Faraday shield device and control method thereof, semiconductor process equipment

Abstract

The application discloses a Faraday shielding device and a control method and a semiconductor process equipment thereof. The Faraday shielding device comprises a Faraday shielding structure body for shielding control of plasma; an OES signal acquisition module for acquiring spectral characteristic data in a plasma discharge process; a rotating drive module connected with the Faraday shielding structure body for driving the Faraday shielding structure body to rotate to adjust a shielding state of the Faraday shielding structure body; and a control module electrically connected with the OES signal acquisition module and the rotating drive module for judging whether the plasma has state jump according to the spectral characteristic data, generating a shielding state driving instruction when it is judged that the plasma has state jump, and sending the shielding state driving instruction to the rotating drive module to drive the rotating drive module to adjust the shielding state of the Faraday shielding structure body. The application can automatically switch the shielding state according to the plasma state, and enhance the shielding effect of the Faraday shielding device.

Description

Technical Field

[0001] This invention relates to the field of semiconductor equipment technology, and in particular to a Faraday shielding device and its control method, as well as semiconductor process equipment. Background Technology

[0002] Inductively coupled plasma (ICP) sources have been widely used in semiconductor thin film deposition, etching, and wafer surface treatment processes. ICP relies on RF coils to excite angular induced electric fields, giving it the outstanding advantage of stably maintaining high-density plasma. However, the plasma ignition stage and the high-density steady-state maintenance stage have different requirements for the electromagnetic field distribution within the cavity: the ignition process requires a high-intensity electric field to accelerate free electrons, break down the process gas, and quickly establish plasma; after the plasma jumps to H mode and forms a high-density discharge state, it is necessary to significantly weaken the excess radial electric field to alleviate charge accumulation in the quartz tube, shielding components, and cavity edges, and reduce high-energy particle bombardment and abnormal arcing failures.

[0003] Existing equipment generally uses a fixed Faraday shielding structure, which cannot adapt to the different electromagnetic field requirements of the two plasma operating conditions: when the shielding suppression effect is too strong, the radial electric field inside the cavity is insufficient, which may lead to delayed ignition or even failure to ignite; when the shielding suppression effect is too weak, the radial electric field is too high during the high-density discharge stage, which can easily cause abnormal discharge, sparking and other faults inside the cavity. At the same time, traditional fixed shielding does not have the ability to adapt to operating conditions and cannot automatically adjust the shielding strength according to the real-time working status of the plasma, making it difficult to meet the dual process requirements of rapid ignition and stable operation of high-density plasma. Summary of the Invention

[0004] This invention provides a Faraday shielding device and its control method, as well as semiconductor process equipment, which aims to achieve automatic switching of shielding state according to plasma state and enhance the shielding effect of the Faraday shielding device.

[0005] This invention provides a Faraday shielding device, comprising: The Faraday shielding structure body is used for shielding and controlling plasma in semiconductor manufacturing processes; The OES signal acquisition module is used to acquire spectral characteristic data during the plasma discharge process; A rotation drive module, connected to the Faraday shielding structure body, is used to drive the Faraday shielding structure body to rotate, so as to adjust the shielding state of the Faraday shielding structure body. The control module is electrically connected to the OES signal acquisition module and the rotation drive module, respectively. It is used to determine whether the plasma has undergone a state transition based on the spectral characteristic data, and when the plasma is determined to have undergone a state transition, it generates a shielding state drive command and sends it to the rotation drive module so that the rotation drive module drives the adjustment of the shielding state of the Faraday shielding structure body.

[0006] Furthermore, the Faraday shielding structure body includes an outer fixed shielding cylinder and an inner rotating shielding cylinder coaxially sleeved together; the outer fixed shielding cylinder is fixedly assembled to the inner wall of the plasma reaction chamber, and the inner rotating shielding cylinder is circumferentially rotatable and coaxially arranged inside the outer fixed shielding cylinder. Both the outer fixed shielding cylinder and the inner rotating shielding cylinder have shielding through slots extending axially on their cylinder walls. By rotating the inner rotating shielding cylinder circumferentially, the shielding through slots of the inner and outer layers are aligned and connected or staggered and blocked, so as to adjust the shielding strength of the Faraday shielding structure body.

