, the front surface of the ceramic substrate 1 serves as the attachment surface specifically for attaching wafers. The back surface of the ceramic substrate 1 is provided with a heat dissipation microchannel 4, which is connected to a coolant circulation assembly. The coolant circulation assembly includes a cooling controller, a circulation pump, and a water temperature sensor. These three components are also electrically connected to collaboratively control the heat dissipation of the ceramic disk.

[0081] The method comprises the following steps:

[0082] The heating controller first acquires infrared temperature data from the ceramic disk's surface, as monitored in real time by an infrared temperature sensor. It then compares this infrared temperature data with a pre-set heating reference temperature based on process requirements, calculating a first temperature difference between the two. Based on this difference, the heating controller positively correlates the power of the alternating magnetic field generator. A larger first temperature difference indicates a greater distance between the ceramic disk's current temperature and the preset heating reference temperature, and the alternating magnetic field generator's power level increases accordingly. Conversely, a smaller first temperature difference results in a lower power level.

[0083] For example, in the dewaxing process of a scraper in the semiconductor manufacturing process, the preset heating reference temperature is 80°C. During the initial dewaxing phase, the infrared temperature sensor detects a surface temperature of 30°C on the ceramic disc. This first temperature difference is as high as 50°C. The heating controller responds by significantly increasing the power of the alternating magnetic field generator, rapidly heating the disc. As the disc's temperature gradually rises, once the detected temperature reaches 75°C, the first temperature difference decreases to 5°C. The heating controller then reduces the power of the alternating magnetic field generator, slowing the heating process and preventing overheating.

[0084] The cooling controller obtains real-time coolant temperature data collected by the water temperature sensor and compares it with the preset cooling reference temperature to calculate a second temperature difference. The circulating pump's operating power is then adjusted in a positive correlation with the second temperature difference. Specifically, the greater the second temperature difference, the greater the circulating pump's operating power; the smaller the second temperature difference, the lower the circulating pump's operating power.

[0085] Assume the preset cooling reference temperature is 25°C. At the beginning of dewaxing, the ceramic disc generates little heat. The water temperature sensor detects a coolant temperature of 22°C, with a second temperature difference of 3°C. The cooling controller reduces the operating power of the circulation pump, reducing the coolant circulation flow rate to avoid energy waste caused by excessive cooling. As dewaxing continues, the ceramic disc generates significant heat due to factors such as electromagnetic induction heating. The coolant temperature rises to 30°C, and the second temperature difference widens to 5°C. The cooling controller then increases the operating power of the circulation pump, accelerating the coolant circulation, enhancing heat dissipation, and ensuring a stable temperature for the ceramic disc.

[0086] This temperature control method has significant advantages. With the help of infrared temperature sensors and water temperature sensors, the system can obtain the surface temperature of the ceramic disc and the coolant temperature in real time and accurately. By calculating the difference between the actual temperature and the preset reference temperature, and adjusting the power of the alternating magnetic field generator in an anti-correlated manner and the power of the circulating pump in a positive correlation accordingly, the temperature of the ceramic disc can be precisely controlled. During the dewaxing stage, the temperature of the ceramic disc can be stably maintained within the most suitable range for scraping wax, avoiding carbonization of the wax layer due to excessively high temperature, which affects the quality of dewaxing, or the inability to effectively reduce the hardness and viscosity of the wax due to excessively low temperature, which makes scraping wax difficult, thereby ensuring the stability and reliability of the process.

[0087] Dynamically adjusting the power of the heating and cooling equipment based on the deviation between the actual temperature and the preset value prevents continuous full-load operation. When the ceramic disc temperature approaches the heating reference temperature, the alternating magnetic field generator's operating power is reduced, reducing unnecessary energy consumption. When the coolant temperature is low, the circulating pump's operating power is reduced, saving energy. This intelligent energy management strategy effectively reduces production costs while meeting process requirements.

[0088] This method automatically adjusts heating and cooling intensity based on the thermal fluctuations of the ceramic platen during different operating stages. Whether during wafer attachment or subsequent processes like wax removal, it can quickly adapt to varying temperature requirements without manual intervention. For example, during CMP, the temperature requirements for the ceramic platen differ significantly from those during wax removal. The system automatically identifies these differences and quickly adjusts to the appropriate temperature.

