Method and apparatus for dynamically adjusting the moving speed of a heating plate in a pecvd process

Abstract

This application discloses a method and apparatus for dynamically adjusting the moving speed of a heating plate in a PECVD process, belonging to the field of plasma-enhanced chemical vapor deposition technology. The method includes: monitoring the real-time position of the heating plate within the reaction chamber, and determining the moving direction of the heating plate based on the real-time position and the target position; dynamically configuring a preset moving speed corresponding to the heating plate at its current real-time position based on the real-time position; and controlling the heating plate to move along the moving direction at the preset moving speed to the target position. This application achieves a dual improvement in wafer safety and process efficiency by employing a segmented speed dynamic adjustment strategy during the rising and falling phases of the heating plate, better adapting to the high-precision, high-yield semiconductor wafer PECVD deposition production requirements.

Description

Technical Field

[0001] This application relates to the field of plasma-enhanced chemical vapor deposition (PECVD) technology, and in particular to a method and apparatus for dynamically adjusting the moving speed of a heating plate in a PECVD process. Background Technology

[0002] In the PECVD (Plasma Enhanced Chemical Vapor Deposition) thin film deposition process for semiconductor wafers, the spacing between the heater and the showerhead is a key process parameter affecting the uniformity of plasma distribution, the film deposition rate, and the film quality. It directly determines the wafer deposition effect and yield. The moving speed of the heater directly affects the safe transport of the wafer and process stability, making it one of the core control parameters for the normal operation of the PECVD equipment. Currently, the existing technical solution in the industry is to adjust the spacing by moving the heater at a constant speed. This solution is widely used in various PECVD equipment and is the default spacing control method for mainstream PECVD equipment.

[0003] However, existing technologies have significant drawbacks and cannot meet the demands of high-precision, high-yield semiconductor mass production. The root cause lies in the fact that the uniform-speed movement mode cannot match the core requirements of different stages of the PECVD process. During the initial rising phase of the heating pad, the wafer rests on its surface solely due to gravity. If the speed is too high, relative sliding can easily occur between the wafer and the heating pad, causing the wafer to wobble or shift, thus affecting the uniformity of subsequent thin film deposition and even rendering the wafer unusable. Conversely, using a low-speed, uniform movement to avoid wobble significantly prolongs the heating pad's arrival time, reducing process efficiency and increasing production time and costs. Simultaneously, during PECVD deposition, the wafer surface generates static electricity due to plasma bombardment. After deposition, if the heating pad continues to descend rapidly at a uniform speed, the unreleased static electricity will create electrostatic attraction between the wafer and the heating pad, leading to uneven stress on the wafer and increasing the risk of wafer breakage. Summary of the Invention

[0004] To address the problem that existing technologies cannot balance wafer safety and process efficiency when adjusting the spacing of the heating plate at a constant speed, this application provides a method and apparatus for dynamically adjusting the moving speed of the heating plate in the PECVD process.

[0005] To achieve the above objectives, the first technical solution adopted in this application is: to provide a method for dynamically adjusting the moving speed of a heating plate in a PECVD process, which includes: monitoring the real-time position of the heating plate in the reaction chamber, and determining the moving direction of the heating plate based on the real-time position of the heating plate and the target position; dynamically configuring a preset moving speed corresponding to the current real-time position of the heating plate based on the real-time position; and controlling the heating plate to move to the target position along the moving direction at the preset moving speed.

[0006] The second technical solution adopted in this application is: providing a device for dynamically adjusting the moving speed of a heating plate in a PECVD process, comprising: a module for monitoring the real-time position of the heating plate in the reaction chamber and determining the moving direction of the heating plate based on the real-time position and the target position; a module for dynamically configuring a preset moving speed of the heating plate corresponding to its current real-time position based on the real-time position; and a module for controlling the heating plate to move to the target position along the moving direction at the preset moving speed.

