Physical vapor deposition equipment and deposition method

Abstract

The invention provides physical vapor deposition equipment and a deposition method. The equipment comprises a reaction chamber; the target material and the wafer are oppositely arranged at two ends of the reaction chamber and are respectively used for providing a deposition material and forming a deposition material layer; the plurality of magnetic field generating devices are positioned in the reaction chamber, are arranged around the reaction chamber and are used for generating a local magnetic field in the internal space of the reaction chamber; and the control system is connected to the magnetic field generating device and is configured to control the magnetic field generating device to adjust the spatial distribution of the magnetic field in the reaction chamber. According to the technical scheme, the magnetic field intensity and direction of the magnetic field generating device are dynamically adjusted, plasma distribution is optimized, the film forming uniformity of the thin film is improved, the method is particularly suitable for large-area wafers and deposition surfaces of complex structures, the device performance problem caused by uneven thickness is reduced, and the device performance is improved. And the service life and the use performance of the product are obviously improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor manufacturing, and in particular to a physical vapor deposition device and a deposition method. BACKGROUND

[0002] In the semiconductor manufacturing process, physical vapor deposition (PVD) is widely used as a key technology to precisely deposit various functional thin films on the surface of a semiconductor substrate. Titanium nitride (TiN) thin films play an extremely important role in semiconductor devices due to their excellent physical and chemical properties, such as high hardness, good wear resistance, excellent electrical conductivity, and outstanding chemical stability.

[0003] In very large scale integrated circuits, non-uniformity in the thickness of titanium nitride thin films can cause inconsistencies in the resistance of metal interconnection lines, thereby affecting the signal transmission speed and stability of the entire circuit, and in severe cases, may even cause circuit failure; in power semiconductor devices, non-uniformity in the composition of the thin film can cause fluctuations in key parameters such as the on-resistance and breakdown voltage of the device, reducing the power handling capability and reliability of the device. Therefore, the uniformity of the thin film is a core indicator that determines the performance, yield, and reliability of the device. However, as the performance of the thin film improves, the need for precise control of the thin film manufacturing process also becomes increasingly stringent. Therefore, it is necessary to provide a technical solution that can improve the uniformity of the thin film thickness. SUMMARY

[0004] In view of the defects and deficiencies in the prior art, the present application provides a physical vapor deposition device and a deposition method to solve at least one or more of the above technical problems.

[0005] In a first aspect, the present application provides a physical vapor deposition device, comprising at least:

[0006] a reaction chamber;

[0007] a target material and a wafer, oppositely arranged at two ends of the reaction chamber, respectively used to provide deposition material and form a deposition material layer;

[0008] a plurality of magnetic field generating devices, located inside the reaction chamber and arranged around the reaction chamber, used to generate a local magnetic field in the internal space of the reaction chamber;

[0009] a control system connected to the magnetic field generating devices, the control system being configured to control the magnetic field generating devices to adjust the spatial distribution of the magnetic field inside the reaction chamber. By arranging multiple independent magnetic field generating devices around the reaction chamber and uniformly controlling them by the control system, local adjustment of the spatial distribution of the magnetic field in the deposition area is achieved, thereby improving the sputtering uniformity and the uniformity of the thin film thickness.

[0010] In some embodiments, a thickness monitoring system is further included for measuring the thickness of the deposited film on the wafer surface in real time and feeding back the measurement results to the control system, which adjusts the magnetic field generating device according to the measurement results. The real-time thickness of the deposited film as a feedback signal can timely correct the thickness non-uniformity problem in the deposition process, improve the control accuracy and process stability, and ensure the uniformity of the finally formed film.

[0011] In some embodiments, the control system is configured to independently adjust the parameters of at least one magnetic field generating device corresponding to a specific area of the wafer surface when detecting that the film thickness in the area is non-uniform, for local magnetic field correction. When detecting that a specific area of the wafer has thickness abnormality, only the magnetic field generating device corresponding to the area can be adjusted without affecting other normal areas.

[0012] In some embodiments, the magnetic field generating device is an electromagnetic coil, and the control system adjusts the magnetic field strength and direction by adjusting the current size and direction of the electromagnetic coil. The magnetic field strength and direction of the electromagnetic coil can be accurately controlled by the current.