[0089] Stable temperature control reduces thermal and mechanical stresses caused by temperature fluctuations on components such as the ceramic disk, electromagnetic induction layer 2, and cooling system. This prevents fatigue damage to components caused by frequent thermal expansion and contraction, thereby extending the overall service life of the equipment and reducing maintenance and replacement costs. Precise temperature control ensures the ceramic disk is always in optimal working condition, reducing process interruptions and product defects caused by temperature issues, thereby improving semiconductor manufacturing efficiency and product quality.

[0090] During the wax removal process, different areas of the ceramic disc surface may have varying levels of wax residue and thickness, requiring different temperatures. Therefore, the electromagnetic induction layer 2 is divided into multiple induction zones 5. Each induction zone 5 is equipped with a dedicated alternating magnetic field generator and infrared temperature sensor. Each induction zone 5 is also surrounded by a thermal insulation wall 6 made of insulating material.

[0091] Based on the above hardware structure, the temperature control method further includes the following steps:

[0092] The heating controller is connected to control a plurality of alternating magnetic field generators and a plurality of infrared temperature sensors.

[0093] Before officially entering the production process, the heating controller controls all alternating magnetic field generators to heat each induction zone 5 at a preset test power for a preset test duration. During this time, the infrared temperature sensor corresponding to each induction zone 5 monitors temperature changes in real time and obtains zone temperature data for each induction zone 5.

[0094] The heating controller compares the acquired zone temperature data with the corresponding preset test temperature data and calculates the difference between the two. Based on this difference, the control gain of the alternating magnetic field generator's operating power corresponding to the zone temperature data is inversely adjusted. Specifically, the larger the difference, the smaller the corresponding alternating magnetic field generator's operating power gain; the smaller the difference, the larger the corresponding alternating magnetic field generator's operating power gain.

[0095] For example, the ceramic disk is circular and evenly divided into six sector-shaped sensing zones 5, labeled F1, F2, F3, F4, F5, and F6. Each sector has its own dedicated alternating magnetic field generator and infrared temperature sensor, and thermal insulation walls 6 are installed around each sector to prevent heat from interfering with each other. The preset test temperature is 95°C, and the heating controller first controls all alternating magnetic field generators to heat each sector at a test power of 130W for 7 minutes.

[0096] F1 partition:

[0097] Temperature detection: After 7 minutes, the infrared temperature sensor in the F1 zone reports a temperature of 80°C, which is 15°C lower than the preset test temperature. For example, if the wax layer in this zone is thicker, the temperature will rise slowly.

[0098] Adjustment of Gain: Due to the large difference, the heating controller reduces the gain of the alternating magnetic field generator in the F1 zone from the initial 1.0 to 0.3. If the F1 zone temperature continues to rise slowly and the power needs to be increased, the power increase will be controlled within 5W each time to prevent rapid temperature rise that may affect the dewaxing effect.

[0099] F2 partition:

[0100] Temperature detection: The temperature of this zone is 85°C, which is 10°C different from the preset temperature. For example, the wax layer thickness is thinner than that of the F1 zone.

[0101] Adjusting the Gain: The heating controller adjusts the gain of the alternating magnetic field generator in zone F2 to 0.6. When heating up, increase the power by approximately 7W each time to allow the zone to approach the preset temperature more quickly.

[0102] F3 partition:

[0103] Temperature detection: The temperature is 90°C, which is 5°C different from the preset temperature. The wax layer in this area is thinner.

[0104] Adjustment of the gain value: The gain value has been increased to 0.9. If the temperature rise trend slows down, the heating controller will increase the power by about 10W at a time to make the F3 zone reach the preset temperature as soon as possible.

[0105] F4 partition:

[0106] Temperature detection: The temperature is 92°C, which is 3°C different from the preset temperature. The wax layer in the partition is thinner and heats up faster.