[0007] The beneficial effects of the technical solution of this application are as follows: This application designs a method and device for dynamically adjusting the moving speed of the heating plate in the PECVD process. This method changes the way the heating plate moves at a constant speed to adjust the spacing. In the rising and falling stages of the heating plate, a segmented speed dynamic adjustment strategy is adopted to achieve a dual improvement in wafer safety and process efficiency, and better meet the needs of each stage of the PECVD process. At the same time, this application does not require large-scale equipment modification, effectively improves the uniformity of thin film deposition and wafer yield, and reduces the wafer breakage rate of the PECVD deposition process by more than 30%, which better adapts to the high-precision and high-yield semiconductor wafer PECVD deposition production needs. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0009] Figure 1 This is a flowchart illustrating a specific embodiment of a method for dynamically adjusting the moving speed of a heating plate in a PECVD process according to this application. Figure 2 This is a process flow diagram of a specific embodiment of a method for dynamically adjusting the moving speed of a heating plate in a PECVD process according to this application; Figure 3 This is a schematic diagram of a specific embodiment of a device for dynamically adjusting the moving speed of a heating plate in a PECVD process according to this application.

[0010] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0011] The preferred embodiments of this application will now be described in detail with reference to the accompanying drawings, so that the advantages and features of this application can be more easily understood by those skilled in the art, thereby providing a clearer and more definite definition of the scope of protection of this application.

[0012] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0013] In the PECVD thin film deposition process for semiconductor wafers, the spacing between the heater and the showerhead is a key process parameter affecting plasma distribution uniformity, film deposition rate, and film quality, directly determining the wafer deposition effect and yield. The moving speed of the heater directly affects the safe transport of the wafer and process stability, making it one of the core control parameters for the normal operation of the PECVD equipment. Currently, the existing technical solution in the industry is to adjust the spacing by moving the heater at a constant speed. This solution is widely used in various PECVD equipment and is the default spacing control method for mainstream PECVD equipment.

[0014] The existing technical solution has the following framework: a heating plate that can move up and down axially is installed at the bottom of the reaction chamber of the PECVD equipment, and a spray head is fixedly installed at the top of the reaction chamber. The wafer to be deposited is placed on a pin, which is fixed at the bottom of the reaction chamber and cannot be moved. The heating plate is moved so that the pin passes through a pre-set hole in the heating plate to support the wafer during the wafer loading and unloading steps. When the heating plate is in its initial position, its upper surface is lower than the upper surface of the pin. Before the process starts, the heating plate rises at a fixed speed until it reaches the preset target distance from the spray head, and the wafer adheres to the surface of the heating plate. Then, maintaining this distance, reactive gas is introduced and plasma is excited to complete the thin film deposition on the wafer surface. After the deposition process is completed, the heating plate descends at the same fixed speed to return to its initial position so that the wafer can be removed. The core design logic of this solution is to simplify the control process, achieve distance adjustment through a fixed speed, and reduce the complexity of equipment control.

[0015] However, existing technologies have significant drawbacks and cannot meet the demands of high-precision, high-yield semiconductor mass production. The root cause lies in the fact that the uniform-speed movement mode cannot match the core requirements of different stages of the PECVD process. During the initial rising phase of the heating pad, the wafer rests on its surface solely due to gravity. If the speed is too high, relative sliding can easily occur between the wafer and the heating pad, causing the wafer to wobble or shift, thus affecting the uniformity of subsequent thin film deposition and even rendering the wafer unusable. Conversely, using a low-speed, uniform movement to avoid wobble significantly prolongs the heating pad's arrival time, reducing process efficiency and increasing production time and costs. Simultaneously, during PECVD deposition, the wafer surface generates static electricity due to plasma bombardment. After deposition, if the heating pad continues to descend rapidly at a uniform speed, the unreleased static electricity will create electrostatic attraction between the wafer and the heating pad, leading to uneven stress on the wafer and increasing the risk of wafer breakage.

