Double-sided polishing system and method with integrated temperature compensation

Abstract

The invention provides a double-sided polishing system and method with an integrated temperature compensation function. The system comprises a lower fixed disc and an upper fixed disc. The bearing disc is arranged between the lower fixed disc and the upper fixed disc, a plurality of wafer bearing holes are formed in the bearing disc, and the bearing disc is configured to move relative to the lower fixed disc and the upper fixed disc in the polishing process; the plurality of thermal management assemblies are integrated in the bearing plate, and are arranged in one-to-one correspondence with the plurality of wafer bearing holes; and the main controller is in communication connection with the plurality of thermal management assemblies, and the main controller is configured to independently control each of the plurality of thermal management assemblies in the polishing process, so that the plurality of wafer bearing holes are constantly kept at respective target temperatures.

Description

Technical Field

[0001] This disclosure relates to the field of semiconductor manufacturing technology, and in particular to a double-sided polishing system and method with integrated temperature compensation. Background Technology

[0002] In advanced semiconductor integrated circuit manufacturing, the surface morphology of silicon wafers is crucial for subsequent photolithography processes and device yield. Chemical mechanical polishing (CMP) is currently the only critical process capable of simultaneously achieving global and local high flatness of the wafer surface. Double-side polishing (DSP), an important form of CMP, applies pressure and chemical-mechanical action to both the front and back sides of the wafer using upper and lower polishing pads (i.e., upper and lower fixed pads). This aims to efficiently remove surface and subsurface damage layers remaining from previous processes such as wire cutting and grinding, and to achieve nanometer-level surface roughness and extremely high standards of global flatness, such as total thickness variation (TTV).

[0003] In conventional double-sided polishing processes, batch processing is typically employed. For example, multiple wafers (e.g., 5, 10, or 15) are simultaneously loaded onto the polishing pad of a double-sided polishing machine for synchronous processing. Throughout the polishing process, the machine typically relies on integrated thickness sensors (e.g., average thickness sensors) to monitor the thickness of the batch of wafers in real time and calculate an average value. When this average thickness reaches the pre-set processing endpoint, the machine stops processing all wafers. The industry has recognized that a significant factor influencing and limiting the final flatness is the initial state variation of the incoming wafers. To address this issue, incoming wafers are sorted and grouped according to pre-set parameters before polishing. Pre-sorting based on geometric parameters ensures that wafers processed within the same batch have similar initial geometric shapes, thereby aiming to achieve more uniform processing results.

[0004] However, the proposed "grouping by geometric parameters" scheme fails to address (or even identify) a more challenging technical problem in actual production that has a greater impact on flatness—the uneven removal rate and flatness degradation caused by "mixing" processing. Here, "mixing" refers to the mixing of wafers from different wafer transfer boxes or different production batches in the same double-sided polishing process during actual production scheduling. The limitation of the above scheme is that the "geometric parameters" it relies on do not reflect the "inherent material properties" of the wafer. Summary of the Invention

[0005] This disclosure provides a double-sided polishing system and method with integrated temperature compensation, which can solve the problem of uneven removal rate within a batch due to different wafer hardness / resistance in double-sided polishing "mixed material" processing, which leads to deterioration of flatness.

[0006] The technical solution disclosed herein is implemented as follows: In a first aspect, this disclosure provides a double-sided polishing system with integrated temperature compensation, the system comprising: Lower and upper plate positions; A carrier disk is disposed between the lower fixed disk and the upper fixed disk, the carrier disk has a plurality of wafer carrier holes, and the carrier disk is configured to move relative to the lower fixed disk and the upper fixed disk during the polishing process; The system further includes: Multiple thermal management components are integrated into the carrier disk and are respectively disposed in correspondence with the multiple wafer carrier vias; and The main controller is communicatively connected to the plurality of thermal management components. The main controller is configured to independently control each of the plurality of thermal management components during the polishing process so that the plurality of wafer carrier holes are kept constant at their respective target temperatures.