[0107] Adjust the gain: The heating controller increases the gain of the F4 zone alternating magnetic field generator to 1.2. At this point, the temperature is close to the preset value and requires fine-tuning. For slight temperature fluctuations, the power adjustment is controlled at approximately 2W each time.

[0108] F5 partition:

[0109] Temperature detection: The temperature is 94°C, which is 1°C away from the preset temperature. The wax layer in this area is very thin, and the temperature is close to the preset value.

[0110] Adjust the gain value: The gain value is further increased to 1.4. When a slight temperature deviation is detected, the alternating magnetic field generator responds quickly and controls the power adjustment amplitude to about 1W each time to ensure temperature stability.

[0111] F6 partition:

[0112] Temperature detection: The temperature is 78°C, which is 17°C different from the preset temperature. The wax layer in this partition is the thickest among the six partitions.

[0113] Gain adjustment: The gain is reduced to 0.2. Subsequent power increases are slow, not exceeding 3W at a time, to avoid temperature overshoot.

[0114] The six sectors of the circular ceramic disc are independently temperature-monitored and controlled. The heating controller dynamically adjusts the gain of the alternating magnetic field generator based on the difference between the actual temperature of each sector and the preset temperature. This approach allows for targeted heating based on the wax residue in each sector, avoiding process deviations caused by localized temperature variations, improving dewaxing results, and dynamically optimizing the heating process, increasing heating efficiency and reducing overall process time, thereby ensuring the quality and consistency of the wafer dewaxing process.

[0115] By pairing multiple sensing zones, alternating magnetic field generators, and infrared temperature sensors, the heating controller can independently monitor and control each zone of the ceramic platen. Compared to overall temperature control, this avoids process deviations caused by localized temperature variations on the ceramic platen, ensuring consistent performance across different zones of the wafer dewaxing process.

[0116] Taking the wax removal process as an example, in the actual production process, there are often differences in the wax residue at the edge and center of the ceramic disk. Since the heat dissipates faster at the edge, there is relatively more wax residue, and the degree of solidification may be more serious; while the heat dissipation at the center is slower, and the wax residue is relatively less. Through zoned temperature control, when it is detected that the zoned temperature data of the edge area of ​​the ceramic disk is significantly different from the preset test temperature data, the heating controller will reduce the adjustment gain value of the alternating magnetic field generator in this area, increase the power at a lower rate, and avoid temperature overshoot that causes carbonization of the wax layer in the edge area. On the contrary, for the central area, if the difference between the zoned temperature data and the preset test temperature data is small, the heating controller will increase the adjustment gain value of the alternating magnetic field generator in this area, so that it responds to temperature changes more quickly and accelerates the heating process, thereby performing targeted heating on different areas and significantly improving the wax removal effect.

[0117] After setting the test power and duration, the heating controller can dynamically adjust the adjustment gain value of the alternating magnetic field generator according to the temperature changes of each induction zone 5. When the difference between the zone temperature data and the preset test temperature data is small, the adjustment gain value is increased so that the alternating magnetic field generator can respond to temperature changes more quickly and accelerate the heating process; when the difference is large, the adjustment gain value is reduced to prevent temperature overshoot, thereby achieving dynamic optimization of the heating process, effectively improving heating efficiency, and reducing overall process time. In the wafer attachment process, different areas have different temperature response speeds and final temperature requirements. Through this dynamically optimized heating control method, the temperature of each area can be quickly and accurately adjusted to the appropriate range, greatly improving production efficiency and ensuring product quality.

[0118] Based on the unique multi-zone design of the ceramic plate, the temperature of each sensing zone 5 is further refined and controlled. The method also includes the following steps:

[0119] The heating controller is connected to control a plurality of alternating magnetic field generators and a plurality of infrared temperature sensors.

[0120] Before officially entering production, the heating controller instructs all alternating magnetic field generators to heat each induction zone 5 at a preset test power. This heating process lasts for the preset test duration. During this time, the infrared temperature sensor corresponding to each induction zone 5 monitors temperature changes in real time and feeds the collected temperature data for each induction zone 5 back to the heating controller.