[0016] The inventive concept of this application is to provide a method for dynamically adjusting the moving speed of the heating plate during the PECVD deposition process. The core of this method is to dynamically adjust the moving speed of the heating plate according to its position during the rising and falling phases, thereby achieving a dual improvement in wafer safety and process efficiency, better adapting to the high-precision, high-yield semiconductor wafer PECVD deposition production requirements. By changing the spacing of the heating plate's uniform movement, the spacing is kept fixed during the deposition stage, with different moving speeds only used during the rising and falling phases. The rising phase employs a slow-start, fast-finish adjustment strategy to solve the wafer grazing or inefficiency problems caused by inappropriate speeds in existing technologies; the falling phase employs a fast-start, slow-finish adjustment strategy to solve the wafer breakage problem caused by incomplete static electricity discharge after deposition.

[0017] The technical solutions of this application and how they solve the aforementioned technical problems will be described in detail below with specific embodiments. The specific embodiments described below can be combined with each other to form new embodiments. The same or similar ideas or processes described in one embodiment may not be repeated in other embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0018] Figure 1 This paper illustrates a specific embodiment of a method for dynamically adjusting the moving speed of a heating plate in a PECVD process according to this application.

[0019] exist Figure 1 In the specific embodiment shown, the method for dynamically adjusting the moving speed of the heating plate in the PECVD process includes: step S101, monitoring the real-time position of the heating plate in the reaction chamber, and determining the moving direction of the heating plate based on the real-time position of the heating plate and the target position; step S102, dynamically configuring the preset moving speed of the heating plate corresponding to its current real-time position based on the real-time position; step S103, controlling the heating plate to move to the target position along the moving direction at the preset moving speed.

[0020] exist Figure 1 In the specific embodiment shown, this method changes the way the heating plate moves at a constant speed to adjust the spacing. A segmented speed dynamic adjustment strategy is adopted during the rising and falling phases of the heating plate to achieve a dual improvement in wafer safety and process efficiency, better meeting the needs of each stage of the PECVD process. At the same time, this application does not require large-scale equipment modification, effectively improving the uniformity of thin film deposition and wafer yield, reducing the wafer breakage rate of the PECVD deposition process by more than 30%, and better adapting to the high-precision, high-yield semiconductor wafer PECVD deposition production requirements.

[0021] exist Figure 1In the specific embodiment shown, step S101 involves monitoring the real-time position of the heating plate within the reaction chamber and determining the direction of movement of the heating plate based on its real-time position and the target position. In the PECVD equipment, the heating plate is located at the bottom of the reaction chamber and can move vertically along the axial direction. It is used to support the wafer and preheat the wafer using its internal preheating module to meet the temperature requirements of the thin film deposition process. Monitoring the real-time position of the heating plate within the reaction chamber includes using a heating plate position sensor to monitor its position in real time. Before performing thin film deposition on the wafer placed on the ejector pin of the heating plate within the reaction chamber, the heating plate is raised from its initial position to the target position so that the distance between the heating plate and the spray head fixedly located at the top of the reaction chamber meets the preset target distance required by the thin film deposition process. The ejector pin is fixedly located at the bottom of the reaction chamber and cannot move. The ejector pin passes through a preset through-hole on the heating plate to support the wafer. When the heating plate is in its initial position, its upper surface is lower than the upper surface of the ejector pin. After thin film deposition on the wafer, the heating plate is lowered back to its initial position.

[0022] exist Figure 1 In the specific embodiment shown, step S102 involves dynamically configuring the preset moving speed of the heating plate at its current real-time position based on the real-time location. During the moving phase of the heating plate, setting different moving speeds according to different positions of the heating plate helps avoid wafer movement due to improper speed during the initial rising phase of the heating plate, and helps prevent wafer damage due to incomplete static electricity discharge during the descending phase after deposition. This balances wafer safety and process efficiency, better matching the needs of each stage of the PECVD process.

[0023] In a preferred embodiment of this application, the preset moving speed of the heating plate at its current real-time position is dynamically configured based on the real-time position. This includes: obtaining the real-time distance between the heating plate and the spray head fixedly disposed at the top of the reaction chamber based on the real-time position; and dynamically configuring the preset moving speed of the heating plate at the current real-time distance based on the preset correspondence between the distance between the heating plate and the spray head and the moving speed of the heating plate, as well as the real-time distance. In the PECVD thin film deposition process, the distance between the heating plate and the spray head is a key process parameter affecting the uniformity of plasma distribution, the thin film deposition rate, and the thin film quality, directly determining the wafer deposition effect and yield. Dynamically adjusting the moving speed of the heating plate based on the real-time distance between the heating plate and the spray head allows for better control of the heating plate's movement, preventing wafer scratching or offset, and avoiding affecting the uniformity of subsequent thin film deposition.