[0013] In some embodiments, each magnetic field generating device includes at least two electromagnetic sub-coils stacked vertically in space, and the current direction and size of each electromagnetic sub-coil can be independently adjusted. By vertically stacking and independently controlling the sub-coils, the gradient or specific profile of the magnetic field in the height direction of the reaction chamber can be shaped. The overall uniformity from the center to the edge can be more effectively optimized, making the magnetic field adjustment more flexible and rapid.

[0014] In some embodiments, the magnetic field generating device is perpendicular to the surface of the wafer, and the length of the magnetic field generating device accounts for at least 1 / 4 of the effective height of the reaction chamber; in the overhead direction of the reaction chamber, the magnetic field generating device is located in the outer region of the wafer. The magnetic field generating device is perpendicular to the wafer surface and located in the outer region of the wafer, which ensures the effective confinement of the magnetic field on the plasma while avoiding direct interference with the wafer.

[0015] In some embodiments, a height adjusting device is further included for adjusting the height of the magnetic field generating device in the reaction chamber; the height adjusting device is connected with the control system, and the control system is configured to control the height adjusting device to adjust the working height of the magnetic field generating device according to the feedback of the thickness monitoring system. The height-adjustable function of the magnetic field generating device allows the magnetic field action area to be flexibly matched according to different process requirements, improving the process adaptability of the equipment.

[0016] In some embodiments, the magnetic field generator is rotatably mounted around the central axis of the reaction chamber, and the control system is further configured to control the rotational speed and direction of the magnetic field generator. Adjusting the rotational speed and direction through the control system further optimizes the magnetic field distribution and improves the uniformity of the thin film.

[0017] In some embodiments, a first magnet array is disposed on the back side of the target material. The first magnet array is used to generate a primary magnetic field to confine the plasma on the target surface. The first magnet and the magnetic field generating device work together to achieve precise control of the film uniformity through the cooperation of a composite magnetic field system of primary confinement and secondary regulation, ensuring efficient deposition.

[0018] Secondly, this application provides a physical vapor deposition method, employing the physical vapor deposition equipment provided by any of the above technical solutions, the method comprising:

[0019] The physical vapor deposition process is initiated within the reaction chamber;

[0020] During the material deposition process on the wafer surface, the thickness of the deposited thin film on the wafer surface is monitored in real time;

[0021] When the difference in film thickness between the central region and the edge region of the wafer surface exceeds a threshold, the control system adjusts the current intensity and current direction of the magnetic field generator to dynamically adjust the magnetic field intensity and / or direction inside the reaction chamber, thereby confining the plasma to diffuse uniformly on the wafer surface and improving the uniformity of film thickness deposited on the wafer surface.

[0022] Compared with the prior art, the physical vapor deposition equipment and deposition method provided in this application have the following advantages:

[0023] The physical vapor deposition (PVD) equipment provided in this application optimizes plasma distribution and improves film uniformity by dynamically adjusting the magnetic field strength and direction of the magnetic field generator, making it particularly suitable for large-area wafers and complex deposition surfaces. This PVD method monitors the thickness differences of the material layer deposited on the wafer surface in real time and feeds the results back to the control system. The control system adjusts the parameters of the magnetic field generator according to a preset program, enabling timely correction of thickness inhomogeneity issues during deposition. This dynamic adjustment of the deposition process significantly improves film uniformity, reduces device performance problems caused by thickness inhomogeneity, and significantly enhances product lifespan and performance. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a thin film deposition apparatus in the prior art;

[0025] Figure 2a andFigure 2b This is a thermogram corresponding to uneven film thickness in the prior art;

[0026] Figure 3 This is a schematic diagram of the internal structure of the deposition apparatus provided in Embodiment 1 of this application;

[0027] Figure 4 This is a top view of the deposition apparatus provided in Embodiment 1 of this application;

[0028] Figure 5 This is a flowchart of the deposition method provided in Embodiment 2 of this application.