[0007] Furthermore, the OES signal acquisition module includes a fiber-coupled photodetector, which is disposed on the outer wall of the plasma reaction chamber and faces the discharge region of the plasma.

[0008] Furthermore, the rotary drive mechanism includes a drive motor, a reduction gear transmission assembly, and a rotary transmission component; the output end of the drive motor is connected to the rotary transmission component via the reduction gear transmission assembly, and the rotary transmission component is rigidly connected to the end of the inner rotary shielding cylinder, for driving the inner rotary shielding cylinder to rotate circumferentially around the axis.

[0009] Furthermore, the drive motor is a stepper motor or a servo motor; the reduction transmission assembly includes a coupling, a reducer and a gear transmission pair connected in sequence; the control terminal of the drive motor is electrically connected to the control module and is used to receive the rotation angle control signal output by the main control unit.

[0010] This invention also provides a control method for a Faraday shielding device as described in any of the preceding claims, comprising: The spectral characteristic data of plasma at different stages are acquired using the OES signal acquisition module; Determine whether the plasma undergoes a state transition based on the spectral characteristic data; When a state transition of the plasma is detected, a shielding state driving command is generated; The shielding state driving command is sent to the rotation driving module so that the rotation driving module drives the adjustment of the shielding state of the Faraday shielding structure body.

[0011] Furthermore, determining whether the plasma undergoes a state transition based on the spectral characteristic data includes: Based on threshold data of different state stages, the spectral characteristic data of the plasma are monitored for state transitions; wherein, the state stages include the plasma ignition stage, the high-density maintenance stage, and the abnormal state. When the spectral characteristic data of the plasma is detected to meet the threshold data for the transition from the ignition stage to the high-density maintenance stage, it is determined that the plasma has undergone a state transition. When the spectral characteristic data of the plasma is detected to match the abnormal state threshold data, it is determined that the plasma is abnormal.

[0012] Furthermore, the step of generating a shielding state driving command when determining that the plasma has undergone a state transition includes: When it is determined that the plasma jumps from the ignition stage to the high-density maintenance stage, a first shielding state driving command is generated to drive the Faraday shielding structure body to switch from the ignition state to the maintenance state. When an abnormality is detected in the plasma, a second shielding state driving command is generated to drive the Faraday shielding structure body to return to the ignition state or enter the protection mode. The Faraday shielding structure is ignited when the inner rotating shielding cylinder and the outer fixed shielding cylinder have their shielding seams axially aligned. It is maintained when the inner rotating shielding cylinder rotates circumferentially relative to the outer fixed shielding cylinder by a set angle, with the inner and outer shielding seams interleaved. The protection mode of the Faraday shielding structure involves locking or resetting the inner rotating shielding cylinder to the ignition state via a rotating drive mechanism, simultaneously triggering the RF power-off logic to terminate the plasma discharge.

[0013] Furthermore, the step of generating a shielding state driving command when determining that the plasma has undergone a state transition also includes: The rotation drive module acquires the position data of the Faraday shielding structure body. The rotation drive data of the rotation drive module is determined based on the position data; The shielding state drive command is generated by combining the rotation drive data.

[0014] This invention also provides a semiconductor process apparatus, including the Faraday shielding device described above.