[0024] In this preferred embodiment, the preset correspondence between the distance between the heating plate and the spray head and the moving speed of the heating plate includes a predetermined mapping relationship between the distance between the heating plate and the spray head and the moving speed. For example, a distance value corresponds to a moving speed, with a moving speed of V1 corresponding to a distance of D1 and a moving speed of V2 corresponding to a distance of D2, or all distance values ​​within a distance range correspond to the same moving speed. There is also a functional relationship between the distance between the heating plate and the spray head and the moving speed. During the movement of the heating plate, the moving speed is calculated in real time based on the real-time distance.

[0025] In a preferred embodiment of this application, the preset correspondence between the distance between the heating plate and the spray head and the moving speed of the heating plate includes: the moving speed of the heating plate decreases as the distance increases. The maximum value of the distance between the heating plate and the spray head is the distance value between the initial position of the heating plate and the spray head. When the real-time distance value is larger, i.e., closer to the maximum value, interference from the ejector pin exists. During the rising phase of the heating plate, the heating plate moves upward slowly from the initial position to contact the back side of the wafer placed on the ejector pin, thereby supporting the wafer to move upward. During the descending phase of the heating plate, the heating plate supports the wafer to move downward. When it descends to be flush with the ejector pin, the back side of the wafer contacts the upper surface of the ejector pin, thereby separating from the heating plate. In this case, reducing the moving speed of the heating plate helps to avoid wafer scratching and displacement, ensuring the positioning accuracy of the wafer.

[0026] In a preferred embodiment of this application, the preset correspondence between the distance between the heating plate and the spray head and the moving speed of the heating plate includes: when the moving direction of the heating plate is upward, if the distance is greater than the preset speed switching distance value, the moving speed of the heating plate is set to a first upward speed; and if the distance is less than the preset speed switching distance value, the moving speed of the heating plate is set to a second upward speed, wherein the second upward speed is greater than the first upward speed. When the moving direction of the heating plate is downward, if the distance is less than the preset speed switching distance value, the moving speed of the heating plate is set to a third downward speed; and if the distance is greater than the preset speed switching distance value, the moving speed of the heating plate is set to a fourth downward speed, wherein the third downward speed is greater than the fourth downward speed. By adopting a slow-start, fast-finish adjustment strategy during the rising phase of the heating plate, the problem of wafer scribbling or low efficiency caused by improper speed is effectively solved; by adopting a fast-start, slow-finish adjustment strategy during the falling phase of the heating plate, the problem of wafer breakage caused by incomplete discharge of static electricity after deposition is effectively solved.

[0027] In a preferred embodiment of this application, the preset speed switching interval value is equal to the distance between the spray head and the upper surface of the ejector pin fixed at the bottom of the reaction chamber. By switching the speed when the heating plate moves to the upper surface of the ejector pin, relative sliding between the wafer and the heating plate can be effectively avoided, preventing wafer scraping and displacement, ensuring the initial positioning accuracy of the wafer, and laying the foundation for subsequent thin film deposition or wafer unloading.

[0028] In a preferred embodiment of this application, when the heating plate moves upward, and the spacing equals a preset speed switching spacing value, the moving speed of the heating plate is linearly switched from a first upward speed to a second upward speed; when the heating plate moves downward, and the spacing equals a preset speed switching spacing value, the moving speed of the heating plate is linearly switched from a third downward speed to a fourth downward speed. By linearly switching the moving speed of the heating plate, vibration of the heating plate caused by sudden speed changes can be effectively avoided, thereby affecting the stability of the wafer.

[0029] In a preferred embodiment of this application, the time for linearly switching the heating plate's moving speed from a first ascending speed to a second ascending speed, and the time for linearly switching the heating plate's moving speed from a third descending speed to a fourth descending speed, are both less than or equal to 1 second. By shortening the speed switching time to less than one second, the total time required for the heating plate to move to the target position can be reduced, thereby improving process efficiency.

