Microwave plasma reaction apparatus and thin film deposition method, storage medium

Abstract

This invention discloses a microwave plasma reaction apparatus, a thin film deposition method, and a storage medium. The microwave plasma reaction apparatus includes: an inner cavity in which a wafer is placed for plasma deposition; an outer cavity surrounding the outer side of the inner cavity; and multiple lateral antennas extending laterally through the sidewalls of the outer cavity and circumferentially distributed outside the inner cavity to couple microwave energy into the inner cavity from multiple directions, forming a plasma region. The multiple lateral antennas are allowed to move laterally to support their movement to an optimal coupling depth. This invention can effectively compensate for the intensity differences of the circumferential electromagnetic field within the reaction cavity, achieving uniform matching of the electromagnetic field across the entire domain, thereby improving the uniformity of the plasma distribution within the cavity and contributing to the improvement of the uniformity and quality stability of the deposited thin film.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, specifically to a microwave plasma reaction apparatus, a thin film deposition method, and a computer-readable storage medium. Background Technology

[0002] Microwave plasma chemical vapor deposition (MPCVD) is an advanced process that uses microwave energy to excite plasma for material deposition. In the MPCVD reaction chamber, when the plasma and the deposition stage on which the wafer is placed are aligned, high-quality diamond films can be deposited.

[0003] Currently, in existing MPCVD reaction cavities, microwave antennas are typically inserted from the top and / or bottom of the cavity to inject their radiated energy axially (vertically) within the cavity. After microwaves are reflected and superimposed within the cavity, the electromagnetic field modes are confined to an axially dominant distribution (e.g., TM). 011 TE 012 (Single mode), the resonant region is concentrated between the antenna and the deposition stage, generally closer to the deposition stage. Furthermore, the upper and / or lower ends of the MPCVD reaction cavity are typically equipped with only one longitudinal antenna, coaxial with the cavity. Because the energy injection direction is fixed axially, the distribution of electromagnetic field modes within the cavity exhibits a pattern of strong intensity in the center and weak intensity at the edges. In actual deposition processes, the wafer region near the longitudinal antenna (e.g., directly above or below it) deposits a thicker film, while the wafer region farther from the antenna deposits a thinner film. That is, even with multiple antennas arranged longitudinally, the electromagnetic field within the cavity is still mainly distributed along the axial direction, with significant differences in circumferential electromagnetic field intensity, making it impossible to flexibly adjust the plasma in the circumferential direction. Therefore, the uniformity of the plasma and its temperature distribution is difficult to control. The uniformity of film thickness deposited using existing MPCVD reaction cavities is poor.

[0004] To address the aforementioned problems in the existing technology, there is an urgent need in the field for an improved microwave plasma reaction technology that can effectively compensate for the intensity differences of the circumferential electromagnetic field within the reaction cavity, achieve uniform matching of the electromagnetic field across the entire domain, thereby improving the uniformity of the plasma distribution within the cavity and contributing to enhancing the uniformity and quality stability of the deposited thin film. Summary of the Invention

[0005] The following provides a brief overview of one or more aspects to offer a basic understanding of them. This overview is not an exhaustive summary of all conceived aspects, nor is it intended to identify key or decisive elements of all aspects, nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed descriptions that follow.

[0006] To overcome the aforementioned deficiencies in the prior art, the present invention provides a microwave plasma reaction apparatus, a thin film deposition method, and a computer-readable storage medium, which can effectively compensate for the intensity differences of the circumferential electromagnetic field within the reaction cavity, achieve uniform matching of the electromagnetic field across the entire domain, thereby improving the uniformity of the plasma distribution within the cavity and contributing to enhancing the uniformity and quality stability of the deposited thin film.

[0007] Specifically, the microwave plasma reaction apparatus according to the first aspect of the present invention includes: an inner cavity in which a wafer is placed for plasma deposition reaction; an outer cavity surrounding the outside of the inner cavity; and a plurality of lateral antennas extending laterally through the sidewalls of the outer cavity and circumferentially distributed outside the inner cavity to couple microwave energy into the inner cavity from multiple directions to form a plasma region, wherein the plurality of lateral antennas are allowed to move laterally to support the lateral movement of the plurality of lateral antennas to an optimal coupling depth position.

[0008] Furthermore, in some embodiments of the present invention, the microwave plasma reaction device includes: a power unit installed at the end of each of the lateral antennas, for driving the lateral displacement of the plurality of lateral antennas and adjusting the lateral parameters of the plasma region.

[0009] Furthermore, in some embodiments of the present invention, the microwave plasma reaction apparatus further includes: a controller connected to the power unit, the controller being configured to: determine a target lateral dimension of the plasma region based on the size of the wafer; move the lateral antenna laterally inward in response to the wafer being a first dimension to reduce the plasma region to its corresponding first target lateral dimension; and move the lateral antenna laterally outward in response to the wafer being a second dimension to expand the plasma region to its corresponding second target lateral dimension, wherein the second dimension is larger than the first dimension.

[0010] Furthermore, in some embodiments of the present invention, the controller is also configured to: determine a target lateral region of the plasma region based on the position of the wafer; and drive the lateral antenna to perform lateral displacement via the power unit to adjust the plasma region to the target lateral region.

[0011] Furthermore, in some embodiments of the present invention, the controller is further configured to: during the plasma deposition reaction, acquire the thickness of the deposited film in each region of the wafer surface; in response to the existence of a first local region having a thickness less than a lower limit of the film thickness threshold, move the first lateral antenna corresponding to the first local region in the circumferential direction laterally inward to increase the plasma density of the first local region; and in response to the existence of a second local region having a thickness greater than an upper limit of the film thickness threshold, move the second lateral antenna corresponding to the second local region in the circumferential direction laterally outward to decrease the plasma density of the second local region.