[0015] This invention provides a Faraday shielding device and its control method, as well as semiconductor process equipment. The invention uses an OES signal acquisition module to collect spectral characteristic data during the plasma discharge process in real time. The control module accurately identifies the current working state of the plasma based on this data. When a state change occurs in the plasma, a corresponding driving command is generated and sent to the rotation drive module. The rotation drive module adjusts the shielding strength of the Faraday shielding structure, adaptively matching the different electromagnetic field distribution requirements of the plasma ignition and high-density maintenance stages. This ensures a sufficiently strong electric field during the ignition stage for rapid ignition, while simultaneously reducing excess radial electric field during the high-density stable discharge stage, decreasing charge accumulation within the cavity, and reducing the occurrence of high-energy particle bombardment and abnormal arcing failures. This balances the dual process requirements of rapid ignition and stable high-density plasma operation, effectively improving the stability of the semiconductor process and product yield. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the main body structure of a Faraday shielding device provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the inner rotating shielding cylinder structure in a Faraday shielding device provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the shielding state of the Faraday shielding structure body in a Faraday shielding device provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of another shielding state of the Faraday shielding structure body in a Faraday shielding device provided in an embodiment of the present invention; Figure 5 This is a simulation diagram of a Faraday shielding device provided in an embodiment of the present invention; Figure 6 This is a flowchart illustrating a control method for a Faraday shielding device provided in an embodiment of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0020] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0021] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0022] Please see below. Figure 1 This invention provides a Faraday shielding device, comprising: The Faraday shielding structure body 10 is used for shielding and controlling plasma in semiconductor manufacturing processes. The OES signal acquisition module is used to acquire spectral characteristic data during the plasma discharge process; A rotation drive module is connected to the Faraday shielding structure body 10 and is used to drive the Faraday shielding structure body 10 to rotate in order to adjust the shielding state of the Faraday shielding structure body 10. The control module is electrically connected to the OES signal acquisition module and the rotation drive module, respectively. It is used to determine whether the plasma has undergone a state transition based on the spectral characteristic data. When the plasma is determined to have undergone a state transition, it generates a shielding state drive command and sends it to the rotation drive module so that the rotation drive module drives the adjustment of the shielding state of the Faraday shielding structure body 10.

[0023] In this embodiment, the Faraday shielding device specifically includes a Faraday shielding structure body 10, an OES (Optical Emission Spectroscopy) signal acquisition module, a rotation drive module, and a control module. The OES signal acquisition module collects spectral characteristic data during the plasma discharge process in real time, and the control module accurately identifies the current working state of the plasma based on this data. When a state change occurs in the plasma, the control module promptly generates a corresponding drive command and sends it to the rotation drive module. The rotation drive module adjusts the shielding strength of the Faraday shielding structure body 10, which can adaptively match the different requirements of electromagnetic field distribution during the plasma ignition stage and the high-density maintenance stage. This ensures a sufficiently strong electric field during the ignition stage for rapid ignition and weakens the excess radial electric field during the high-density stable discharge stage, reducing charge accumulation in the cavity and minimizing the occurrence of high-energy particle bombardment and abnormal arcing failures. Thus, it meets the dual process requirements of rapid ignition and stable operation of high-density plasma, effectively improving the stability of the semiconductor process and product yield.

[0024] In practical applications, the control logic of this embodiment is as follows: Before the device starts ignition, the Faraday shielding structure body 10 maintains the ignition position; when the OES detects that the spectral data meets the threshold for the transition from E mode to H high-density maintenance mode, the control module automatically issues a drive command to drive the shielding structure to switch to the maintenance position. This significantly weakens the radial electric field while ensuring stable output of high-density plasma with almost no attenuation of the angular induced electric field, alleviating charge accumulation in the chamber and reducing the risk of arcing; if the spectral intensity is detected to be lower than the threshold, or if it matches abnormal discharge characteristics, a command is issued to control the shielding to reset to the ignition state, or to link the RF power supply to enter the whole machine protection mode. The entire hardware architecture is simple and compact, with rapid response in signal transmission and execution links, and can be seamlessly integrated into industrial HDP-type ICP thin film deposition and etching equipment, adapting to the mass production needs of high-precision semiconductor processes.

[0025] In a specific embodiment, combined with Figures 2-4 The Faraday shielding structure body 10 includes an outer fixed shielding cylinder 11 and an inner rotating shielding cylinder 12 coaxially sleeved together; the outer fixed shielding cylinder 11 is fixedly assembled to the inner wall of the plasma reaction chamber, and the inner rotating shielding cylinder 12 is rotatably and coaxially arranged inside the outer fixed shielding cylinder 11. Both the outer fixed shielding cylinder 11 and the inner rotating shielding cylinder 12 have shielding through slots extending axially on their cylinder walls. By rotating the inner rotating shielding cylinder 12 circumferentially, the shielding through slots of the inner and outer layers are aligned and connected or staggered and blocked, so as to adjust the shielding strength of the Faraday shielding structure body 10.