[0030] In a preferred embodiment of this application, the first ascent speed and the fourth descent speed are both in the range of 0.05 to 0.1 mm / s, and the second ascent speed and the third descent speed are both in the range of 0.1 to 0.5 mm / s. The first ascent speed and the fourth descent speed, as well as the second ascent speed and the third descent speed, only have the same range; in practical applications, the speeds may be the same or different.

[0031] exist Figure 1 In the specific embodiment shown, step S103 involves controlling the heating plate to move along the moving direction at a preset moving speed to the target position. By moving the heating plate to the target position at a dynamically adjusted moving speed during the rising and falling phases, both wafer safety and process efficiency are improved, laying a good foundation for subsequent thin film deposition and wafer unloading.

[0032] In a preferred embodiment of this application, controlling the heating plate to move along the moving direction at a preset moving speed to the target position includes: controlling a drive motor to drive the heating plate along the moving direction at a preset moving speed to the target position. By using a drive motor to drive the heating plate, it is beneficial to better and more accurately control the moving speed of the heating plate, thereby realizing dynamic adjustment of the moving speed according to the real-time position of the heating plate, thereby improving wafer safety and process efficiency.

[0033] In one specific embodiment of this application, a method for dynamically adjusting the moving speed of a heating plate in a PECVD process includes: before performing thin film deposition on a wafer placed on a pusher pin of the heating plate in a reaction chamber, raising the heating plate includes controlling the heating plate to move upward at a first rising speed until the upper surface of the heating plate is flush with the upper surface of the pusher pin and makes full contact with the back side of the wafer to be deposited; switching the rising speed of the heating plate and controlling the heating plate to move upward at a second rising speed until the distance between the heating plate and the top spray head in the reaction chamber is a preset target distance, wherein the second rising speed is greater than the first rising speed; after performing thin film deposition on the wafer, lowering the heating plate includes controlling the heating plate to move downward at a third falling speed until the upper surface of the heating plate is flush with the upper surface of the pusher pin and the back side of the deposited wafer contacts the upper surface of the pusher pin; switching the falling speed of the heating plate and controlling the heating plate to move downward at a fourth falling speed until the heating plate falls to a predetermined initial position, wherein the fourth falling speed is less than the third falling speed.

[0034] In this specific embodiment, the method employs a segmented speed dynamic adjustment strategy during the rising and falling phases of the heating plate, achieving a dual improvement in wafer safety and process efficiency, and better meeting the requirements of each stage of the PECVD process. When the heating plate moves upward at a slower first rising speed, the wafer relies solely on gravity to adhere to the positioning groove on the heating plate. This low-speed movement effectively avoids relative sliding between the wafer and the heating plate, preventing wafer slippage and offset, ensuring the initial positioning accuracy of the wafer, and laying the foundation for subsequent thin film deposition. When the heating plate moves upward at a faster second rising speed, the distance between the heating plate and the spray head is quickly reduced to the target distance, shortening the total time for the heating plate to rise and improving process efficiency.

[0035] In this specific embodiment, when the heating plate moves downward at a relatively fast third descent speed, the distance between the heating plate and the spray head is quickly increased. The rapid descent helps to shorten the contact time between the residual plasma and the wafer, reduce damage to the film surface, and accelerate the release of static electricity, laying the foundation for the subsequent slow descent. When the heating plate moves downward at a relatively slow fourth descent speed, the static electricity has not been completely released, and there is electrostatic adsorption between the wafer and the heating plate. If the wafer is quickly removed and the heating plate is quickly lowered, the wafer will only contact the upper surface of the ejector pin, which poses a risk of wafer breakage or slippage. The slow descent can avoid such risks.

[0036] Figure 2 The process flow of a specific embodiment of a method for dynamically adjusting the moving speed of a heating plate in a PECVD process according to this application is shown.