[0012] Furthermore, in some embodiments of the present invention, the interior of the cavity includes an upper cavity adjustment plate and / or a lower cavity adjustment plate, wherein at least one of the upper cavity adjustment plate and the lower cavity adjustment plate moves up and down to adjust the internal dimensions of the cavity to correspond to different cavity resonant frequencies.

[0013] Furthermore, in some embodiments of the present invention, the upper cavity adjustment plate is a liftable spray plate to adjust the spatial size of the upper half cavity inside the inner cavity, wherein a second sealing ring is provided between the outer ring of the spray plate and the side wall of the inner cavity to seal the inner cavity space during the lifting and lowering of the spray plate.

[0014] Furthermore, in some embodiments of the present invention, the interior of the cavity further includes a liftable and / or rotatable deposition stage to adapt the deposition stage to the regional position of the plasma region.

[0015] Furthermore, in some embodiments of the present invention, one or more of the spray plate, the lateral antenna, the deposition stage, and the inner cavity are provided with water-cooling channels.

[0016] Furthermore, the thin film deposition method described above according to the second aspect of the present invention is implemented via the microwave plasma reaction apparatus described above according to the first aspect of the present invention. The thin film deposition method includes the following steps: determining a target lateral parameter of a plasma region within the cavity of the microwave plasma reaction apparatus based on the geometric parameters of the wafer; and adjusting the lateral displacement of multiple lateral antennas to adjust the lateral parameter of the plasma region to the target lateral parameter.

[0017] Furthermore, in some embodiments of the present invention, the step of determining the lateral parameters of the plasma region within the cavity of the microwave plasma reactor based on the wafer's geometric parameters includes: determining the target lateral dimension of the plasma region based on the wafer's dimensions; and / or determining the target lateral region of the plasma region based on the wafer's position.

[0018] Furthermore, according to a third aspect of the present invention, a computer-readable storage medium is provided having computer instructions stored thereon. When the computer instructions are executed by a controller, the thin film deposition method described above, as provided in the second aspect of the present invention, is implemented.

[0019] In this invention, multiple lateral antennas are arranged laterally around the circumference of the inner cavity to allow microwave energy to be injected synchronously into the inner cavity from multiple circumferential directions, forming a standing wave superimposed in multiple directions. This can excite multiple electromagnetic field modes, not only to excite plasma of a larger volume, but also to make the plasma uniformly distributed in the circumferential and lateral directions within the cavity, thereby improving the uniformity of thin film deposition on wafers of different sizes.

[0020] Furthermore, in this invention, by configuring a lateral antenna that supports lateral movement, multiple lateral antennas can be moved laterally to the optimal coupling depth position, thereby improving the coupling efficiency between microwaves and the cavity, enhancing the electromagnetic field strength within the cavity, and thus increasing the lateral size of the plasma region. Attached Figure Description

[0021] The above-described features and advantages of the present invention will be better understood after reading the following detailed description of embodiments of the present disclosure in conjunction with the accompanying drawings. In the drawings, components are not necessarily drawn to scale, and components having similar related characteristics or features may have the same or similar reference numerals.

[0022] Figure 1 A schematic diagram of the external structure of a microwave plasma reaction apparatus provided according to some embodiments of the present invention is shown.

[0023] Figure 2 A schematic diagram of the internal structure of a microwave plasma reaction device provided according to some embodiments of the present invention is shown.

[0024] Figure 3 A schematic diagram illustrating the adjustment of the film thickness deposited on the wafer surface during a plasma deposition reaction process provided according to some embodiments of the present invention is shown.

[0025] Figure 4 A schematic diagram of a water-cooling structure provided according to some embodiments of the present invention is shown.

[0026] Figure 5 A structural block diagram of a microwave plasma reaction apparatus provided according to some embodiments of the present invention is shown.

[0027] Figure 6 A flowchart of a thin film deposition method provided according to some embodiments of the present invention is shown.

[0028] Figure label: 100 Microwave Plasma Reactor; 110. Inner cavity; 111 Upper cavity; 112 Lower cavity; 113 Wave-transparent dielectric wall; 114 Observation window; 120 External cavity; 121 First sealing ring; 130 lateral antenna; 131 First transverse antenna; 132 Second transverse antenna; 140 power unit; 141 Waveguide inlet; 210 Upper cavity adjustment plate; 211 Second sealing ring; 212 First drive unit; 213 Air intake port; 220 Lower cavity adjustment plate; 230 sedimentation stage; 231 Second drive unit; 240 plasma region; 310 wafer; 311 First local region; 312 Second local region; 410 First water-cooling passage; 420 Second water-cooling passage; 430 Third water-cooling passage; 510 controller; 520 memory; Steps S610~S620 Detailed Implementation

[0029] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Although the description of the present invention is presented in conjunction with preferred embodiments, this does not mean that the features of the invention are limited to these embodiments. On the contrary, the purpose of describing the invention in conjunction with embodiments is to cover other options or modifications that may be derived based on the claims of the present invention. To provide a thorough understanding of the invention, many specific details will be included in the following description. The invention may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of the invention, some specific details will be omitted in the description.

[0030] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0031] Furthermore, the terms "upper," "lower," "left," "right," "top," "bottom," "horizontal," and "vertical" used in the following description should be understood as the orientations shown in the relevant paragraphs and accompanying drawings. These relative terms are for illustrative purposes only and do not imply that the described apparatus must be manufactured or operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0032] It is understood that although terms such as "first," "second," and "third" may be used herein to describe various components, regions, layers, and / or parts, these components, regions, layers, and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, regions, layers, and / or parts. Therefore, the first components, regions, layers, and / or parts discussed below may be referred to as second components, regions, layers, and / or parts without departing from some embodiments of the present invention.