[0026] In this embodiment, the Faraday shielding structure body 10 specifically includes an outer fixed shielding cylinder 11 and an inner rotating shielding cylinder 12. Both the outer fixed shielding cylinder 11 and the inner rotating shielding cylinder 12 can be made of highly conductive metal material to ensure their shielding and blocking capabilities against radial induced electric fields. Figure 3 As shown, when the inner rotating shielding cylinder 12 rotates to the position where the inner and outer shielding seams are aligned and connected, the electromagnetic field can penetrate through the seams into the reaction chamber. The overall shielding strength is relatively weak, but the radial electric field within the chamber is sufficient to accelerate electron movement and break down the process gas, making it suitable for plasma ignition conditions. Figure 4 As shown, when the inner rotating shielding cylinder 12 rotates relative to the outer fixed shielding cylinder 11 to the position of staggered shielding, most of the radial electromagnetic field is blocked by the double-layer shielding structure, and the overall shielding strength is significantly improved. This can greatly reduce the excess radial electric field in the high-density H-mode discharge stage, alleviate the charge accumulation on the surface of the chamber, quartz cylinder and shielding components, reduce the probability of high-energy particle bombardment and abnormal arcing, reduce component wear, and extend the service life of the quartz cylinder and shielding cylinder.

[0027] In a specific embodiment, the OES signal acquisition module includes a fiber-coupled photodetector, which is disposed on the outer wall of the plasma reaction chamber and faces the discharge region of the plasma.

[0028] This embodiment uses a fiber-coupled photodetector to acquire spectral characteristic data of the entire plasma discharge process. Employing fiber optic transmission for signal acquisition avoids signal interference from the strong electromagnetic field within the reaction cavity, outputting stable and high-precision spectral data, providing a reliable basis for identifying the plasma's operational status. Furthermore, the fiber-coupled photodetector is only positioned against the outer wall of the reaction cavity, acquiring the emitted signal through an external optical window without penetrating the discharge cavity. This avoids interfering with the plasma distribution within the cavity and prevents the probe from being directly bombarded by high-energy plasma particles, effectively improving the operational stability and lifespan of the entire acquisition module.

[0029] In practical applications, the spectral characteristic data can be plasma luminescence intensity, characteristic spectral line intensity, or spectral line intensity ratio, etc. Specifically, it can be flexibly selected according to the plasma spectral characteristics of different process types and different gas components to adapt to the needs of different semiconductor process scenarios.

[0030] In a specific embodiment, the rotary drive mechanism includes a drive motor, a reduction transmission assembly, and a rotary transmission component; the output end of the drive motor is connected to the rotary transmission component via the reduction transmission assembly, and the rotary transmission component is rigidly connected to the end of the inner rotary shielding cylinder 12, for driving the inner rotary shielding cylinder 12 to rotate circumferentially around the axis.

[0031] Furthermore, the drive motor is a stepper motor or a servo motor; the reduction transmission assembly includes a coupling, a reducer and a gear transmission pair connected in sequence; the control terminal of the drive motor is electrically connected to the control module and is used to receive the rotation angle control signal output by the main control unit.

[0032] In this embodiment, a stepper motor or servo motor is selected as the power source. The motor can receive the rotation control signal issued by the control module to achieve precise angle output, thereby driving the inner rotating shielding cylinder 12 to be positioned at the target position and completing the precise adjustment of the shielding strength. The coupling connects the motor output shaft and the reducer input shaft, which can not only buffer the vibration and impact during the transmission process, but also compensate for the alignment deviation caused by the assembly of the two shafts, improving the running stability of the entire transmission link. The reducer and the gear transmission pair form a two-stage reduction structure, which can reduce the output speed of the motor and synchronously amplify the output torque, providing sufficient driving force for the heavy inner rotating shielding cylinder 12, while further reducing the angle control error, eliminating the problems of rotation overtravel and positioning offset, and ensuring that the shielding state switching accurately matches the requirements of various plasma working conditions. The rotating transmission component is rigidly connected to the end of the inner rotating shielding cylinder 12, with minimal transmission gap, and no lag or offset in power transmission, which can stably and reliably drive the inner shielding cylinder to complete the circumferential rotation adjustment.