[0007] In a second aspect, this disclosure provides a double-sided polishing method with integrated temperature compensation, using the double-sided polishing system with integrated temperature compensation according to the first aspect, the method comprising: Multiple wafers are loaded in the plurality of wafer carrier holes; Obtain the resistance value of each wafer in the plurality of wafer carrier holes; Based on the resistance value of each wafer, the main controller determines the target temperature corresponding to each of the plurality of wafer carrier holes; Initiating the polishing process causes the carrier disk to move relative to the lower fixed disk and the upper fixed disk; and During the polishing process, the main controller independently controls the plurality of thermal management components integrated in the carrier disk to keep the plurality of wafer carrier holes constant at their respective target temperatures.

[0008] By integrating thermal management components into the moving carrier disk and corresponding them one-to-one with the carrier holes, the fundamental challenge of balancing planetary motion mechanical constraints and differentiated temperature control in double-sided polishing equipment is solved. This solution enables the temperature control actuator to be geometrically locked to the wafer and accompany it throughout the process, while embedding the timing of temperature control into the main process flow, eliminating heat transfer losses from the pretreatment process, and achieving real-time coupling between the temperature field and the chemical-mechanical interaction field. The main controller's independent drive architecture for multiple thermal management components allows the system to execute opposing operations in parallel—heating low-resistivity hard wafers to exponentially increase the chemical etching rate, and actively cooling high-resistivity soft wafers to combat frictional heat, compressing temperature steady-state errors, improving response speed, reducing the difference in the total wafer removal rate within a batch, and ultimately improving the total thickness deviation. This non-contact control design avoids the risks of slip ring wear and contamination, increases the mean time between failures (MTBF), and provides the ability to dynamically adjust the target temperature online during the process. Its distributed intelligent control architecture also reserves expansion interfaces for the integration of multi-physics sensors and adaptive polishing systems, completing a logical closed-loop elimination of the flatness deterioration problem caused by material mixing, from structural innovation to... Attached Figure Description

[0009] Figure 1 This is a schematic structural diagram of a double-sided polishing system according to an embodiment of the present invention, showing the structural relationship between the lower mounting plate, the wafer carrier plate, and the upper mounting plate.

[0010] Figure 2 for Figure 1 A top-down kinematic view of the double-sided polishing system, illustrating the planetary motion of the wafer carrier disk relative to the lower fixed disk, as well as the central gear and the outer gear ring.

[0011] Figure 3 This is a schematic diagram of the system architecture of an embodiment of the present invention, showing the wireless power transmission circuit, the "intelligent" carrier disk, and the main controller in the lower plate.

[0012] Figure 4 for Figure 3 A three-dimensional magnified schematic diagram of a single wafer carrier hole in the "intelligent" carrier disk shows the integrated structure of the thermal management components, as well as the temperature sensor, wireless power receiving circuit, and control module.

[0013] Figure 5 for Figure 3 An enlarged cross-sectional schematic diagram of a single wafer carrier hole in the "intelligent" carrier disk shows the integrated structure of an optional thermal management component, namely a flexible thin-film heater.

[0014] Figure 6 This is a flowchart of a method according to an embodiment of the present invention. Detailed Implementation

[0015] The technical solutions in this disclosure will now be clearly and completely described with reference to the accompanying drawings.

[0016] The inherent material properties of wafers (such as hardness) have a decisive impact on the removal rate of double-sided polishing, and this property can be characterized by the electrical parameter "resistivity" (Res): the higher the doping concentration, the lower the wafer resistance, and the higher the hardness of the wafer (ingot). When "mixing" occurs in the double-sided polishing process (for example, in a batch of 15 wafers, there are both high-resistivity "soft" wafers and low-resistivity "hard" wafers), and constant processing parameters (for example, a constant processing temperature of 23°C) are used in existing technology, the mechanical removal rate of wafers with higher hardness (low resistance) will inevitably be significantly lower. This makes the overall removal rate of "hard" wafers (low resistance) much lower than that of "soft" wafers (high resistance). Ultimately, when the "thickness average" sensor reading on which the equipment relies reaches the processing endpoint, the "hard" wafers (low resistance) with slower removal rates are actually severely underpolished, resulting in extremely poor thickness uniformity within the batch, and ultimately leading to a severe deterioration in wafer flatness. Therefore, existing geometric grouping schemes cannot solve the problem of "uneven removal rate" caused by different material hardness.