[0121] The heating controller compares the acquired zone temperature data with the corresponding preset test temperature data and calculates the difference between the two. Based on this difference, the activation phase angle of the alternating magnetic field generator corresponding to the zone temperature data is adjusted in a positive correlation. In other words, the larger the difference, the larger the activation phase angle of the alternating magnetic field generator; the smaller the difference, the smaller the activation phase angle of the alternating magnetic field generator.

[0122] In the dewaxing process of a semiconductor scraper, a circular ceramic disc is evenly divided into six sector-shaped induction zones 5 (F1, F2, F3, F4, F5, and F6). Each zone is equipped with a dedicated alternating magnetic field generator and infrared temperature sensor, surrounded by a thermal insulation wall 6. The preset test temperature is 95°C. The heating controller first controls all alternating magnetic field generators to heat each zone at a test power of 130W for 7 minutes.

[0123] Conditions of each partition and phase angle adjustment:

[0124] F1 partition:

[0125] Temperature detection and difference calculation: After 7 minutes, the infrared temperature sensor in partition F1 reported a temperature of 80°C, a 15°C difference from the preset test temperature. This partition did not reach the preset temperature.

[0126] Phase Angle Adjustment: Based on the positive correlation principle, the heating controller increases the phase angle of the alternating magnetic field generator corresponding to the F1 zone from the initial 30° to 80°. The larger phase angle enables the alternating magnetic field generator to start working more quickly, enhancing the heating effect and allowing the temperature of the F1 zone to rise more quickly, narrowing the gap with the preset temperature.

[0127] F2 partition:

[0128] Temperature detection and difference calculation: The temperature in this zone is 85°C, which is 10°C away from the preset temperature. Compared to the F1 zone, the difference is smaller.

[0129] Phase angle adjustment: The heating controller adjusts the phase angle of the alternating magnetic field generator in zone F2 to 60°. This angle is smaller than the adjustment angle for zone F1, but still allows the zone to heat up at a suitable rate, gradually approaching the preset temperature.

[0130] F3 partition:

[0131] Temperature detection and difference calculation: The temperature is 90°C, which is 5°C away from the preset temperature. This indicates that the zone is closer to the preset temperature.

[0132] Turn-on phase angle adjustment: Adjust the turn-on phase angle to 45°. A smaller turn-on phase angle reduces the operating intensity of the alternating magnetic field generator, preventing the temperature from rising too quickly and exceeding the preset value, ensuring that the temperature approaches the target steadily.

[0133] F4 partition:

[0134] Temperature detection and difference calculation: The temperature is 92°C, which is 3°C away from the preset temperature. The temperature is very close to the preset value.

[0135] Phase Angle Adjustment: The heating controller adjusts the phase angle of the alternating magnetic field generator in the F4 zone to 35°. By fine-tuning the phase angle, precise temperature control is achieved, ensuring that the temperature in this zone steadily approaches the preset temperature.

[0136] F5 partition:

[0137] Temperature detection and difference calculation: The temperature is 94°C, which is 1°C different from the preset temperature.

[0138] Phase Angle Adjustment: The phase angle is further reduced to 32°. This subtle adjustment ensures that the temperature of the zone remains stable near the preset value, avoiding temperature fluctuations.

[0139] F6 partition:

[0140] Temperature detection and difference calculation: The temperature is 78°C, which is 17°C away from the preset temperature. This is the largest difference from the preset temperature among the six zones.

[0141] Phase Angle Adjustment: The heating controller increases the phase angle of the alternating magnetic field generator in zone F6 to 90°. This maximizes the generator's efficiency and accelerates the heating of that zone to reach the preset temperature as quickly as possible.

[0142] By analyzing the difference between the temperature data of each sensing zone 5 and the preset temperature data and adjusting the activation phase angle of the alternating magnetic field generator in a positive correlation, precise heating control can be achieved based on the actual temperature conditions of each zone. This refined control method ensures that each zone heats up to the preset temperature at the most appropriate rate, avoiding localized overheating or underheating. This further improves the temperature uniformity and stability of each zone of the ceramic plate, providing a more accurate and reliable temperature environment for the wafer dewaxing process, thereby improving dewaxing results and product quality.