[0033] In other embodiments, other rotary drive devices with high-precision angle positioning capabilities can also be used to drive the inner rotating shield cylinder 12 to complete circumferential adjustment. For example, a linear module combined with a rack and pinion transmission structure can be selected to convert linear reciprocating motion into cylinder rotational motion; alternatively, a pneumatic rotary actuator can be used as the power output unit, relying on air pressure to achieve shield cylinder angle switching. Any drive scheme that can accurately control the rotation angle of the inner rotating shield cylinder 12, meet the positioning accuracy required for switching between ignition and high-density maintenance states, and can stably output torque to drive the shield cylinder to rotate smoothly is applicable to the scheme of this embodiment.

[0034] In practical applications, the electromagnetic field distribution and field strength values ​​within the cavity under shielded ignition and high-density maintenance states were simulated and verified using HFSS electromagnetic simulation software. The simulation results are as follows: Figure 5 As shown, after the Faraday shield switches from the ignition position to the maintenance position, the angular induced electric field strength only decreases slightly from 72.5 V / m to 70.8 V / m, with an extremely low attenuation; while the radial induced electric field strength decreases significantly from 29.8 V / m to 9.37 V / m, demonstrating a prominent suppression effect.

[0035] The simulation data above fully demonstrates that this embodiment can directionally weaken the excess radial electric field in the cavity while maintaining high-density plasma with almost no loss of ICP RF coil inductive coupling efficiency and stable maintenance, thus simultaneously achieving the dual process objectives of stable operation of high-density plasma and control of abnormal arcing risk in the cavity.

[0036] like Figure 6 As shown, this embodiment of the invention also provides a control method applied to the Faraday shielding device as described above, specifically including steps S101 to S104.

[0037] Step S101: Acquire spectral characteristic data of plasma at different stages using the OES signal acquisition module; Step S102: Determine whether the plasma has undergone a state transition based on the spectral characteristic data; Step S103: When it is determined that the plasma has undergone a state transition, a shielding state driving command is generated; Step S104: Send the shielding state driving command to the rotation driving module so that the rotation driving module drives the adjustment of the shielding state of the Faraday shielding structure body 10.

[0038] In this embodiment, the spectral characteristic data of the plasma at different operating stages are first obtained through the OES signal acquisition module. Then, based on the acquired spectral characteristic data, it is determined whether the plasma has undergone a state transition. If it is determined that the plasma has undergone a state transition, a corresponding shielding state driving command is generated. Finally, the generated shielding state driving command is sent to the rotation driving module, so that the rotation driving module drives the Faraday shielding structure body 10 to complete the adjustment of the shielding state, thereby adapting to the state change of the plasma.

[0039] This embodiment achieves fully automated closed-loop control through real-time OES spectral monitoring, eliminating the need for manual intervention in the shielding structure switching. It features rapid response and accurate condition identification. It can simultaneously adapt to three operating conditions: plasma ignition (E mode), high-density (H mode), and abnormal discharge, while simultaneously meeting the two core process requirements of rapid ignition and stable high-density plasma operation. On one hand, this embodiment maintains a sufficient radial electric field during the ignition stage, ensuring rapid breakdown and ignition of the process gas, overcoming the difficulty of ignition in traditional fixed shielding systems. On the other hand, this embodiment actively weakens the redundant radial electric field during the high-density discharge stage, reducing charge accumulation, particle bombardment, and abnormal arcing faults within the cavity, thus improving wafer processing yield. Furthermore, this embodiment has simple logic and low hardware integration difficulty, directly adapting to existing HDP-ICP semiconductor thin film deposition and etching equipment, demonstrating strong versatility. It can also eliminate transmission assembly errors through closed-loop position calibration, ensuring positioning accuracy during shielding state switching, effectively extending the service life of core vulnerable components such as the quartz cylinder and Faraday shield cylinder, and reducing equipment maintenance costs.