[0033] As described above, in existing MPCVD reaction cavities, microwave antennas are typically inserted from the top and / or bottom of the cavity to inject their radiated energy axially (vertically) within the cavity. After the microwaves are reflected and superimposed within the cavity, the electromagnetic field modes are confined to an axially dominant distribution (e.g., TM). 011 TE 012 The resonant region is concentrated between the antenna and the deposition stage, typically near the deposition stage. Furthermore, the upper and / or lower ends of the MPCVD reaction chamber are usually equipped with only one longitudinal antenna, coaxial with the chamber. Because the energy injection direction is fixed axially, the distribution of electromagnetic field modes within the chamber exhibits a pattern of strong intensity in the center and weak intensity at the edges. In actual deposition processes, the wafer region near the longitudinal antenna (e.g., directly above or below it) deposits a thicker film, while the wafer region farther from the antenna deposits a thinner film. Even with multiple antennas arranged longitudinally, the electromagnetic field within the chamber is still primarily distributed along the axial direction, with significant differences in circumferential electromagnetic field intensity, making flexible circumferential adjustment of the plasma impossible. Therefore, the uniformity of the plasma and its temperature distribution is difficult to control. The uniformity of film thickness deposited using existing MPCVD reaction chambers is poor.

[0034] To address the aforementioned problems in the prior art, this invention provides a microwave plasma reaction apparatus, a thin film deposition method, and a computer-readable storage medium, which can effectively compensate for the intensity differences of the circumferential electromagnetic field within the reaction cavity, achieve uniform matching of the electromagnetic field across the entire domain, thereby improving the uniformity of the plasma distribution within the cavity and contributing to enhancing the uniformity and quality stability of the deposited thin film.

[0035] In some non-limiting embodiments, the microwave plasma reaction apparatus provided in the first aspect of the present invention can be used to implement the thin film deposition method provided in the second aspect of the present invention.

[0036] The working principle of the microwave plasma reactor described above will be described below with reference to some embodiments of thin film deposition methods. Those skilled in the art will understand that these embodiments of thin film deposition methods are merely non-limiting implementations provided by the present invention, intended to clearly demonstrate the main concepts of the invention and provide specific solutions convenient for public implementation, rather than limiting all operating methods or functions of the microwave plasma reactor. Similarly, the microwave plasma reactor is also only one non-limiting implementation provided by the present invention and does not constitute a limitation on the entities implementing the steps in these thin film deposition methods.

[0037] First, please refer to Figure 1 . Figure 1 A schematic diagram of the external structure of a microwave plasma reaction apparatus provided according to some embodiments of the present invention is shown.

[0038] Can be combined Figure 2 A shared understanding. Figure 2 A schematic diagram of the internal structure of a microwave plasma reaction device provided according to some embodiments of the present invention is shown.

[0039] like Figure 1 and Figure 2 As shown, in some embodiments of the present invention, the microwave plasma reaction device 100 may mainly include an inner cavity 110, an outer cavity 120, and multiple transverse antennas 130.

[0040] Specifically, such as Figure 2As shown, the inner cavity 110 serves as the main reaction cavity, where a wafer 310 is placed for plasma deposition. An outer cavity 120 surrounds the outer surface of the inner cavity 110. Multiple lateral antennas 130, cylindrical antennas, penetrate laterally through the sidewalls of the outer cavity 120 via waveguide inlets 141, and are circumferentially distributed outside the inner cavity 110. The lateral antennas 130 are connected to a microwave generator (not shown in the figures) via waveguides or microstrip lines. These multiple lateral antennas 130 couple microwave energy to the inner cavity 110 from multiple directions, forming a hemispherical plasma region 240 inside the inner cavity 110. Generally, the plasma size corresponding to a single antenna is limited. For example, a 915MHz antenna can only deposit approximately a 6-inch plasma sphere. Therefore, the multi-antenna design in this invention can overcome this limitation and increase the size of the plasma sphere.

[0041] Furthermore, in traditional longitudinal antenna configurations, the radiated microwaves are axially polarized. Electrons are accelerated by the electromagnetic field in a concentrated axial (vertical) direction, resulting in plasma primarily accumulating in the axial region between the antenna and the deposition stage, making it difficult to diffuse circumferentially within the cavity. Therefore, the plasma coverage is limited, failing to meet the uniform deposition requirements of large-size wafers and easily leading to deposition quality differences between the wafer center and edges. In this embodiment, multiple transverse antennas 130 are arranged laterally around the circumference of the inner cavity 110. Microwave energy can be synchronously injected into the inner cavity 110 from multiple circumferential directions, forming multi-directional superimposed standing waves that can excite various electromagnetic field modes. The radiated microwaves are transversely (e.g., radially) polarized. The direction of electron acceleration by the electromagnetic field is a combination of circumferential and transverse, driving electrons to move throughout the cavity. Based on this, the microwave plasma reaction device 100 provided by this invention can not only excite a larger volume of plasma but also ensure uniform distribution of the plasma along the circumferential and transverse directions within the inner cavity 110, thereby improving the uniformity of thin film deposition on wafers of different sizes.

[0042] Furthermore, in some embodiments, the aforementioned multiple transverse antennas 130 can be horizontally and circumferentially uniformly distributed outside the cavity 110, forming an axisymmetric structure, thereby avoiding electromagnetic field distribution deviations caused by single-direction or non-uniform circumferential injection of microwave energy. This multi-directional uniform injection method enables microwaves to form symmetrically superimposed standing waves within the cavity, thereby eliminating circumferential electromagnetic field intensity differences and ensuring that plasma uniformly covers the entire reaction cavity 110.