[0143] To ensure that the ceramic plate for attaching wafers always maintains a uniform and stable temperature environment during the semiconductor manufacturing process, the method further includes the following steps:

[0144] The heating controller continuously collects zone temperature data from the infrared temperature sensors corresponding to multiple sensing zones 5 and uses statistical methods to calculate the discrete value of this data. The result is the zone discrete value. The discrete value is a key indicator of data dispersion. In this scenario, it can intuitively reflect the degree of temperature difference between the various sensing zones 5 of the ceramic disk.

[0145] The calculated partition discrete value is compared with the preset reference discrete value. If the partition discrete value is greater than the reference discrete value, this indicates that the temperature distribution in each area of ​​the ceramic disk is severely uneven. At this time, the heating controller will immediately issue a command to start the coolant circulation component. After the coolant circulation component is started, it will continue to operate for the preset working time. During this time, the coolant circulates in the heat dissipation microchannels 4 on the back of the ceramic disk, removing excess heat generated by electromagnetic induction heating and other factors, and helping to balance the temperature between the partitions.

[0146] While the coolant circulation component is operating, the heating controller calculates the difference between the partition discrete value and the reference discrete value, known as the discrete difference. Based on this discrete difference, the coolant circulation component's operating hours are adjusted in a positive correlation. A larger discrete difference indicates greater temperature unevenness, and the system will increase the coolant circulation component's operating hours accordingly to allow for more efficient heat exchange and improve temperature distribution. A smaller discrete difference results in a shorter operating time to avoid overcooling, thereby ensuring temperature uniformity and reducing energy consumption.

[0147] Assume that the temperature difference between the partitions is large: During the dewaxing process, the temperatures of the six partitions are collected, and the temperature data obtained are 80°C, 95°C, 100°C, 85°C, 110°C, and 90°C respectively. Calculation shows that the discrete value of the partition is 13.2°C, which is greater than the reference discrete value of 12°C. The system immediately starts the coolant circulation component and calculates the discrete difference as 13.2-12=1.2°C. Since the discrete difference is positive, and according to the positive correlation regulation rule, the working time of the coolant circulation component needs to be extended. Therefore, the working time is extended from the preset 10 minutes to 13 minutes to enhance heat dissipation and balance the temperature of each partition. After 13 minutes of coolant circulation, the temperature of each partition is tested again, and it is found that the temperature distribution is more uniform, the discrete value is reduced to 10°C, the dewaxing effect is significantly improved, and the dewaxing quality problems caused by local temperatures being too high or too low are effectively avoided.

[0148] Assuming small temperature differences between zones: Temperature collection and discrete value calculation: In another dewaxing operation, the temperature data for the six zones were 92°C, 94°C, 93°C, 95°C, 92°C, and 94°C, respectively. After calculation, the zone discrete value was 1.3°C, significantly lower than the reference discrete value of 12°C. Although the zone discrete value was lower than the reference discrete value at this time, the system still activated the coolant circulation component to maintain temperature stability. The calculated discrete difference was 1.3-12=-10.7°C. According to the positive correlation regulation rule, the working time should be shortened when the discrete difference is negative, so the working time was shortened from the preset 10 minutes to 3 minutes. After 3 minutes of coolant circulation, the temperature of each zone remained stable, and the discrete value remained at a low level. This not only ensured the dewaxing effect, but also avoided energy waste caused by overcooling, achieving efficient energy utilization.