[0017] The core objective of this invention addresses the aforementioned problem: the uneven removal rate in double-sided polishing "mixed material" processing due to differences in the inherent properties of wafer materials (i.e., hardness determined by doping concentration, which can be characterized by resistance). The core idea of ​​this invention is that, since low-resistivity (high-hardness) wafers have a lower "mechanical removal rate," increasing their processing temperature selectively enhances their "chemical removal rate" (i.e., polishing slurry activity), thereby compensating for the lack of "mechanical removal rate" and ensuring that wafers with different resistances exhibit a more consistent "total removal rate" in the same batch of processing.

[0018] However, the biggest obstacle to realizing this approach lies in the mechanical structure of standard double-sided polishing equipment. First, refer to... Figure 1 and Figure 2This section clarifies the standard structure. A standard double-sided polishing system comprises a lower platen 100 and an upper platen 300 as its core components. The lower platen 100 and upper platen 300 are typically large, flat discs with polishing pads (not shown) attached to their surfaces. The system also includes at least one (typically five) separate carrier plates 200 for holding the wafers. These carrier plates 200 are also commonly referred to as "planetary gears" or "carriers." The carrier plate 200 is a thin disc typically made of engineering plastics, composite materials, or high-performance polymers. The carrier plate 200 has multiple (typically three) through-holes, or wafer carrier holes 210, for accommodating the wafers. During polishing, the carrier plate 200, carrying the wafers, is "clamped" between the polishing pads of the lower platen 100 and the upper platen 300. Figure 2 As shown, double-sided polishing equipment typically also includes a central "sun gear" and a peripheral "internal ring gear" (teeth not shown). The outer edge of the carrier disk 200 is typically toothed, meshing with the sun gear and / or the internal ring gear. As the lower carrier disk 100 and the upper carrier disk 300 rotate, the gear mechanism drives the carrier disk 200 to perform complex planetary motions on the surface of the lower carrier disk 100. These planetary motions include the "rotation" of the carrier disk 200 about its own central axis and the "revolution" of the carrier disk 200 about the central axis of the lower carrier disk 100. This mechanical structure results in continuous, high-speed, and complex relative motion between the carrier disk 200 (and the wafer carrier aperture 210 thereon) and the lower carrier disk 100. This fact renders any attempt to install a thermal management component in a fixed position on the lower carrier disk 100 and expect it to continuously and independently control the temperature of a particular wafer during the polishing process (i.e., in motion) infeasible. This invention provides two distinct but both feasible implementations to overcome this mechanical constraint in order to achieve the aforementioned differentiated temperature compensation.

[0019] To overcome the technical challenges posed by planetary motion, the present invention provides a preferred embodiment, which refers to... Figures 3 to 5 The following description is provided. This solution offers an "in-situ" compensation system, the core idea of ​​which is to transform the carrier plate 200 from a traditional "passive" mechanical component into an "intelligent" carrier plate integrating electronic, sensing, and thermal management functions. For example... Figure 3 As shown, the "intelligent" carrier plate 200 is designed to be able to move between the lower plate 100 and the upper plate 300 (e.g., Figure 2 (As shown) planetary motion, while interacting with external control systems and wireless power transmission systems in a non-contact manner.

[0020] Reference Figure 4 (A cross-section of a single wafer carrier aperture 210 is shown.) The "smart" carrier disk 200 integrates several key components within its disk body or on its surface. First, an independently controllable in-situ thermal management component 220 is integrated at or near the sidewall of each wafer carrier aperture 210. This thermal management component 220 is positioned one-to-one with each wafer carrier aperture 210. In a preferred embodiment of the invention, the thermal management component 220 is a miniature thermoelectric cooler (TEC), also known as a Peltier device. Choosing a thermoelectric cooler offers several technical advantages. First, thermoelectric coolers are purely solid-state devices with no moving parts, allowing them to be manufactured very small (e.g., miniature thermoelectric cooler modules), making them ideal for embedding into the disk body of the carrier disk 200, adjacent to the wafer carrier apertures 210, without significantly increasing the thickness of the carrier disk 200 or compromising its mechanical structure. Furthermore, they exhibit extremely high reliability in the harsh environments of double-sided polishing processes with high mechanical stress, high vibration, and abrasive-laden surfaces.