[0043] Furthermore, in some embodiments, the extensions of multiple transverse antennas 130 can converge at the center of the inner cavity 110. In this case, the multiple transverse antennas 130 radially penetrate the sidewall of the outer cavity 120 and are circumferentially distributed outside the inner cavity 110. This radially injected microwave energy method enables microwaves to form symmetrically superimposed standing waves within the cavity, thereby eliminating the intensity difference of the circumferential electromagnetic field.

[0044] like Figure 2 As shown, the sidewall of the inner cavity 110 is made of a wave-transparent dielectric wall 113. The wave-transparent dielectric wall 113 can be made of high-transparency, high-temperature-resistant quartz glass or ceramic. The wave-transparent dielectric wall 113 isolates the inner cavity 110 from the outer cavity 120 and allows microwave energy to efficiently penetrate into the inner cavity 110. Furthermore, a first sealing ring 121 is provided at the connection between the wave-transparent dielectric wall 113 and the inner cavity 110 and the outer cavity 120. In this embodiment, the lateral antenna 130 is disposed within the outer cavity 120 and does not extend directly into the inner cavity 110, thereby ensuring not only the vacuum seal of the inner cavity 110 but also preventing contamination from being introduced into the inner cavity 110.

[0045] Preferably, the wave-transparent medium wall 113 can be made of quartz glass. Combined with... Figure 1 It is understood that an observation window 114 may be provided on the side wall of the outer cavity 120. The observation window 114 may be a combination of quartz glass and a sealing ring. Through the observation window 114, the user can observe the environmental and temperature test results inside the inner cavity 110 at any time from the outside, which is beneficial to improving the convenience of monitoring the cavity and the environment.

[0046] Furthermore, in existing technologies, the longitudinal antenna is configured to move vertically or horizontally for tuning. However, because the energy injection direction of the longitudinal antenna is fixed, only the local electromagnetic field strength can be finely adjusted; the overall distribution trend of the electromagnetic field modes within the cavity cannot be changed by adjusting the position of the longitudinal antenna. Therefore, even with a movable longitudinal antenna, it is still difficult to achieve uniform matching of the electromagnetic field throughout the cavity, failing to meet the uniformity requirements of the deposited film thickness for wafers of different sizes.

[0047] In this regard, such as Figure 2 As shown, in some embodiments of the present invention, the microwave plasma reaction device 100 may include a power unit 140. The power unit 140 is mounted at the ends of each lateral antenna 130 and is used to drive the lateral displacement of the multiple lateral antennas 130, thereby adjusting the lateral parameters of the plasma region 240 within the cavity 110. The power unit 140 may also include a guiding device to guide the linear displacement of the lateral antennas 130 and prevent deviation during the lateral displacement process. The power unit 140 can improve the adjustment accuracy of the lateral antennas 130 during the lateral displacement process.

[0048] Specifically, combined Figure 1 and Figure 2As shown, in some embodiments, the lateral parameters of the plasma region 240 may include its lateral dimensions. When multiple lateral antennas 130 move synchronously laterally inward or outward (closer to or further away from the inner cavity 110), the size of the plasma region 240 does not change monotonically, but depends on the microwave coupling efficiency as the position of the lateral antennas 130 changes. Each lateral antenna 130 has a corresponding optimal coupling depth. As each lateral antenna 130 moves laterally from its initial position to its optimal coupling depth position, the electromagnetic field strength within the inner cavity 110 gradually increases, and the lateral dimension of the plasma region 240 increases.

[0049] For example, as the lateral antenna 130 moves laterally from a shallow initial position to the optimal coupling depth position, the lateral dimension of the plasma region 240 increases. When the initial position of the lateral antenna 130 is too close to the outer cavity 120 (i.e., the lateral antenna 130 is inserted too shallowly into the outer cavity 120), microwave energy cannot be effectively fed into the resonant inner cavity 110. At this time, the electromagnetic field strength inside the inner cavity 110 is weak, and the plasma region 240 is also small. As multiple lateral antennas 130 move synchronously towards the inner cavity 110 (the coupling depth of the lateral antennas 130 increases), when the optimal coupling depth position is reached, the coupling efficiency between the microwave and the inner cavity 110 gradually increases. The electromagnetic field strength inside the inner cavity 110 increases, and the lateral dimension of the plasma region 240 increases accordingly.

[0050] Furthermore, as the lateral antenna 130 continues to penetrate deeper from the optimal coupling depth position, the lateral dimension of the plasma region 240 begins to decrease. When the lateral antenna 130 moves beyond the optimal coupling depth position, the situation reverses. Excessive insertion disrupts the resonant modes within the cavity 110, leading to electromagnetic field distortion or increased microwave energy reflection. At this point, the plasma region 240 not only fails to continue expanding but also contracts due to decreased energy transfer efficiency, and may even become unstable or extinguish.

[0051] In other embodiments, the lateral parameters of the plasma region 240 may include its lateral area. When the initial position of the plasma region 240 formed within the cavity 110 deviates from the position of the deposition stage 230, the power unit 140 can drive several (e.g., one or more) lateral antennas 130 to perform lateral displacement. In this embodiment, by lateral displacement of at least one lateral antenna 130, the lateral area of ​​the plasma region 240 can be adjusted to be aligned with the position of the deposition stage 230. After the lateral area of ​​the plasma region 240 is aligned with the position of the deposition stage 230, it helps to deposit a uniform thin film on the surface of the wafer 310.

[0052] In other embodiments, the lateral parameters of the plasma region 240 may also include plasma density. This can be combined with... Figure 3 A shared understanding. Figure 3A schematic diagram illustrating the adjustment of the film thickness deposited on the wafer surface during a plasma deposition reaction process provided according to some embodiments of the present invention is shown.