[0149] During dewaxing of a ceramic plate, temperature variations vary across zones due to the amount and distribution of residual wax. Calculating the discrete values ​​of the zone temperature data and comparing them with a reference discrete value effectively assesses the temperature uniformity across the plate. When the zone discrete value exceeds the reference discrete value, the coolant circulation component activates and adjusts its operating time based on the discrete difference to remove heat and balance the temperatures across the zones. If certain zones overheat due to excess wax residue and high heating power, the coolant circulation system accelerates heat dissipation, bringing the temperatures across the zones closer to a uniform level. This prevents dewaxing quality issues caused by localized overheating or overcooling, and provides a stable temperature environment for the wafer. Accurate temperature control is crucial for effective dewaxing. Independent zone temperature control allows precise heating based on the amount of residual wax, while coolant circulation control based on the temperature discrete value prevents incomplete dewaxing or carbonization of the wax layer caused by localized temperature variations. For example, if some areas have less residual wax and experience a rapid temperature rise, the coolant circulation assembly can dissipate heat promptly to prevent overheating in these areas. Meanwhile, areas with more residual wax can continue to be heated appropriately to ensure complete melting, thereby improving overall dewaxing efficiency and increasing wafer yield. Monitoring the discrete values ​​of each zone and rationally controlling the operating hours of the coolant circulation assembly can avoid unnecessary energy consumption. When the discrete values ​​are close to or less than the reference discrete value, indicating relatively uniform temperatures across zones, the operating hours of the coolant circulation assembly can be shortened to reduce energy consumption. When temperature variations are significant, the operating hours can be extended to ensure uniform temperatures. This ensures efficient energy utilization and reduces production costs while maintaining dewaxing process quality. Sustained localized high temperatures not only impair dewaxing efficiency but can also damage the ceramic plate and wafer. This method promptly adjusts the temperature of each zone to avoid increased thermal stress on the equipment and changes in wafer physical properties caused by excessive temperatures, extending equipment life, reducing maintenance costs, and ensuring wafer quality and performance.

[0150] In order to further improve the control of the temperature uniformity of the ceramic disk, the method further includes the following steps:

[0151] The heating controller continuously collects zone temperature data from the infrared temperature sensors corresponding to each sensing zone 5. For multiple adjacent sensing zones 5, the temperature difference between them is calculated, resulting in multiple temperature difference values. This step accurately captures the temperature variations between adjacent areas of the ceramic disk, providing basic data for subsequent analysis of temperature unevenness.

[0152] After obtaining multiple temperature differences, the heating controller uses statistical methods to calculate the discrete values ​​of these temperature differences, which are defined as the difference discrete value. The difference discrete value quantifies the degree of uneven temperature distribution on the surface of the ceramic disk. A larger discrete value indicates a more unstable temperature difference between adjacent zones and a more uneven temperature distribution; conversely, a smaller discrete value indicates a relatively uniform temperature distribution.

[0153] The heating controller adjusts the operating speed of the circulation pump in a positive correlation based on the calculated discrete difference value. Specifically, when the discrete difference value is large, indicating a significant temperature difference between adjacent zones, the operating speed of the circulation pump is increased, accelerating the circulation of the coolant in the heat dissipation microchannel 4, enhancing the heat dissipation effect, allowing heat to transfer more quickly from high-temperature areas to low-temperature areas, and promoting temperature balance. When the discrete difference value is small, indicating a relatively uniform temperature distribution, the operating speed of the circulation pump is reduced to avoid excessive heat dissipation and reduce energy consumption.

[0154] For example, the ceramic disk is divided into six sector-shaped sensing zones 5, labeled P1, P2, P3, P4, P5, and P6. Each zone is equipped with a dedicated alternating magnetic field generator and infrared temperature sensor, and the disk body is equipped with heat dissipation microchannels 4 connected to the coolant circulation system.

[0155] Initial Dewaxing: Large Temperature Variations: At the beginning of the dewaxing process, the temperature differences between zones were significant due to varying amounts of residual wax. The temperature difference between P1 and P2 was 12°C, 8°C between P2 and P3, 15°C between P3 and P4, 10°C between P4 and P5, 9°C between P5 and P6, and 13°C between P6 and P1. Statistically calculated, the discrete value of these temperature differences was 3.5°C, a large value indicating unstable temperature differences between adjacent zones and uneven temperature distribution. Based on this discrete value, the heating controller increased the circulation pump speed from the initial 800 rpm to 1500 rpm. The high-speed circulation of the coolant accelerated heat transfer, allowing heat from high-temperature areas (such as P3) to flow rapidly to cooler areas, promoting temperature uniformity across the zones.