[0040] In one embodiment, determining whether the plasma has undergone a state transition based on the spectral feature data includes: Based on threshold data of different state stages, the spectral characteristic data of the plasma are monitored for state transitions; wherein, the state stages include the plasma ignition stage, the high-density maintenance stage, and the abnormal state. When the spectral characteristic data of the plasma is detected to meet the threshold data for the transition from the ignition stage to the high-density maintenance stage, it is determined that the plasma has undergone a state transition. When the spectral characteristic data of the plasma is detected to match the abnormal state threshold data, it is determined that the plasma is abnormal.

[0041] This embodiment pre-configures dedicated spectral intensity threshold ranges for the ignition stage, high-density maintenance stage, and abnormal discharge state. During operation, the spectral feature data collected in real time by the OES module is continuously compared with each preset threshold to track changes in plasma conditions in real time. If the spectral data falls within the threshold range corresponding to the transition from the ignition stage to the high-density maintenance stage, the EH mode transition determination can be completed, thereby quickly issuing a shielding switching command and timely adjusting the shielding intensity to ensure that the shielding state matches the plasma discharge condition in real time, without any lag in condition adaptation. If the spectral data matches the abnormal state threshold, an abnormal discharge is determined to have occurred in the cavity, providing early warning and triggering the discharge protection logic to avoid the risks of process defects, chamber arcing, and damage to components such as the quartz tube and shielding cylinder caused by continuous abnormal discharge. The entire determination logic relies on spectral threshold comparison, resulting in fast identification response speed and high accuracy in distinguishing operating conditions, and can stably support the fully automatic adaptive control of the Faraday shielding device.

[0042] In one embodiment, generating a shielding state driving command when a state transition of the plasma is determined includes: When it is determined that the plasma jumps from the ignition stage to the high-density maintenance stage, a first shielding state driving command is generated to drive the Faraday shielding structure body 10 to switch from the ignition state to the maintenance state. When an abnormality is detected in the plasma, a second shielding state driving command is generated to drive the Faraday shielding structure body 10 to return to the ignition state or enter the protection mode. The Faraday shielding structure body 10 is in an ignition state where the shielding seams of the inner rotating shielding cylinder 12 and the outer fixed shielding cylinder 11 are axially aligned. The Faraday shielding structure body 10 is in a maintenance state where the inner rotating shielding cylinder 12 rotates circumferentially relative to the outer fixed shielding cylinder 11 by a set angle, and the inner and outer shielding seams are staggered. The Faraday shielding structure body 10 is in a protection mode where the rotation drive mechanism locks or drives the inner rotating shielding cylinder 12 back to the ignition state, while triggering the radio frequency power-off logic to terminate the plasma discharge.

[0043] This embodiment matches the corresponding Faraday shielding working state according to different plasma operating conditions. It achieves adaptive adjustment of the electromagnetic field environment through differentiated driving commands, ensuring that the electric field distribution at each process stage meets production requirements. For example, during the plasma ignition stage, the inner and outer shielding seams are axially aligned, resulting in a weak overall shielding suppression effect. Sufficient radial electric field accelerates free electrons and breaks down process gases, ensuring rapid plasma ignition. After entering the high-density maintenance state, the inner shielding cylinder rotates to the staggered seam blocking position, significantly improving shielding suppression capability. This greatly reduces redundant radial electric field, optimizes plasma uniformity within the cavity, alleviates charge accumulation on the cavity wall, quartz cylinder, and shielding components, effectively reduces high-energy particle bombardment and abnormal arcing failures, and extends the service life of core components in the cavity. When an abnormal plasma discharge is detected, the second shielding state driving command can promptly switch to protection mode. On one hand, it locks the driving mechanism or resets the shielding cylinder to the ignition position; on the other hand, it simultaneously cuts off the RF output to terminate the discharge, quickly preventing the abnormal operating conditions from worsening, avoiding wafer process scrap and irreversible equipment damage, and comprehensively improving the operational stability and safety of the semiconductor thin film fabrication process.