[0021] Secondly, and most importantly, the thermoelectric cooler possesses bidirectional adjustment capability. The thermoelectric cooler operates based on the Peltier effect, consisting of an array of P-type and N-type semiconductor electrodes. When a direct current is applied, the movement of electrons and holes causes one ceramic surface (e.g., the cold side) to absorb heat, while the other (e.g., the hot side) releases heat. If the direction of the direct current is reversed, the hot and cold sides also reverse. This means that the same thermoelectric cooler can both actively heat and actively cool. This "active cooling" capability is crucial for implementing the compensation logic of this invention. The double-sided polishing process itself is a violent exothermic process. This frictional heat and the chemical reaction heat of the polishing fluid can cause the wafer's natural temperature (e.g., possibly reaching 30°C-40°C) to be much higher than the "reference temperature" (e.g., 23°C) expected in this invention (e.g., for "soft" wafers). In this case, if the thermal management component 220 is merely a heater (e.g., ... Figure 5The alternative thin-film heater 222 shown will not be able to achieve the target temperature of 23°C. However, the thermoelectric cooler in this embodiment, under the command of the main controller 130, can operate in reverse (i.e., enter cooling mode), that is, its cold side faces the wafer carrier hole 210, actively "pumping" away the heat (including frictional heat) at the wafer carrier hole 210, thereby forcibly and precisely lowering the temperature of the "soft" wafer from the high frictional temperature (e.g., 30°C) and maintaining it constant at 23°C. Simultaneously, for the "hard" wafer (low resistance), it can operate in the forward mode (heating mode), heating it and maintaining it constant at (e.g.) 27°C.

[0022] To achieve the cooling function of a thermoelectric cooler, thermodynamics requires that its "hot side" (i.e., the side that releases heat in cooling mode) must be able to effectively dissipate heat. In the design of the "intelligent" support plate 200, where space is extremely limited and fans or water-cooling pipes cannot be installed, this invention provides a preferred heat dissipation solution: such as... Figure 4 As shown, the hot side of the thermoelectric cooler is designed to achieve good thermal coupling with the disk body of the support disk 200 (e.g., a metal or high thermal conductivity composite matrix). Thus, the disk body of the support disk 200, with its large heat capacity and large contact surface area when moving in the polishing slurry, acts as a passive radiator for the heat pumped by the thermoelectric cooler in cooling mode, dissipating heat into the polishing environment.

[0023] like Figure 5 As shown, in a simpler and less expensive alternative implementation, if the application does not require active cooling (e.g., the reference temperature is higher than the friction temperature, or only heating compensation is needed), the thermal management component 220 can be implemented as a flexible thin-film heater 222. This thin-film heater 222 typically consists of a flexible substrate (e.g., polyimide) and resistance heating traces (e.g., nickel-chromium alloy) deposited on the substrate. The advantage of this thin-film heater 222 is its extremely thin thickness, allowing it to be easily laminated or adhered to, for example, the sidewalls or vicinity of the wafer carrier via 210, exhibiting excellent thermal response speed and uniformity.

[0024] To achieve precise closed-loop control of the thermoelectric cooler (or thin-film heater 222), such as Figure 4 and Figure 5 As shown, a temperature sensor 228 is also integrated near each wafer carrier via 210. This temperature sensor 228 is preferably a miniature, fast-response type, such as a miniature platinum resistance thermometer or a thermistor. These temperature sensors 228 are designed to operate reliably in harsh environments (high pressure, chemical corrosion, vibration) where both sides are polished, and their measuring endpoints are positioned as close as possible to the wafer (not shown) to provide real-time, high-precision temperature feedback for forming a closed-loop temperature control.

[0025] The first core challenge faced by the first embodiment of the present invention is how to provide continuous and reliable power to all the electronic components integrated on the moving "intelligent" carrier disk 200 (e.g., 15 thermoelectric coolers, 15 temperature sensors 228, and control module 230). Since thermoelectric coolers are high-power devices when cooling or heating, battery-based solutions are not feasible due to capacity, lifespan, safety, and replacement issues. This embodiment employs a novel Wireless Power Transfer (WPT) scheme, specifically, preferably Inductive Power Transfer (IPT).