[0156] Mid-stage dewaxing: Temperatures become more uniform: As dewaxing progresses, the wax layers in each zone gradually melt, and temperature differences decrease. At this point, the temperature difference between P1 and P2 is 4°C, P2 and P3 is 3°C, P3 and P4 is 5°C, P4 and P5 is 3°C, P5 and P6 is 2°C, and P6 and P1 is 4°C. Recalculating the discrete values ​​of the temperature differences reveals a value of 1.2°C, a significant decrease from the initial stage, indicating that the temperature distribution between adjacent zones is becoming more uniform. The heating controller reduces the circulation pump speed to 1000 rpm to prevent excessive heat dissipation and reduce energy consumption.

[0157] Late-stage dewaxing: Temperatures are essentially balanced: By the end of dewaxing, the wax layer in each zone has been largely removed, and temperatures are essentially uniform. The temperature difference between P1 and P2 is 1°C, P2 and P3 is 0.5°C, P3 and P4 is 1.2°C, P4 and P5 is 0.8°C, P5 and P6 is 0.6°C, and P6 and P1 is 1°C. The calculated discrete value of the temperature difference is 0.3°C, a very small value, indicating a very uniform temperature distribution between adjacent zones. The heating controller further reduces the circulation pump speed to 600 rpm to maintain heat dissipation while minimizing energy consumption.

[0158] During the scraper dewaxing process, the uneven distribution of wax residue causes the temperature changes of each partition of the ceramic disk to be asynchronous. By calculating the temperature difference between adjacent partitions and the discrete value of the difference, the temperature abnormality area can be accurately located. When the discrete value of the temperature difference between adjacent partitions is large, it means that the temperature distribution of these areas is extremely unstable. At this time, increasing the speed of the circulation pump can quickly enhance the heat dissipation effect, promote the flow of heat from the high-temperature area to the low-temperature area, and prevent problems such as insufficient melting of the wax layer and damage to the wafer due to local overheating or overcooling, thereby ensuring the smooth progress of the scraper dewaxing process and greatly reducing the defective rate. Different semiconductor manufacturing processes have different requirements for the temperature uniformity of ceramic disks. This control method based on the discrete value of the difference can flexibly adjust the speed of the circulation pump according to the actual temperature distribution, so that the ceramic disk can quickly adapt to various process requirements and provide a stable and reliable temperature environment for different process links.

[0159] When the discrete value of the difference is small, it indicates that the temperature distribution of the ceramic disk is relatively uniform. At this time, reducing the speed of the circulation pump can avoid the energy waste caused by excessive circulation of the coolant, and effectively reduce energy consumption while ensuring temperature uniformity. For example, in the later stage of the scraper dewaxing process, as the wax layer is gradually removed, the temperature of each partition tends to be balanced. By reducing the speed of the circulation pump, unnecessary energy consumption can be significantly reduced, and production costs can be reduced. Compared with the traditional fixed-speed circulation pump control method, the dynamic adjustment of the circulation pump speed based on the discrete value of the difference can accurately control the heat dissipation intensity according to the real-time temperature distribution of the ceramic disk, realize the reasonable allocation of heat dissipation resources, and avoid unreasonable energy consumption.

[0160] Uneven temperature distribution on the ceramic disc can cause significant thermal stress on equipment components, which can lead to deformation and damage over time. Precisely controlling the circulation pump speed and balancing the temperature across the ceramic disc effectively reduces thermal stress, extending the life of key components such as the disc, electromagnetic induction layer 2, and cooling system, and reducing maintenance and replacement costs. A stable temperature environment helps maintain the performance of all equipment components, reduces interference with equipment operation caused by temperature fluctuations, ensures long-term stable operation, and improves the continuity and reliability of the production process.