[0053] like Figure 3 As shown, in some embodiments, during the plasma deposition reaction, the thickness of the deposited film in each region of the wafer 310 surface can be obtained using a detection device. Optionally, the detection device can be an in-situ online sensor, such as a Quartz Crystal Microbalance (QCM) or a laser interferometer in-situ monitoring instrument. Alternatively, the detection device can be an offline measurement sensor, such as a spectroscopic ellipsometer or a spectroscopic reflectometer.

[0054] Continue as Figure 3 As shown, when a local region on the surface of wafer 310, such as the first local region 311, is detected to have a thinner thickness, the first lateral antenna 131, which is closest to the first local region 311 in the circumferential direction, can be moved laterally inward (the direction of movement is shown by the arrow) to increase the plasma density of the first local region 311. Conversely, when a local region on the surface of wafer 310, such as the second local region 312, is detected to have a thicker thickness, the second lateral antenna 132, which is closest to the second local region 312 in the circumferential direction, can be moved laterally outward (the direction of movement is shown by the arrow) to decrease the plasma density of the second local region 312.

[0055] Please continue to return Figure 2 In some embodiments of the present invention, the interior of the inner cavity 110 may include an upper cavity adjustment plate 210 and / or a lower cavity adjustment plate 220. At least one of the upper cavity adjustment plate 210 and the lower cavity adjustment plate 220 can move up and down to adjust the internal dimensions of the inner cavity 110. Here, the "internal dimensions of the inner cavity 110" refers to the dimensions of the reaction space. For microwaves to form a strong standing wave within the inner cavity 110, resonance conditions must be met. That is, the internal dimensions of the inner cavity 110 need to match the microwave wavelength. If the two do not match, a large amount of microwave reflection will occur, making it impossible to form a strong electric field inside the inner cavity 110. Under a weak electric field, the formed plasma region 240 is not only small but also unstable. The internal dimensions of a traditional reaction cavity are fixed, resulting in an unadjustable resonant frequency. In actual processes, changes in process gases, pressures, temperatures, plasma loads, etc., will deviate from the actual resonant point. At this time, the cavity cannot follow the matching, which can easily lead to problems such as weakened standing waves, decreased electric fields, plasma shrinkage, or even extinction.

[0056] In this embodiment, by adjusting the positions of the upper cavity adjustment plate 210 and / or the lower cavity adjustment plate 220, the internal dimensions of the inner cavity 110 can be changed, thereby corresponding to different cavity resonant frequencies. Specifically, by adjusting the position of the upper cavity adjustment plate 210, the spatial dimensions of the upper half cavity 111 within the inner cavity 110 can be adjusted. By adjusting the position of the lower cavity adjustment plate 220, the spatial dimensions of the lower half cavity 112 within the inner cavity 110 can be adjusted. Optionally, the positions of the upper cavity adjustment plate 210 and the lower cavity adjustment plate 220 can be adjusted together to adjust the overall spatial dimensions of the inner cavity 110.

[0057] Furthermore, such as Figure 2 As shown, in some preferred embodiments, the upper cavity regulating plate 210 can be configured as a liftable spray plate. An air inlet 213 is provided on the upper part of the spray plate. Process gas enters the area above the spray plate through the air inlet 213 and then enters the reaction space of the inner cavity 110 through air outlets (not shown in the figures) distributed on the lower surface of the spray plate. The multiple air outlets on the lower surface of the spray plate can improve the magnitude and uniformity of the output airflow. Furthermore, an exhaust port (not shown in the figures) is provided at the lower end and / or side end of the inner cavity 110 to extract reaction byproducts from the cavity after the process is completed.

[0058] Continue as Figure 2 As shown, the spray disk can integrate a first drive unit 212. Driven by the motor of the first drive unit 212, the spray disk can be moved up and down, thereby adjusting the spatial dimensions of the upper cavity 111. In this embodiment, the liftable spray disk simultaneously enables the air intake function of the inner cavity 110 and the adjustment function of the cavity size, making the internal structure of the inner cavity 110 more compact. By adjusting the position of the spray disk up and down, the process gap between the spray disk and the lower deposition stage 230 can be changed, thereby adjusting the diffusion degree of the gas flow field between the process gaps, and thus affecting the plasma morphology within the cavity. Furthermore, as a metal conductor, the up and down displacement of the spray disk can change the equivalent electrical dimensions and resonant frequency of the cavity, causing the resonant coupling point to move up and down, thereby affecting the center position and distribution of the plasma region 240.

[0059] In some embodiments, a second sealing ring 211 may be provided between the outer ring of the spray disc and the side wall of the inner cavity 110 to seal the space of the inner cavity 110 during the lifting and lowering of the spray disc. For example, the second sealing ring 211 may be installed on the spray disc. Further, the second sealing ring 211 may be a polytetrafluoroethylene (PTFE) sealing ring (commonly known as "Teflon"). The PTFE second sealing ring 211 has self-lubricating properties, which can achieve the sealing function while ensuring the smooth up and down movement of the spray disc.

[0060] Continue as Figure 2As shown, further, in some embodiments, the deposition stage 230 inside the inner cavity 110 may have a lifting and / or rotating function. The deposition stage 230 may integrate a second drive unit 231. Driven by the motor of the second drive unit 231, the deposition stage 230 can be moved vertically and / or rotated to adapt its position to the region of the plasma region 240. For example, when the longitudinal position of the plasma region 240 is higher than the deposition stage 230, the deposition stage 230 can be moved upwards appropriately to match its position with the plasma region 240.