[0026] Reference Figure 3 and Figure 4 The wireless power transmission system comprises two parts. The first part is a wireless power transmitting circuit 140, which consists of one or more primary coils permanently embedded or integrated within the body of the lower plate 100 of the double-sided polishing system. The second part is a wireless power receiving circuit 240, which consists of one or more secondary coils correspondingly embedded within the body of the moving "intelligent" carrier plate 200. During polishing, the wireless power transmitting circuit 140 in the lower plate 100 is activated, generating a high-frequency, time-varying alternating magnetic field. As the "intelligent" carrier plate 200 performs planetary motion above the lower plate 100, its internal wireless power receiving circuit 240 continuously "sweeps" and cuts through this magnetic field, inducing an AC voltage in the wireless power receiving circuit 240 based on the principle of electromagnetic induction. This contactless energy transmission method fundamentally eliminates the mechanical wear, corrosion, poor contact, and sparking problems inherent in traditional contact-based solutions such as slip rings or brushes.

[0027] This invention further solves the technical challenge of achieving wireless power transmission in the harsh environment of double-sided polishing. Firstly, to address the problem of constantly changing relative positions and coupling coefficients between the transmitting coil of the wireless power transmitting circuit 140 and the receiving coil of the wireless power receiving circuit 240 due to planetary motion, preferably, the wireless power transmitting circuit 140 is not a single coil, but rather includes an array of transmitting coils, such as multiple coils arranged in a honeycomb or matrix pattern, covering the entire planetary motion path of the carrier disk 200. The main controller 130 can dynamically and selectively activate the coils below the current location of the wafer carrier aperture 210 of the carrier disk 200, thereby ensuring that the wireless power receiving circuit 240 receives a stable and continuous power supply regardless of its movement.

[0028] Secondly, wireless power transmission / inductively coupled power transmission systems typically operate at high frequencies (e.g., in the kHz range). To overcome the "skin effect" and "proximity effect" caused by high-frequency alternating current in ordinary copper wires (which lead to a sharp increase in resistance and a decrease in efficiency), preferably, the transmitting coil of the wireless power transmitting circuit 140 and / or the receiving coil of the wireless power receiving circuit 240 are wound with Litzwire. Litzwire is made of multiple strands (e.g., hundreds of strands) of mutually insulated, extremely fine copper wires twisted together, which allows the current to be evenly distributed across the entire conductor cross-section, rather than just on the surface, thereby greatly reducing high-frequency AC resistance and improving the energy transmission efficiency of the wireless power transmission system.

[0029] Secondly, the substrate of the lower platen 100 is typically metal (e.g., stainless steel). If the alternating magnetic field of the wireless power transmitting circuit 140 is directly coupled into the metal substrate of the lower platen 100, huge eddy currents will be induced. These eddy currents not only cause severe energy loss but also cause abnormal heating of the lower platen 100, thereby interfering with the precision temperature control objective of this invention. To solve this problem, this invention preferably further includes a ferrite shielding layer. This ferrite shielding layer is disposed between the transmitting coil of the wireless power transmitting circuit 140 and the metal substrate of the lower platen 100, and / or, between the receiving coil of the wireless power receiving circuit 240 and the substrate of the carrier plate 200. As a high-permeability material, ferrite provides a low-resistivity path for magnetic field lines, confining them between the transmitting coil of the wireless power transmitting circuit 140 and the receiving coil of the wireless power receiving circuit 240, thereby preventing the magnetic field from leaking into the metal substrate and generating eddy currents, greatly improving system efficiency and safety.

[0030] The wireless power receiving circuit 240 senses a high-frequency alternating current on the carrier disk 200, which may fluctuate with movement. For example... Figure 4 As shown, this energy is fed to a control module 230 integrated on the carrier disk 200. The control module 230 integrates a power management unit, which includes a high-efficiency rectifier circuit (e.g., an active synchronous rectifier to reduce diode voltage drop losses) and a voltage regulator circuit. This power management unit converts the received AC power into stable, clean DC power (e.g., 5V, 12V, or 24V) to power all the high-power thermal management components 220, temperature sensors 228, and microcontrollers (MCUs) on the carrier disk 200.