[0029] Explanation of reference numerals in the attached figures:

[0030] 100. Reaction chamber; 200. Thickness monitoring system; 300. Control system; 400. First magnet array; 500. Magnetic field generating device; 510. Upper sub-coil; 520. Lower sub-coil; 600. Height adjustment device. Detailed Implementation

[0031] In metal interconnect layers, titanium nitride films can act as diffusion barrier layers to prevent the diffusion of metal atoms, ensuring stable electrical performance of devices. On the contact electrodes of integrated circuits, titanium nitride films can reduce contact resistance and improve electron transport efficiency. Titanium nitride films can be achieved using physical vapor deposition (PVD) processes; see [link to documentation]. Figure 1 Current physical vapor deposition (PVD) processes utilize ion bombardment of a target to drop target atoms and form a thin film on a wafer. Magnetron sputtering equipment typically has a fixed arrangement of permanent magnets on the back of the target to form a fixed magnetic field distribution to constrain the movement of charged particles. When the electric and magnetic fields at the target surface are perpendicular to each other, i.e., the magnetic field lines are parallel to the target surface and the electric field lines are perpendicular to the target surface, both ions and electrons will move in a spiral along the magnetic field lines, increasing the electron's travel distance and significantly increasing the number of electron collisions with neutral gas molecules. This results in more ions bombarding the target, thereby improving the coating efficiency.

[0032] See Figure 2a and Figure 2b , Figure 2a Specifically, it shows a situation where the film layer on the wafer surface exhibits a significant thickness difference from the center to the edge. Figure 2bSpecifically, this illustrates a situation where there are significant differences in the local thickness of the film layer at the edge of the wafer surface. To improve this uneven film thickness phenomenon in the prior art, this application provides a physical vapor deposition apparatus and deposition method that can precisely control the uniformity of the film layer thickness, thereby ensuring product quality reliability. The technical solution of this application is described in detail below through Embodiment 1 and Embodiment 2. Those skilled in the art can easily understand other advantages and effects of this application through the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, unless otherwise specified, the following embodiments and features in the embodiments can be combined with each other.

[0033] Example 1:

[0034] See Figure 3 and Figure 4 This embodiment provides a physical vapor deposition apparatus for depositing titanium nitride (TiN) thin films with high uniformity. The apparatus includes a reaction chamber 100, inside which a target and a wafer are disposed. The target is located at the bottom of the reaction chamber 100 for providing the deposition material, and the wafer is disposed at the top of the reaction chamber 100 relative to the target for forming the deposition material layer.

[0035] In some embodiments, the reaction chamber 100 is a cylindrical vacuum chamber with flange interfaces at the top and bottom for mounting the target assembly and wafer transport and fixing assembly, respectively. The sidewalls of the chamber have process gas inlets and vacuum outlets. Furthermore, the reaction chamber 100 is equipped with a double-layer water-cooled jacket to maintain stable chamber wall temperature during the process. Understandably, the reaction chamber 100 also includes system circuit interfaces necessary for implementing the PVD process. The physical vapor deposition equipment provided in this embodiment also includes a control system necessary for the process, such as an industrial programmable logic controller (PLC) and a connected multi-channel programmable power supply, which will not be elaborated further here.

[0036] In some embodiments, taking titanium nitride thin films as an example, high-purity (≥99.95%) metallic titanium is used as the sputtering target. The target is a circular plate, fastened to a target backing plate by bolts. Cooling water pipes are integrated inside the target backing plate to dissipate the high heat generated during sputtering and prevent overheating and deformation of the target.

[0037] In some implementations, an 8-inch wafer is used as an example. The wafer is horizontally fixed to a wafer tray located at the top of the chamber by edge clamping or adsorption. The wafer tray can integrate functions such as resistance heaters to heat the wafer to the set process temperature. Furthermore, the working surface of the target is parallel to the upper surface of the wafer, with a distance of approximately 70 mm between them. This distance can better balance the deposition rate and film uniformity. The heatable wafer tray can promote the surface migration of deposited atoms, reduce the internal stress of the film, and improve the crystal quality.