[0061] In some optional embodiments, the deposition stage 230, the spray plate (upper cavity adjustment plate 210), and the lower cavity adjustment plate 220 can be adjusted individually or in conjunction. By changing the internal dimensions of the cavity, the position of the resonant coupling point is changed, thereby adjusting the cavity resonant frequency. When the coupling between microwave energy and plasma is poor (e.g., plasma region 240 is not in the optimal ignition position, plasma density is low, etc.), the above-mentioned individual or conjunction adjustment can quickly change the internal dimensions of the inner cavity 110, thereby quickly finding the optimal coupling point between the microwave electromagnetic field and the plasma, so that the plasma region 240 returns to the optimal ignition position, thereby increasing the plasma density. Compared with the prior art, which requires trying to replace various components of different sizes within the inner cavity 110 to adjust to the optimal coupling frequency, the present invention can improve the process debugging speed.

[0062] Those skilled in the art will understand that the coordinated displacement of at least two of the aforementioned deposition stage 230, spray plate (upper cavity adjustment plate 210), and lower cavity adjustment plate 220 can be adjusted synchronously or individually. For example, the position of the spray plate (upper cavity adjustment plate 210) can be adjusted first, and then it can be determined whether the current resonant coupling point has reached the optimal coupling position. If it has not reached the optimal position, the spray plate (upper cavity adjustment plate 210) and / or the lower cavity adjustment plate 220 and / or the deposition stage 230 can be moved for further adjustment. The adjustment sequence of the coordinated displacement of the multiple components within the aforementioned inner cavity 110 is not limited by the present invention.

[0063] Continue as Figure 2 As shown, to further improve the uniformity of the deposited film, during the plasma deposition reaction, the second driving unit 231 can drive the deposition stage 230 to rotate, thereby causing the wafer to rotate at a uniform speed. At this time, even if the density of the plasma region 240 above the wafer is not uniform, the deposition stage 230 with the rotating function can still ensure that the thin film can be uniformly deposited on the wafer surface.

[0064] Furthermore, in some embodiments, a spiral gasket (not shown in the figures) may be installed between the cavity 110 and the deposition stage 230. Since microwaves can only form a closed resonant cavity, if the deposition stage 230 moves up and down, causing a gap between it and the cavity 110, microwaves will leak outwards. Therefore, in this embodiment, during the up and down movement of the deposition stage 230, the spiral gasket, relying on its own elasticity, continuously presses the cavity 110 and the deposition stage 230 together, ensuring a continuous, gapless conductive contact and preventing gaps from appearing due to the displacement of the deposition stage 230. By providing the spiral gasket, the microwave leakage path can be blocked, ensuring the resonant sealing of the cavity 110 and thus maintaining stable plasma operation within the cavity 110.

[0065] Next, please refer to Figure 4 . Figure 4 A schematic diagram of a water-cooling structure provided according to some embodiments of the present invention is shown.

[0066] During plasma deposition in the microwave plasma reactor 100, the plasma is at a high temperature. This high-temperature plasma continuously radiates a large amount of heat to the spray plate, the transverse antenna 130, the inner wall of the cavity 110, and the deposition stage 230. If heat dissipation is uneven, localized overheating can easily occur. Once these components overheat, thermal expansion occurs, leading to minute changes in their dimensions. Many of these components (such as the spray plate and the transverse antenna 130) are precision microwave coupling devices; their shape, position, and flatness directly determine the electric field distribution, resonant frequency, and coupling efficiency. Localized thermal expansion of these devices causes minute deformations, warping, and displacement, effectively altering the cavity's electrical dimensions and leading to resonance mismatch, electric field distortion, and problems such as plasma shift, shrinkage, and instability.

[0067] In some embodiments, water-cooling channels may be provided inside one or more of the spray plate, lateral antenna 130, deposition stage 230, and inner cavity 110 to improve the heat dissipation uniformity of the devices within the cavity. For example... Figure 4 As shown, a first water-cooling channel 410 can be provided on the inner wall of the inner cavity 110. A second water-cooling channel 420 can be provided inside the spray plate. A third water-cooling channel 430 can be provided inside the deposition stage 230.

[0068] Furthermore, the structure of the water-cooling channels inside different devices can be adapted to the shape of the devices. For example, the first water-cooling channel 410, the second water-cooling channel 420, and the third water-cooling channel 430 can preferably be a porous mesh water-cooling structure. The porous mesh water-cooling channel helps to improve the planar heat dissipation capability of the surface of the inner cavity 110, the surface of the spray plate, and the surface of the deposition stage 230. The fourth water-cooling channel (not shown in the figure) located inside the transverse antenna 130 can preferably be a straight hole structure water-cooling channel. In this embodiment, by setting up the water-cooling channels, uniform heat dissipation can be achieved throughout the device inside the inner cavity 110, avoiding changes in device size caused by thermal expansion due to local overheating.

[0069] In addition, the deposition stage 230, which can automatically lift and rotate, can be integrated with a rotary sealing mechanism to ensure the water and gas sealing requirements of the deposition stage 230.

[0070] Next, please refer to Figure 5 . Figure 5 A structural block diagram of a microwave plasma reaction apparatus provided according to some embodiments of the present invention is shown.

[0071] like Figure 5 As shown, in some non-limiting embodiments, the microwave plasma reaction apparatus 100 of the present invention may further include a controller 510. The controller 510 may be connected to the power unit 140 for controlling it.

[0072] Specifically, in some optional embodiments, the controller 510 can be configured to perform the following steps. First, the size of the wafer to be processed is obtained. Based on the wafer size, the target lateral size of the plasma region 240 is determined. When the wafer is of a first size, the controller 510 can control one or more lateral antennas 130 to move laterally inward to converge and shrink the plasma region 240 to its corresponding first target lateral size. When the wafer is of a second size larger than the first size, the controller 510 can control the lateral antennas 130 to move laterally outward to expand and increase the plasma region 240 to its corresponding second target lateral size. In this invention, based on the above-mentioned multi-directional lateral antenna coupling technology, the lateral size (i.e., coverage area) of the plasma region 240 can be flexibly adjusted to adapt to the uniform deposition requirements of wafers of different sizes.