[0037] exist Figure 2In the specific embodiment shown, the thin film deposition process includes: wafer loading step S201, vacuuming and preheating step S202, parameter setting step S203, slow heating plate rising step S204, rapid heating plate rising step S205, thin film deposition step S206, rapid heating plate falling step S207, slow heating plate falling step S208, and vacuum breaking and wafer unloading step S209.

[0038] exist Figure 2 In the specific embodiment shown, the wafer loading step S201 includes placing the wafer to be deposited stably on the pin, ensuring that the wafer is in contact with the pin without offset or tilt, and ensuring that the positioning accuracy of the wafer is less than or equal to 0.5mm. This step can further prevent the wafer from slipping slightly during the movement of the heating plate and improve the positioning stability of the wafer.

[0039] exist Figure 2 In the specific embodiment shown, the vacuuming and preheating step S202 includes: closing the sealing door of the reaction chamber of the PECVD equipment, starting the vacuum pumping module to pump the pressure inside the chamber to below 5 millitorr (mTorr) to ensure that there are no air impurities in the reaction chamber and avoid affecting the film deposition quality; starting the preheating module inside the heating plate to preheat the temperature of the heating plate to 200 to 400°C for 1 to 3 minutes to avoid sudden temperature changes that could cause thermal stress on the wafer and thus damage the wafer; during the preheating process, the temperature sensor monitors the temperature of the heating plate in real time, and the temperature fluctuation is controlled within ±2°C to ensure uniform preheating.

[0040] exist Figure 2 In the specific embodiment shown, the parameter setting step S203 includes setting various process parameters through the controller. All parameters are quantifiable values, specifically as follows: the target distance between the heating plate and the spray head is 10 to 50 mm, and the initial distance L0 is 70 to 80 mm; the first rising speed V1 of the heating plate is 0.05 to 0.1 mm / s, the second rising speed V2 is 0.1 to 0.5 mm / s, and V1 < V2 is satisfied; the first falling speed V3 of the heating plate is 0.1 to 0.5 mm / s, the second falling speed V4 is 0.05 to 0.1 mm / s, and V3 > V4 is satisfied.

[0041] exist Figure 2In the specific embodiment shown, the slow-rising step S204 of the heating plate includes initiating the heating plate rising program through the controller, controlling the drive motor to drive the heating plate upward at a first rising speed V1. During this stage, the distance between the heating plate and the spray head gradually decreases from the initial distance L0. The advantage of this slow rising is that, because the wafer only relies on gravity to adhere to the positioning groove on the heating plate, the low-speed movement can effectively avoid relative sliding between the wafer and the heating plate, preventing wafer scratching and displacement, ensuring the initial positioning accuracy of the wafer, and laying the foundation for subsequent thin film deposition.

[0042] exist Figure 2 In the specific embodiment shown, the rapid ascent step S205 of the heating plate includes speed switching. When the surface of the heating plate is in full contact with the back of the wafer, and the real-time distance between the heating plate and the spray head is the same as the distance between the upper surface of the ejector pin and the spray head, the controller immediately sends a speed switching signal to switch the moving speed of the heating plate from V1=0.1mm / s to V2=0.5mm / s, and it continues to move upward. The speed switching process is smooth, with a switching time ≤1s, to avoid sudden speed changes that could cause vibration of the heating plate and thus affect wafer stability. The heating plate rises rapidly, and when the distance between the heating plate and the spray head meets the target value, it immediately sends a signal to the controller. After receiving the signal, the controller stops the drive motor, and the heating plate stops rising, maintaining the target distance unchanged. Simultaneously, the gas delivery module and the plasma excitation module are started, preparing for the deposition stage.

[0043] exist Figure 2 In the specific embodiment shown, the thin film deposition step S206 includes gas introduction. The gas delivery module is activated to introduce reactant gas and carrier gas into the chamber. Taking silicon nitride (SiN) thin film deposition as an example, the introduced gases include: silane (SiH4) at a flow rate of 800 to 1500 sccm; ammonia (NH3) at a flow rate of 700 to 1300 sccm; and nitrogen (N2) at a flow rate of 15000 to 20000 sccm. For silicon dioxide (SiO2) thin film deposition, the introduced gases include: tetraethyl orthosilicate (TEOS) at a flow rate of 1 to 2 g / min; oxygen (O2) at a flow rate of 5000 to 8000 sccm; and argon (Ar) as the carrier gas at a flow rate of 6000 to 9000 sccm. Gas flow rate fluctuations are controlled within ±0.1 sccm to ensure uniform gas mixing.