[0038] In some embodiments, the target assembly mainly includes a target and a first magnet array 400 integrated on its back side. The first magnet array 400 is used to generate a primary magnetic field to confine plasma on the target surface. Optionally, the first magnet array 400 is a neodymium iron boron (NdFeB) permanent magnet with high coercivity and high energy product, arranged in two concentric rings on the back side of the target. The polarities of the inner ring magnets are opposite to those of the outer ring magnets; for example, the N pole of the inner ring and the S pole of the outer ring magnets all face the target surface, forming a strong magnetic field region between the inner and outer rings with the magnetic field direction parallel to the target surface. The active area of ​​the first magnet array 400 is close to the target surface and is responsible for efficiently sputtering target atoms, enabling the particle stream sputtered from the target to be directed perpendicularly or approximately perpendicularly to the wafer surface.

[0039] This embodiment provides a physical vapor deposition apparatus that also includes several magnetic field generators 500. The magnetic field generators 500 are located inside a reaction chamber 100 and arranged around the reaction chamber 100 near its inner wall. The magnetic field generators 500 are used to generate a local magnetic field within the internal space of the reaction chamber 100. Optionally, each magnetic field generator 500 has a long rectangular columnar structure, with its length direction perpendicular to the wafer surface. The length of the magnetic field generator 500 is approximately half the effective working height of the reaction chamber, i.e., its height is approximately 30mm to 40mm, covering most of the plasma-critical region extending downwards from the wafer tray surface to the target surface. The surrounding arrangement allows for independent application of magnetic field influence at a 360° azimuth angle around the wafer, enabling the generated magnetic field to act most directly and efficiently on the plasma transport region above the wafer, avoiding magnetic field attenuation. The vertical mounting method, perpendicular to the wafer and target, also facilitates the generation of a more uniform local magnetic field in three-dimensional space, effectively confining the radial movement of electrons in vertical space and controlling the lateral distribution of plasma. See also Figure 4 From a top-down perspective, four magnetic field generating devices 500 are evenly arranged around the central axis of the reaction chamber 100 on the inner side wall, forming a ring magnetic field array that surrounds the outer region of the wafer.

[0040] In existing PVD deposition processes, the high-density plasma ring generated by the first magnet array 400 attenuates as it diffuses towards the wafer center. Furthermore, film stress is related to the energy of particles arriving during deposition, leading to uneven stress distribution between the wafer edge and center. The magnetic field generator 500 provides effective compensation. By independently adjusting one or more device parameters at specific locations, a corrective magnetic field can be locally generated. This alters the vertical component or gradient of the magnetic field in the wafer edge region, attracting or repelling plasma, thereby affecting the ion energy and incident angle reaching the wafer surface at that location. This counteracts the inherent inhomogeneities, resulting in a uniformly thick deposition layer. In this embodiment, the first magnet array 400 and the magnetic field generator 500 work together. Through the secondary magnetic field, the trajectory of ions in the high-electric-field region near the wafer surface is controlled, achieving uniformity of ion bombardment intensity at various points on the wafer surface. This improves the stress uniformity and density of the film. The combined magnetic field system of primary constraint and secondary control works in tandem, ensuring efficient deposition while achieving precise control over film uniformity.

[0041] In some embodiments, the control system 300 is connected to the first magnet array 400 and the magnetic field generator 500. The control system is configured to control the magnetic field generator 500 based on real-time monitoring results of the film's physical parameters, thereby adjusting the spatial distribution of the magnetic field inside the reaction chamber 100. The control system 300 can be a programmable logic controller (PLC). The PLC sends instructions to the power supplies of each channel to set the operating current of each magnetic field generator 500. See [reference needed]. Figure 4 By independently adjusting the current of the four magnetic field generators 500, magnetic field patterns with different intensities and spatial distributions can be synthesized within the reaction chamber. The control system 300 enables active control of the spatial distribution of the magnetic field. When uneven film thickness is detected in a specific area on the wafer surface, the parameters of at least one magnetic field generator 500 corresponding to that area are independently adjusted for local magnetic field correction. When an abnormal thickness is detected in a specific area of ​​the wafer, only the magnetic field generator 500 in the corresponding location can be adjusted without affecting other normal areas. For example, all devices can be set to operate at the same current to generate a uniform annular magnetic field; alternatively, two opposite devices can be set to have higher currents to generate an asymmetrical magnetic field to compensate for process asymmetry that may be caused by the location of the inlet.