[0161] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A temperature control method for a ceramic plate for attaching wafers, characterized in that: Based on a ceramic substrate (1), an induction groove is provided in the ceramic substrate (1), and an electromagnetic induction layer (2) is embedded in the induction groove; an insulating layer (3) is provided on the surface of the electromagnetic induction layer (2); an electromagnetic heating component is provided corresponding to the electromagnetic induction layer (2); the electromagnetic heating component includes a heating controller, an alternating magnetic field generator and an infrared temperature sensor, and the heating controller is electrically connected to the alternating magnetic field generator and the infrared temperature sensor; The front side of the ceramic substrate (1) is an attachment surface, and the back side of the ceramic substrate (1) is provided with a heat dissipation microchannel (4), the heat dissipation microchannel (4) is connected to a coolant circulation component, the coolant circulation component includes a cooling controller, a circulation pump and a water temperature sensor, and the cooling controller is electrically connected to the circulation pump and the water temperature sensor; The method comprises the following steps: The heating controller obtains infrared temperature data from the infrared temperature sensor; Calculating a first temperature difference between the infrared temperature data and preset heating reference temperature data; adjusting the operating power of the alternating magnetic field generator in a positive correlation with the first temperature difference; the greater the first temperature difference, the greater the operating power of the alternating magnetic field generator; and the smaller the first temperature difference, the smaller the operating power of the alternating magnetic field generator; The cooling controller obtains water temperature data from the water temperature sensor; Calculating a second temperature difference between the water temperature data and a preset cooling reference temperature data; adjusting the operating power of the circulation pump in a positive correlation with the second temperature difference; The larger the second temperature difference is, the greater the operating power of the circulating pump is; The smaller the second temperature difference is, the smaller the operating power of the circulating pump is; The electromagnetic induction layer (2) has a plurality of induction partitions (5), each of the induction partitions (5) corresponds one-to-one to the alternating magnetic field generator, and each of the induction partitions (5) corresponds one-to-one to the infrared temperature sensor; The method further comprises the steps of: The heating controller controls and connects a plurality of the alternating magnetic field generators and a plurality of the infrared temperature sensors; The heating controller controls all the alternating magnetic field generators to heat the induction partitions (5) at a set test power for a preset test duration, and obtains partition temperature data of each of the induction partitions (5) through the corresponding infrared temperature sensor; According to the difference between the partition temperature data and the corresponding preset test temperature data, the adjustment gain value of the working power of the alternating magnetic field generator corresponding to the partition temperature data is anti-correlatedly adjusted; the larger the difference, the smaller the corresponding adjustment gain value of the working power of the alternating magnetic field generator; the smaller the difference, the larger the corresponding adjustment gain value of the working power of the alternating magnetic field generator.

2. The temperature control method for a ceramic plate for attaching wafers according to claim 1, characterized in that: The method further comprises the steps of: The heating controller controls and connects a plurality of the alternating magnetic field generators and a plurality of the infrared temperature sensors; The heating controller controls all the alternating magnetic field generators to heat the induction partitions (5) at a set test power for a preset test duration, and obtains partition temperature data of each of the induction partitions (5) through the corresponding infrared temperature sensor; According to the difference between the partition temperature data and the corresponding preset test temperature data, the opening phase angle of the alternating magnetic field generator corresponding to the partition temperature data is positively correlated and adjusted; the larger the difference, the larger the corresponding opening phase angle of the alternating magnetic field generator; the smaller the difference, the smaller the corresponding opening phase angle of the alternating magnetic field generator.

3. The temperature control method for a ceramic plate for attaching wafers according to claim 1, characterized in that: The method further comprises the steps of: Calculate the discrete values ​​of the plurality of partition temperature data as partition discrete values; If the partition discrete value is greater than a preset reference discrete value, the coolant circulation component is started and continues to run for a preset working time, and the difference between the partition discrete value and the reference discrete value is calculated as a discrete difference; Adjust the value of the working time according to the positive correlation of the discrete difference; The larger the discrete difference is, the longer the working time is; The smaller the discrete difference is, the larger the value of the working time is.

4. The temperature control method for a ceramic plate for attaching wafers according to claim 3, characterized in that: The method further comprises the steps of: Calculating the difference between the temperature data of a plurality of adjacent partitions to obtain a plurality of temperature difference values; Calculate the discrete values ​​of the plurality of temperature differences as difference discrete values; The operating speed of the circulation pump is adjusted according to the positive correlation of the difference discrete value; the larger the difference discrete value, the greater the operating speed of the circulation pump; the smaller the difference discrete value, the smaller the operating speed of the circulation pump.

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