[0031] The second core challenge faced by the first embodiment of the present invention is how the main controller 130, located outside the device, communicates with the moving "intelligent" carrier plate 200. That is, how the main controller 130 sends (for example) 15 different target temperatures (setpoints) to the carrier plate 200, and how the carrier plate 200 transmits the real-time temperatures (feedback values) of 15 temperature sensors 228 back to the main controller 130.

[0032] Combination Figure 4 This embodiment employs a two-way wireless data communication scheme. The system includes a control module 230 integrated on the "intelligent" carrier disk 200. This control module 230 is the "brain" of the carrier disk 200, its core being a microcontroller and integrating an onboard wireless transceiver. The control module 230 is electrically connected to all thermal management components 220 and temperature sensors 228 via internal circuitry (e.g., a PCB) within the carrier disk 200. The system also includes a main controller 130 located in a stationary external part of the device, which is connected to a base station wireless transceiver. A two-way wireless data link is established between the main controller 130 and the onboard control module 230 via radio frequency signals.

[0033] This invention further solves the technical challenge of achieving wireless communication in the harsh environment of double-sided polishing. The cavity of the double-sided polishing equipment is a large metal cavity resistor, whose metal walls strongly shield, reflect, and attenuate RF signals. Simultaneously, the high-frequency magnetic field of the wireless power transmitting circuit 140 and the operation of the motor generate strong electromagnetic interference.

[0034] To achieve reliable wireless communication within a highly electromagnetically interfered, strongly shielded metal cavity, this invention provides a preferred communication protocol: Bluetooth Low Energy (BLE). The key reason for choosing BLE is its Adaptive Frequency Hopping (AFH) mechanism. BLE operates in the 2.4 GHz band. Its AFH mechanism enables the control module 230 to detect electromagnetic interference of specific frequencies generated by the wireless power transmitting circuit 140 or the motor in real time, and dynamically and intelligently "hop" to an undisturbed "clean" channel for data packet transmission and reception. This interference avoidance capability makes it highly robust in congested industrial environments. Furthermore, the low power consumption of BLE is crucial for the control module 230, which is powered by the wireless power receiving circuit 240.

[0035] The control logic of this invention is a "distributed" control architecture. This architecture distributes control tasks to the main controller 130 and the onboard control module 230.

[0036] The main controller 130 acts as the "global" brain, responsible for executing non-real-time, high-level decision-making tasks. Specifically, the main controller 130 is configured to communicate with the factory's manufacturing execution system via Ethernet or other means before the process begins, automatically obtaining the unique IDs and corresponding resistance values ​​of the 15 wafers to be loaded into the 15 wafer carrier vias 210. Next, the main controller 130 queries its internally stored resistance-temperature compensation relationship. This relationship is preferably implemented as a look-up table (LUT). In an exemplary but non-limiting implementation, the compensation relationship can be defined as follows: a reference temperature of 23.0°C is used as the reference for wafer resistance values ​​above 18.0 Ω·cm (high resistance, wafer); the target temperature is set to 24.0°C when the resistance value is in the range of 16.0 to 17.9 Ω·cm; the target temperature is set to 25.0°C when the resistance value is in the range of 14.0 to 15.9 Ω·cm; the target temperature is set to 27.0°C when the resistance value is in the range of 12.0 to 13.9 Ω·cm; and the target temperature is set to 27.0°C or a higher compensation value (e.g., not higher than the slurry stability of 32°C) when the resistance value is below 12.0 Ω·cm (low resistance, wafer). The main controller 130 then sends a list of these 15 target temperature setpoints to the "intelligent" carrier disk 200 via a base station wireless transceiver. Finally, during the process, the main controller 130 continuously receives 15 real-time temperature data points wirelessly transmitted from the carrier plate 200 for global monitoring, data recording, and (optionally) dynamic adjustment of the target temperature.

[0037] The onboard control module 230 acts as a "local" executor, responsible for performing real-time, high-speed closed-loop control tasks. Specifically, the control module 230 is configured to receive and store 15 target temperatures (setpoints) from the main controller 130. Then, the control module 230 runs 15 independent PID (proportional-integral-derivative) closed-loop control algorithms locally and in parallel.