[0044] exist Figure 2In the specific embodiment shown, the thin film deposition step S206 further includes plasma excitation, starting the plasma excitation module, setting the RF power supply power to 300 to 1000W, and the frequency to 13.56MHz. The deposition time is set according to the required thin film thickness. During the deposition process, the heating plate temperature is maintained within ±2℃ of the target temperature, and the chamber pressure is maintained within ±0.1 Torr of the target value to ensure the stability of the deposition process.

[0045] exist Figure 2 In the specific embodiment shown, the rapid descent step S207 of the heating plate includes: after the deposition process is completed, shutting down the plasma excitation module and the gas delivery module, stopping plasma excitation and gas supply, and then the heating plate descends at a descent speed V3 = 0.5 mm / s to quickly increase the distance between the heating plate and the spray head. The advantage of this rapid descent is that it shortens the contact time between the residual plasma and the wafer, reduces surface damage to the thin film, and accelerates electrostatic discharge, laying the foundation for the subsequent slow descent.

[0046] exist Figure 2 In the specific embodiment shown, the slow descent step S208 of the heating plate includes speed switching. When the real-time distance between the heating plate and the spray head is the same as the distance between the upper surface of the ejector pin and the spray head, i.e., when the ejector pin contacts the back of the wafer, the drive motor is controlled to switch the moving speed of the heating plate from V3=0.5mm / s to V4=0.1mm / s, continuing to move downwards slowly. When the static electricity is not completely discharged, there is electrostatic attraction between the wafer and the heating plate. If the wafer is quickly removed, there is a risk of wafer breakage or slippage. This operation avoids such risks. When the heating plate descends to the initial position, the controller controls the drive motor to stop running, and the heating plate stops descending.

[0047] exist Figure 2 In the specific embodiment shown, the vacuum breaking and wafer unloading step S209 includes: when the heating plate reaches the initial position, the controller controls the drive motor to stop running and the heating plate stops descending; then the depressurization program of the vacuum pumping module is started to slowly restore the pressure in the chamber to atmospheric pressure; after the depressurization is completed, the chamber sealing door is opened and the wafer with the completed deposition is taken out by the robotic arm to complete the entire PECVD deposition.

[0048] exist Figure 2In the specific embodiment shown, this thin film deposition process maintains a fixed spacing during the deposition stage, employing different moving speeds only during the rising and falling phases of the heating plate. The rising phase utilizes a slow-start, fast-finish speed adjustment strategy to address wafer scrambling or inefficiency issues caused by inappropriate speeds in existing technologies. The falling phase employs a fast-start, slow-finish speed adjustment strategy to address wafer breakage caused by incomplete static electricity discharge after deposition. This thin film deposition process requires no large-scale equipment modifications, balances wafer safety and process efficiency, improves thin film deposition uniformity and wafer yield, and reduces the breakage rate of PECVD-deposited wafers by more than 30%, making it suitable for high-precision semiconductor manufacturing requirements.

[0049] Figure 3 This paper illustrates a specific embodiment of a device for dynamically adjusting the moving speed of a heating plate in a PECVD process according to this application.

[0050] exist Figure 3 In the specific embodiment shown, a device for dynamically adjusting the moving speed of a heating plate in a PECVD process includes: a module 301 for monitoring the real-time position of the heating plate in the reaction chamber and determining the moving direction of the heating plate based on the real-time position and the target position; a module 302 for dynamically configuring a preset moving speed corresponding to the current real-time position of the heating plate based on the real-time position; and a module 303 for controlling the heating plate to move to the target position along the moving direction at the preset moving speed.

[0051] The device for dynamically adjusting the moving speed of the heating plate in the PECVD process provided in this application can be used to execute the device and method for dynamically adjusting the moving speed of the heating plate in the PECVD process described in any of the above embodiments. The implementation principle and technical effect are similar, and will not be repeated here.