[0042] The physical vapor deposition apparatus provided in this embodiment also includes a thickness monitoring system 200. The thickness monitoring system 200 is used to measure the thickness of the titanium nitride thin film deposited on the wafer surface in real time and feeds the measurement results back to the control system 300. The control system 300 adjusts the parameters of the magnetic field generating device 500 based on the measurement results. The thickness monitoring system 200 can be a device already used in the prior art, such as a spectroscopic ellipsometry, which will not be elaborated further here. Using the real-time thickness of the deposited thin film as a feedback signal can promptly correct thickness inhomogeneity problems that occur during the deposition process, improve control accuracy and process stability, and ensure the uniformity of the final thin film.

[0043] Specifically, the control system 300 receives real-time thickness data uploaded by the thickness monitoring system 200, calculates the average thickness of all measurement points at the current time point, the deviation Δt(t) between the thickness of each measurement point and the average value, and calculates the key indicator characterizing the uniformity of this measurement, namely the thickness non-uniformity NU(t). Subsequently, the control system 300 compares the deviation Δt(t) and the non-uniformity NU(t) with a preset target uniformity threshold. If NU(t) exceeds the threshold and the deviation pattern shows a uniform distribution (e.g., all edge points are thicker than the center area), the control system 300 synchronously activates all magnetic field generators 500 in the entire reaction chamber 100, sending commands to all magnetic field generators 500 to synchronously increase their operating current, for example, to... Figure 2a The thickness of the film layer is adjusted as shown. An enhanced global annular magnetic field more strongly confines the plasma, suppressing its excessive diffusion to the edges, thereby systematically correcting the film thickness difference from the center to the edge. If the NU(t) exceedance is mainly caused by anomalies at individual points, the control system 300 activates a local correction mode, independently adjusting the magnetic field generator 500 corresponding to the anomaly region. For example, increasing the magnetic field generator 500 located on the side of the chamber vacuum interface to attract more plasma enrichment, thereby precisely increasing the deposition rate of that local region and making its deposition thickness catch up with other regions, for example, for... Figure 2b The thickness of the film layer is adjusted. After each adjustment, the system waits for a fixed time period, then acquires new thickness data and re-evaluates NU(t). If the target is still not met, fine-tuning continues according to the same logic; if the target is met, the current magnetic field parameters are kept stable. Through real-time feedback compensation, the uniformity of the thin film on each wafer can be automatically corrected to the optimal range, significantly improving product yield and process capability. Optionally, based on the thickness feedback mechanism, when the thickness monitoring system 200 detects uneven thickness in a certain area, the control system 300 can also prioritize adjusting the parameters of the first magnet array 400 for a more fundamental adjustment from the source. By arranging multiple independent magnetic field generating devices around the reaction chamber in coordination with the first magnet array 400, and uniformly controlling them by the control system 300, flexible adjustment of the spatial distribution of the magnetic field in the deposition area is achieved.

[0044] In some embodiments, the magnetic field generating device 500 is an electromagnetic coil, and the control system 300 adjusts the magnetic field strength and direction by regulating the magnitude and direction of the current in the electromagnetic coil. Optionally, the core of each magnetic field generating device 500 is a hollow wound coil made of high-temperature resistant insulated copper wire, such as polyimide enameled wire. The magnetic field strength and direction of the electromagnetic coil can be precisely controlled by the current. Furthermore, the electromagnetic coil is externally encapsulated with a water-cooling jacket, and external cooling water circulation removes the heat generated by the large current passing through the coil, ensuring stable coil resistance and constant and controllable magnetic field output. The leads at both ends of each electromagnetic coil are led out of the reaction chamber 100 through connectors and connected to independent power supply channels in the control system 300. The control system 300 controls the magnetic field parameters generated by the electromagnetic coil by adjusting the magnitude and polarity of the output current of this power supply. Compared with permanent magnets, the current regulation has an extremely fast response time and can achieve continuous stepless changes in magnetic field strength, enabling the system to track and compensate for thin film thickness differences in the process in real time.