[0073] Furthermore, by arranging a large number of lateral antennas 130 around the outside of the cavity 110, 12-inch thin film deposition can be achieved. By changing the size and shape of the substrate of the deposition stage 230, it is possible to accommodate wafers of various sizes up to 12 inches.

[0074] As can be seen from the above embodiments, the microwave plasma reaction device 100 provided by the present invention can be compatible with the deposition of wafers of various sizes without changing the cavity size and microwave frequency of the inner cavity 110. This not only improves the compatibility of the device with wafers of different sizes, but also effectively improves the quality and purity of the thin film deposition and increases the deposition rate of the thin film.

[0075] Furthermore, in some alternative embodiments, the controller 510 can be configured to perform the following steps. First, a target lateral region of the plasma region 240 is determined based on the wafer's position. Optionally, the wafer's position can be determined by the position of the deposition stage 230. Subsequently, a plurality of lateral antennas 130 are driven to perform lateral displacement via the power unit 140 to adjust the plasma region 240 to the target lateral region. Aligning the lateral region of the plasma region 240 with the position of the deposition stage 230 helps the plasma region 240 to completely cover the wafer surface, thereby facilitating the deposition of a uniform thin film on the wafer surface.

[0076] In some alternative embodiments, the controller 510 may also be configured to perform the following steps. This can be combined with... Figure 3 For common understanding, firstly, during the plasma deposition reaction, once the plasma region 240 is located at the center of the deposition stage 230, the thickness of the deposited film in each region on the surface of the wafer 310 can be further obtained. When the thickness of a first local region 311 is less than the lower limit of the film thickness threshold, the first lateral antenna 131 corresponding to the first local region 311 in the circumferential direction can be moved laterally inward (the direction of movement is shown by the arrow) to increase the plasma density of the first local region 311. When the thickness of a second local region 312 is greater than the upper limit of the film thickness threshold, the second lateral antenna 132 corresponding to the second local region 312 in the circumferential direction can be moved laterally outward (the direction of movement is shown by the arrow) to decrease the plasma density of the second local region 312.

[0077] Back Figure 5 As shown, in some embodiments, the microwave plasma reaction apparatus 100 described above may further include a memory 520. Here, the memory 520 includes, but is not limited to, the computer-readable storage medium provided in the third aspect above, on which computer instructions are stored. The controller 510 is connected to the memory 520 and configured to execute the computer instructions stored in the memory 520 to implement the thin film deposition method as provided in the second aspect of the invention.

[0078] Next, please refer to Figure 6 . Figure 6 A flowchart of a thin film deposition method provided according to some embodiments of the present invention is shown.

[0079] like Figure 6As shown, in some embodiments of the present invention, the thin film deposition method may include steps S610 to S620. Step S610: Determine the target lateral parameters of the plasma region within the cavity of the microwave plasma reactor based on the wafer's geometric parameters.

[0080] Specifically, in some optional embodiments, the geometric parameters of the wafer may include wafer size parameters and position parameters. Therefore, during the execution of step S610, the target lateral dimension of the plasma region 240 can be determined based on the wafer size. Optionally, the target lateral region of the plasma region 240 can be determined based on the wafer position.

[0081] Next, step S620 can be performed: adjust the lateral displacement of the multiple lateral antennas to adjust the lateral parameters of the plasma region to the target lateral parameters. The specific adjustment method is as described above and will not be repeated here.

[0082] Furthermore, in some optional embodiments, the lateral parameters of the plasma region 240 may also include plasma density. Specifically, during the plasma deposition reaction, the thickness of the deposited film in each region of the wafer 310 surface can be obtained by a detection device. When a local region on the wafer 310 surface is detected to have a thickness that is too small or too large, the plasma density in that local region can be increased or decreased by moving the lateral antenna corresponding to that local region laterally in the circumferential direction inward or outward.

[0083] This concludes the basic introduction of the microwave plasma reaction apparatus provided in the first aspect of the present invention and the thin film deposition method provided in the second aspect of the present invention.

[0084] In some non-limiting embodiments, a third aspect of the invention provides the aforementioned computer-readable storage medium having a computer program product stored thereon. The computer program product includes computer instructions. A controller is connected to the memory and configured to execute the computer instructions included in the computer program product to implement the thin film deposition method provided in the second aspect of the invention.

[0085] In summary, the present invention provides a microwave plasma reaction apparatus, a thin film deposition method, and a computer-readable storage medium, which can effectively compensate for the intensity difference of the circumferential electromagnetic field in the reaction cavity, achieve uniform matching of the electromagnetic field in the whole domain, thereby improving the uniformity of plasma distribution in the cavity and helping to improve the uniformity and quality stability of the deposited thin film.

[0086] Although the methods described above are illustrated and depicted as a series of actions for the sake of simplicity, it should be understood and appreciated that these methods are not limited by the order of the actions, as some actions may occur in a different order and / or concurrently with other actions from the illustrations and descriptions herein or not illustrated and described herein but which may be understood by those skilled in the art, according to one or more embodiments.

[0087] Those skilled in the art will further appreciate that the various illustrative logic blocks, modules, circuits, and algorithm steps described in conjunction with the embodiments disclosed herein can be implemented as electronic hardware, computer software, or a combination of both. To clearly illustrate this interchangeability between hardware and software, the various illustrative components, blocks, modules, circuits, and steps are described above in a generalized manner in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. Those skilled in the art may implement the described functionality in different ways for each specific application, but such implementation decisions should not be construed as departing from the scope of the invention.

[0088] The various illustrative logic modules and circuits described in conjunction with the embodiments disclosed herein may be implemented or performed using a general-purpose controller, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. The general-purpose controller may be a microprocessor, but in alternatives, it may be any conventional processor, microcontroller, or state machine. The controller may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors cooperating with a DSP core, or any other such configuration.