[0052] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0053] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0054] The above description is merely an embodiment of this application and does not limit the scope of protection of this application. Any equivalent structural transformations made based on the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of protection of this application.

Claims

1. A method of dynamically adjusting the moving speed of a heater plate in a PECVD process, characterized in that, include: Monitor the real-time position of the heating plate in the reaction chamber, and determine the direction of movement of the heating plate based on the real-time position of the heating plate and the target position; Based on the real-time position, the preset moving speed of the heating plate corresponding to its current real-time position is dynamically configured; The heating plate is controlled to move along the moving direction and at the preset moving speed to the target position.

2. The method of dynamically adjusting the moving speed of the heater plate in a PECVD process according to claim 1, wherein, The step of dynamically configuring the preset moving speed of the heating plate at its current real-time position based on the real-time position includes: Based on the real-time position, the real-time distance between the heating plate and the spray head fixedly installed at the top of the reaction chamber is obtained; Based on the preset correspondence between the distance between the heating plate and the spray head and the moving speed of the heating plate, as well as the real-time distance, the preset moving speed of the heating plate at the current real-time distance is dynamically configured.

3. The method of dynamically adjusting the moving speed of the heater plate in a PECVD process according to claim 2, wherein, The preset correspondence includes: The moving speed of the heating plate decreases as the distance increases.

4. The method of dynamically adjusting the moving speed of the heater plate in a PECVD process according to claim 2, wherein, The preset correspondence includes: When the heating plate moves upward, if the distance is greater than the preset speed switching distance value, the moving speed of the heating plate is set to a first upward speed, and if the distance is less than the preset speed switching distance value, the moving speed of the heating plate is set to a second upward speed, wherein the second upward speed is greater than the first upward speed. When the heating plate moves downwards, if the distance is less than the preset speed switching distance value, the moving speed of the heating plate is set to a third descending speed, and if the distance is greater than the preset speed switching distance value, the moving speed of the heating plate is set to a fourth descending speed, wherein the third descending speed is greater than the fourth descending speed.

5. The method of dynamically adjusting the moving speed of the heater plate in a PECVD process according to claim 4, wherein, The preset speed switching interval value is equal to the distance between the spray head and the upper surface of the pin fixed at the bottom of the reaction chamber.

6. The method of dynamically adjusting the moving speed of the heater plate in a PECVD process according to claim 4, wherein, Also includes: When the heating plate moves upward, and the distance is equal to the preset speed switching distance value, the moving speed of the heating plate is linearly switched from the first rising speed to the second rising speed. When the heating plate moves downwards, and the distance is equal to the preset speed switching distance value, the moving speed of the heating plate is linearly switched from the third descending speed to the fourth descending speed.

7. The method of dynamically adjusting the moving speed of the heater plate in a PECVD process according to claim 6, wherein, The time for linearly switching the moving speed of the heating plate from the first rising speed to the second rising speed, and the time for linearly switching the moving speed of the heating plate from the third falling speed to the fourth falling speed, are both less than or equal to 1 second.

8. The method of dynamically adjusting the moving speed of the heater plate in a PECVD process according to claim 4, wherein, The first ascent speed and the fourth descent speed are both in the range of 0.05 to 0.1 mm / s, and the second ascent speed and the third descent speed are both in the range of 0.1 to 0.5 mm / s.

9. The method of dynamically adjusting the moving speed of the heater plate in a PECVD process according to claim 1, wherein, Controlling the heating plate to move along the moving direction and at the preset moving speed to the target position includes: The control drive motor drives the heating plate to move along the moving direction and at the preset moving speed to the target position.

10. A device for dynamically adjusting the moving speed of a heating plate in a PECVD process, characterized in that, include: A module for monitoring the real-time position of the heating plate in the reaction chamber and determining the direction of movement of the heating plate based on the real-time position of the heating plate and the target position. A module for dynamically configuring the preset moving speed of the heating plate at its current real-time position based on the real-time position; A module for controlling the heating plate to move along the moving direction and at the preset moving speed to the target position.

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