[0038] Taking wafer carrier via 210 (number 11) as an example, its local PID loop is as follows. The target value (Setpoint, SP) of control module 230 is 27.0°C. Control module 230 reads the real-time feedback value (Process Variable, PV) of temperature sensor 228 (number 11) at a high frequency (e.g., 100 times per second) (e.g., PV = 26.8°C). The PID algorithm calculates the current error (Error = SP - PV = +0.2°C). The PID algorithm calculates a control output value based on its proportional (P), integral (I, used to accumulate historical errors to eliminate steady-state errors), and derivative (D, used to predict trends to suppress overshoot) gains. Control module 230 converts this control output value into a pulse-width modulated signal to drive the H-Bridge circuit. In this example, the H-Bridge is driven with a positive current to heat the thermal management component 220.

[0039] Taking wafer carrier via 210 (number 1) as an example: the target value (SP) is 23.0°C. Due to frictional heat generation, the feedback value (PV) of temperature sensor 228 (number 1) may be 24.1°C. The PID algorithm calculates the error (Error = SP - PV = -1.1°C). The PID algorithm calculates a control output value. The control module 230 drives the H-bridge circuit, applying a reverse current to cause its thermal management component 220 to actively cool, pulling the temperature back to 23.0°C.

[0040] The control module 230 periodically packages 15 PV values ​​and transmits them back to the main controller 130 via a wireless link.

[0041] This "distributed" control architecture (i.e., globally setting the target and using a local high-speed closed loop) is key to achieving high-precision, real-time, in-situ control. It avoids control oscillations or lags caused by the delay and instability of wireless communication, thus achieving the required goal of "constantly maintaining the target temperature".

[0042] The "intelligent" carrier plate 200 architecture invented in this embodiment of the invention—that is, integrating "local temperature sensor 228 + local thermal management component 220 + local control module 230 + wireless power receiving circuit 240 + wireless data" on a moving carrier plate 200—is significant far beyond temperature control. It essentially creates a universal, in-situ process monitoring platform. The control module 230 is a scalable system. Figure 4As shown, in addition to the temperature sensor 228 and the thermal management component 220, other types of additional in-situ sensors can be integrated at each wafer carrier via 210, and these additional in-situ sensors are connected to the control module 230 and powered by the wireless power receiving circuit 240.

[0043] See Figure 6 The present invention also provides a double-sided polishing method with integrated temperature compensation corresponding to the system of the above embodiments, the method comprising the following steps S601, S602, S603, S604 and S605.

[0044] S601: Loading multiple wafers in multiple wafer carrier holes.

[0045] S602: Obtain the resistance value of each wafer in multiple wafer carrier holes.

[0046] S603: Based on the resistance value of each wafer, the main controller determines the target temperature corresponding to each of the multiple wafer carrier holes.

[0047] S604: Start the polishing process by moving the carrier disc relative to the lower and upper fixed discs.

[0048] S605: During the polishing process, multiple thermal management components integrated in the carrier disk are independently controlled by the main controller to keep the multiple wafer carrier holes constant at their respective target temperatures.

[0049] More specifically, the method described above includes the following steps. Multiple wafers (e.g., a "mixed batch" with different resistance values) are loaded into multiple wafer carrier holes 210 of the "smart" carrier disk 200. The main controller 130 obtains the resistance values ​​of the batch of wafers from the factory's manufacturing execution system. The main controller 130 queries (as described above) a "resistance-temperature" compensation relationship (LUT) to determine individual target temperatures (e.g., 23°C, 25°C, 27°C) for each of the multiple wafer carrier holes 210. The main controller 130 transmits these target temperatures wirelessly to the control module 230 on the moving carrier disk 200. Double-sided polishing is initiated. The wireless power transmitting circuit 140 in the lower mounting disk 100 is activated, continuously providing wireless power to the wireless power receiving circuit 240 on the moving carrier disk 200 via wireless power transmission. The carrier disk 200 begins planetary motion. Throughout the motion and polishing process, the control module 230 on the carrier disk 200 continuously runs multiple independent local PID closed loops, utilizing the bidirectional adjustment capability (active heating or active cooling) of the thermal management component 220 to precisely and constantly maintain the multiple wafer carrier holes 210 at their respective target temperatures set by the main controller 130. Polishing stops when, for example, the average thickness reaches its endpoint.