[0089] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a controller, or in a combination of both. The software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the controller so that the controller can read and write information from / to the storage medium. In an alternative, the storage medium may be integrated into the controller. The controller and storage medium may reside in an ASIC. The ASIC may reside in a user terminal. Alternatively, the controller and storage medium may reside as discrete components in the user terminal.

[0090] In one or more exemplary embodiments, the described functionality may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software as a computer program product, the functionality may be stored or transmitted as one or more instructions or code on or through a computer-readable medium. A computer-readable medium includes both computer storage media and communication media, encompassing any medium that facilitates the transfer of a computer program from one location to another. A storage medium may be any available medium accessible to a computer. By way of example and not limitation, such a computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disc storage, disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and is accessible to a computer. Any connection is also legitimately referred to as a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of a medium. As used in this article, disk and disc include compact discs (CDs), laser discs, optical discs, digital multi-purpose discs (DVDs), floppy disks, and Blu-ray discs. Disks typically reproduce data magnetically, while discs reproduce data optically using lasers. Combinations of these should also be included within the scope of computer-readable media.

[0091] The prior description of this disclosure is provided to enable any person skilled in the art to make or use this disclosure. Various modifications to this disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not intended to be limited to the examples and designs described herein, but should be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A microwave plasma reaction device, characterized in that, include: The inner cavity contains a wafer for plasma deposition reactions. The outer cavity surrounds the outer part of the inner cavity; as well as Multiple lateral antennas extend laterally through the sidewalls of the outer cavity and are circumferentially distributed outside the inner cavity to couple microwave energy into the inner cavity from multiple directions, forming a plasma region. These lateral antennas are allowed to move laterally to an optimal coupling depth. When a first local region with a thickness less than the lower limit of the film thickness threshold exists on the wafer surface, the first lateral antenna closest to the first local region in the circumferential direction moves laterally inward to increase the plasma density of the first local region. When a second local region with a thickness greater than the upper limit of the film thickness threshold exists on the wafer surface, the second lateral antenna closest to the second local region in the circumferential direction moves laterally outward to decrease the plasma density of the second local region.

2. The microwave plasma reaction device as described in claim 1, characterized in that, include: A power unit, installed at the end of each of the lateral antennas, is used to drive the lateral displacement of the multiple lateral antennas and adjust the lateral parameters of the plasma region.

3. The microwave plasma reaction device as described in claim 2, characterized in that, Also includes: A controller, connected to the power unit, is configured to: The target lateral dimension of the plasma region is determined based on the dimensions of the wafer; In response to the wafer being of a first size, the lateral antenna is moved laterally inward to reduce the plasma region to its corresponding first target lateral size; and In response to the wafer being of a second size, the lateral antenna is moved laterally outward to expand the plasma region to its corresponding second target lateral size, wherein the second size is larger than the first size.

4. The microwave plasma reaction apparatus as described in claim 3, characterized in that, The controller is also configured to: Based on the position of the wafer, the target lateral region of the plasma region is determined; and The power unit drives the lateral antenna to perform lateral displacement in order to adjust the plasma region to the target lateral region.

5. The microwave plasma reaction apparatus as described in claim 3, characterized in that, The controller is also configured to: During the plasma deposition reaction, the thickness of the deposited film in each region of the wafer surface is obtained; In response to the existence of a first local region with a thickness less than the lower limit of the film thickness threshold, the first transverse antenna corresponding to the first local region in the circumferential direction is moved laterally inward to increase the plasma density of the first local region. as well as In response to the existence of a second local region whose thickness is greater than the upper limit of the film thickness threshold, the second transverse antenna corresponding to the second local region in the circumferential direction is moved laterally outward to reduce the plasma density of the second local region.

6. The microwave plasma reaction apparatus as described in claim 1, characterized in that, The interior of the cavity includes an upper cavity adjustment plate and / or a lower cavity adjustment plate, wherein at least one of the upper cavity adjustment plate and the lower cavity adjustment plate can move up and down to adjust the internal dimensions of the cavity to correspond to different cavity resonant frequencies.

7. The microwave plasma reaction apparatus as described in claim 6, characterized in that, The upper cavity adjustment plate is a liftable spray plate to adjust the space size of the upper half cavity inside the inner cavity. A second sealing ring is provided between the outer ring of the spray plate and the side wall of the inner cavity to seal the inner cavity space during the lifting and lowering of the spray plate.

8. The microwave plasma reaction apparatus as described in claim 7, characterized in that, The interior of the cavity also includes a liftable and / or rotatable deposition stage to adapt to the regional position of the plasma region.

9. The microwave plasma reaction apparatus as described in claim 8, characterized in that, The spray plate, the transverse antenna, the deposition stage, and one or more of the inner cavity are provided with water-cooling channels.

10. A thin film deposition method, characterized in that, The thin film deposition method, implemented via the microwave plasma reaction apparatus as described in any one of claims 1 to 9, comprises the following steps: Based on the wafer's geometric parameters, the target lateral parameters of the plasma region within the cavity of the microwave plasma reactor are determined; and Adjust the lateral displacement of multiple lateral antennas to adjust the lateral parameters of the plasma region to the target lateral parameters.

11. The thin film deposition method as described in claim 10, characterized in that, The step of determining the target lateral parameters of the plasma region within the cavity of the microwave plasma reactor based on the wafer's geometric parameters includes: Determine the target lateral dimension of the plasma region based on the dimensions of the wafer; and / or The target lateral region of the plasma zone is determined based on the position of the wafer.

12. A computer-readable storage medium storing computer instructions thereon, characterized in that, When the computer instructions are executed by the controller, the thin film deposition method as described in claim 10 or 11 is implemented.

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