[0044] In one embodiment, generating a shielding state driving command when a state transition of the plasma is determined to occur further includes: The position data of the Faraday shielding structure body 10 is obtained through the rotation drive module; The rotation drive data of the rotation drive module is determined based on the position data; The shielding state drive command is generated by combining the rotation drive data.

[0045] This embodiment adds a closed-loop position calibration logic. The rotation drive module collects the current actual position data of the inner rotating shielding cylinder 12 in real time, performs difference calculation between the real-time position and the target standard position corresponding to the current working condition, and accurately solves the rotation drive parameters such as the rotation angle, speed and output torque required by the drive mechanism. Then, the set of parameters is integrated and packaged to form the final shielding state drive command. This method can eliminate the control error caused by the initial positioning deviation of the shielding cylinder and the transmission assembly gap, effectively avoid defects such as cylinder rotation not reaching the correct position and rotation overtravel misalignment, further improve the positioning accuracy of shielding state switching, and ensure that the Faraday shielding structure body 10 can accurately reach the ignition position or high-density maintenance position every time, so that the shielding strength is accurately matched with the plasma discharge condition.

[0046] For example, the system presets the ignition position to correspond to the 0° reference position of the inner shielding cylinder, and the high-density maintenance position to correspond to the 60° target position. If the drive module collects the actual position of the shielding cylinder at 5° in real time, the main control unit will calculate the 55° difference angle, synchronously match the appropriate output torque and rotation speed, and then write the set of drive parameters into the first shielding state drive command and send it to the motor. If this closed-loop calibration logic is not introduced, the motor will directly output a fixed 60° angle. After adding the initial offset of 5°, the actual angle of the cylinder will reach 65°, which will cause the shielding angle of the inner and outer shielding seams to exceed the standard, the radial electric field suppression intensity to exceed the process requirements, and the stable maintenance of high-density plasma to be destroyed. After introducing real-time position calibration, the motor only performs a precise 55° rotation, and the cylinder stops exactly at the 60° standard position. The degree of staggering of the shielding seams fully matches the process design requirements.

[0047] This invention also provides a semiconductor process apparatus, including the Faraday shielding device described above.

[0048] The semiconductor process equipment, employing the aforementioned Faraday shielding device, achieves dynamic adaptive control of the plasma electromagnetic field under all operating conditions, simultaneously addressing the dual process requirements of rapid ignition during the ignition phase and high-density H-mode steady-state discharge. While ensuring efficient excitation of the RF coil and maintaining high-density plasma, the equipment automatically adjusts the shielding strength based on plasma EH mode transitions, precisely reducing redundant radial induced electric fields within the cavity. This significantly alleviates the problem of continuous charge accumulation on the surfaces of components such as the quartz cylinder, shielding cylinder, and cavity edges, greatly reducing equipment wear and wafer process defects caused by abnormal arcing and continuous bombardment by high-energy particles within the cavity. The entire adaptive control mechanism requires no manual intervention and can automatically match real-time plasma conditions throughout the process. This improves the yield of semiconductor processing processes such as thin film deposition and etching, reduces the replacement frequency of core cavity components, extends equipment service life, and is highly suitable for the stringent process standards of high-precision HDP-ICP semiconductor thin film preparation.

[0049] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to in the method section. It should be noted that those skilled in the art can make various improvements and modifications to this application without departing from the principles of this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

[0050] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only 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 one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A Faraday shielding device, characterized in that, include: The Faraday shielding structure body is used for shielding and controlling plasma in semiconductor manufacturing processes; The OES signal acquisition module is used to acquire spectral characteristic data during the plasma discharge process; A rotation drive module, connected to the Faraday shielding structure body, is used to drive the Faraday shielding structure body to rotate, so as to adjust the shielding state of the Faraday shielding structure body. The control module is electrically connected to the OES signal acquisition module and the rotation drive module, respectively. It is used to determine whether the plasma has undergone a state transition based on the spectral characteristic data, and when the plasma is determined to have undergone a state transition, it generates a shielding state drive command and sends it to the rotation drive module so that the rotation drive module drives the adjustment of the shielding state of the Faraday shielding structure body.