[0050] This invention enables real-time, in-situ, independent, and closed-loop temperature control of each moving wafer throughout the entire polishing process. Its thermoelectric cooler's "active cooling" capability further allows the system to combat frictional heat during double-sided polishing, forcibly pulling down and maintaining the "soft" wafer at a reference temperature of 23°C. Furthermore, this "intelligent" carrier plate 200 integrates pressure and vibration sensors, providing unprecedented in-situ monitoring capabilities for each wafer in the double-sided polishing process.

[0051] In summary, both embodiments of the present invention can fundamentally solve the problem of uneven removal rate within a batch caused by "mixing", significantly improve wafer flatness (TTV), and increase product yield.

[0052] It should be noted that the technical solutions described in this disclosure can be combined arbitrarily as long as they do not conflict.

[0053] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A double-sided polishing system with integrated temperature compensation, the system comprising: Lower and upper plate positions; A carrier disk is disposed between the lower fixed disk and the upper fixed disk, the carrier disk has a plurality of wafer carrier holes, and the carrier disk is configured to move relative to the lower fixed disk and the upper fixed disk during the polishing process; The system is characterized in that it further comprises: Multiple thermal management components are integrated into the carrier disk and are respectively disposed in correspondence with the multiple wafer carrier vias; and The main controller is communicatively connected to the plurality of thermal management components. The main controller is configured to independently control each of the plurality of thermal management components during the polishing process so that the plurality of wafer carrier holes are kept constant at their respective target temperatures.

2. The double-sided polishing system with integrated temperature compensation according to claim 1, characterized in that, The main controller is configured to determine the target temperature of each of the plurality of wafer carrier holes based on the resistance value of the wafers loaded in the plurality of wafer carrier holes.

3. The double-sided polishing system with integrated temperature compensation according to claim 2, characterized in that, The main controller is configured to query a preset "resistance-temperature" compensation relationship stored in the main controller to determine the target temperature.

4. The double-sided polishing system with integrated temperature compensation according to claim 3, characterized in that, The "resistance-temperature" compensation relationship is defined as follows: with the reference temperature corresponding to the reference resistance value as the reference, for every preset decrease in the resistance value of the wafer, the target temperature increases by a preset temperature unit.

5. The double-sided polishing system with integrated temperature compensation according to claim 1, characterized in that, The system further includes: A wireless power transmitting circuit, said wireless power transmitting circuit being integrated into the lower plate; and A wireless power receiving circuit is integrated in the carrier disk and is configured to receive energy from the wireless power transmitting circuit and supply power to the plurality of thermal management components when the carrier disk moves.

6. The double-sided polishing system with integrated temperature compensation according to claim 5, characterized in that, The wireless power transmitting circuit and the wireless power receiving circuit are configured to transmit energy via inductive coupling.

7. The double-sided polishing system with integrated temperature compensation according to claim 6, characterized in that, The wireless power transmitting circuit includes a transmitting coil array arranged to cover the planetary motion path of the carrier disk.

8. The system according to claim 6, characterized in that, At least one of the coils of the wireless power transmitting circuit and the wireless power receiving circuit is wound using Litz wire.

9. A double-sided polishing method with integrated temperature compensation, characterized in that, Using the double-sided polishing system with integrated temperature compensation as described in any one of claims 1 to 8, the method comprises: Multiple wafers are loaded in the plurality of wafer carrier holes; Obtain the resistance value of each wafer in the plurality of wafer carrier holes; Based on the resistance value of each wafer, the main controller determines the target temperature corresponding to each of the plurality of wafer carrier holes; Initiating the polishing process causes the carrier disk to move relative to the lower fixed disk and the upper fixed disk; and During the polishing process, the main controller independently controls the plurality of thermal management components integrated in the carrier disk to keep the plurality of wafer carrier holes constant at their respective target temperatures.

10. The double-sided polishing method with integrated temperature compensation according to claim 9, characterized in that, The method of independently controlling the plurality of thermal management components integrated in the carrier disk via the main controller during the polishing process further includes: Continuous wireless power supply is provided to the wireless power receiving circuit in the carrier disk through the wireless power transmitting circuit; and The main controller communicates wirelessly with the control module on the carrier plate to send instructions for the target temperature and receive temperature feedback.

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