2. The Faraday shielding device according to claim 1, characterized in that, The Faraday shielding structure body includes an outer fixed shielding cylinder and an inner rotating shielding cylinder coaxially sleeved together; the outer fixed shielding cylinder is fixedly assembled to the inner wall of the plasma reaction chamber, and the inner rotating shielding cylinder is rotatably and coaxially arranged inside the outer fixed shielding cylinder. Both the outer fixed shielding cylinder and the inner rotating shielding cylinder have shielding through slots extending axially on their cylinder walls. By rotating the inner rotating shielding cylinder circumferentially, the shielding through slots of the inner and outer layers are aligned and connected or staggered and blocked, so as to adjust the shielding strength of the Faraday shielding structure body.

3. The Faraday shielding device according to claim 1, characterized in that, The OES signal acquisition module includes a fiber-coupled photodetector, which is disposed on the outer wall of the plasma reaction chamber and faces the discharge region of the plasma.

4. The Faraday shielding device according to claim 2, characterized in that, The rotary drive mechanism includes a drive motor, a reduction gear transmission assembly, and a rotary transmission component; the output end of the drive motor is connected to the rotary transmission component via the reduction gear transmission assembly, and the rotary transmission component is rigidly connected to the end of the inner rotary shielding cylinder, for driving the inner rotary shielding cylinder to rotate circumferentially around the axis.

5. The Faraday shielding device according to claim 4, characterized in that, The drive motor is a stepper motor or a servo motor; the reduction transmission assembly includes a coupling, a reducer and a gear transmission pair connected in sequence; the control terminal of the drive motor is electrically connected to the control module and is used to receive the rotation angle control signal output by the main control unit.

6. A control method applied to the Faraday shielding device as described in any one of claims 1-5, characterized in that, include: The spectral characteristic data of plasma at different stages were acquired using the OES signal acquisition module; Determine whether the plasma undergoes a state transition based on the spectral characteristic data; When a state transition of the plasma is detected, a shielding state driving command is generated; The shielding state driving command is sent to the rotation driving module so that the rotation driving module drives the adjustment of the shielding state of the Faraday shielding structure body.

7. The control method according to claim 6, characterized in that, The step of determining whether the plasma has undergone a state transition based on the spectral feature data includes: Based on threshold data of different state stages, the spectral characteristic data of the plasma are monitored for state transitions; wherein, the state stages include the plasma ignition stage, the high-density maintenance stage, and the abnormal state. When the spectral characteristic data of the plasma is detected to meet the threshold data for the transition from the ignition stage to the high-density maintenance stage, it is determined that the plasma has undergone a state transition. When the spectral characteristic data of the plasma is detected to match the abnormal state threshold data, it is determined that the plasma has become abnormal.

8. The control method according to claim 7, characterized in that, The step of generating a shielding state driving command when determining that the plasma has undergone a state transition includes: When it is determined that the plasma jumps from the ignition stage to the high-density maintenance stage, a first shielding state driving command is generated to drive the Faraday shielding structure body to switch from the ignition state to the maintenance state. When an abnormality is detected in the plasma, a second shielding state driving command is generated to drive the Faraday shielding structure body to return to the ignition state or enter the protection mode. The Faraday shielding structure is ignited when the inner rotating shielding cylinder and the outer fixed shielding cylinder have their shielding seams axially aligned. It is maintained when the inner rotating shielding cylinder rotates circumferentially relative to the outer fixed shielding cylinder by a set angle, with the inner and outer shielding seams interleaved. The protection mode of the Faraday shielding structure involves locking or resetting the inner rotating shielding cylinder to the ignition state via a rotating drive mechanism, simultaneously triggering the RF power-off logic to terminate the plasma discharge.

9. The control method according to claim 6, characterized in that, The step of generating a shielding state driving command when determining that the plasma has undergone a state transition further includes: The rotation drive module acquires the position data of the Faraday shielding structure body. The rotation drive data of the rotation drive module is determined based on the position data; The shielding state drive command is generated by combining the rotation drive data.

10. A semiconductor process apparatus, characterized in that, Includes the Faraday shielding device as described in any one of claims 1-5.

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