[0045] In some embodiments, each magnetic field generating device 500 includes at least two electromagnetic sub-coils stacked vertically, and the direction and magnitude of the current in each electromagnetic sub-coil can be adjusted independently. For example, each magnetic field generating device 500 includes a lower sub-coil 510 near the target material and an upper sub-coil 520 near the wafer, with a center-to-center distance of approximately 30 mm between them. The lower sub-coil 510 and the upper sub-coil 520 have completely independent electrical connections, and the number of turns they have can be the same or different, so as to affect the distribution of different vertical regions of plasma inside the reaction chamber 100 respectively. By using two vertically stacked and independently controlled sub-coils, a magnetic field gradient or specific magnetic field profile can be shaped along the height of the reaction chamber 100. This allows for more effective optimization of the overall uniformity of the thin film from the center to the edge. For example, in the early stages of the PVD process, due to the high sputtering yield of the target material and good material deposition uniformity, appropriate lower and upper magnetic fields can be set to achieve a high deposition rate and good uniformity. As the target material is consumed and grooves appear, the plasma field changes accordingly. The control system 300 can flexibly adjust the ratio of the upper and lower currents to maintain the optimal plasma distribution throughout the entire target lifespan. Understandably, the electromagnetic coil can have more sub-coils, such as adding a middle-layer sub-coil, to achieve more precise vertical layer control of the plasma region, suitable for processes with extremely high uniformity requirements. Each electromagnetic sub-coil can be arranged with non-equidistant spacing, for example, more densely arranged near the wafer to more precisely control this critical area. This makes magnetic field adjustment more flexible and rapid. Each electromagnetic sub-coil can also be arranged with equal spacing.

[0046] In some embodiments, the magnetic field generating device 500 is perpendicular to the wafer surface, and its length is at least one-quarter of the effective height of the reaction chamber 100. The effective height typically refers to the distance from the working surface of the target to the wafer surface. For example, if the effective height is 80 mm, the coil length is at least 20 mm, preferably 30 mm to 50 mm. When the magnetic field generating device 500 consists of several vertically stacked electromagnetic coils, its length refers to the length between the bottom of the lower sub-coil 520 and the top of the upper sub-coil 510. The length of the magnetic field generating device 500 covering at least one-quarter of the effective height ensures that the generated magnetic field can effectively act on the entire critical transport region extending upwards from the plasma on the upper surface of the target. If the length is too small, the generated magnetic field can only be locally corrected in a small area, potentially leading to a control blind zone in the vertical direction. Furthermore, the length of the magnetic field generating device 500 can be one-third, one-half, three-quarters, or even more of the effective height of the reaction chamber 100. A sufficiently long coil can provide a magnetic field with sufficient depth in the vertical direction, ensuring that charged particles from the wafer surface to the plasma bulk region are effectively guided and confined, generating a more uniform axial magnetic field to achieve effective control in three-dimensional space, which is especially suitable for processes that require large-scale, uniform plasma diffusion.

[0047] In some embodiments, the magnetic field generator 500 is located in the outer region of the wafer in a top view of the reaction chamber. When the magnetic field generator 500 is an electromagnetic coil, the inner diameter of the annular surrounding ring formed by the coil array is slightly larger than the diameter of the wafer. For example, for a 200mm wafer, the inner diameter of the coil array is approximately 220mm to 250mm. The magnetic field generator 500 is perpendicular to the wafer surface and located in the outer region of the wafer, ensuring effective confinement of the plasma by the magnetic field while avoiding direct interference with the wafer. The electromagnetic coil array is arranged outside the wafer projection area, so that the area of ​​action of the secondary control magnetic field it generates is spatially offset from the area of ​​action of the primary confinement magnetic field on the back of the target. This prevents the secondary magnetic field from excessively interfering with the precise distribution of the primary magnetic field on the target surface, thereby ensuring the efficiency and stability of the basic sputtering process. This allows the secondary magnetic field to act concentrated on the plasma transport and homogenization area above the wafer, resulting in more precise control and higher efficiency.

[0048] The physical vapor deposition apparatus provided in this embodiment also includes a height adjustment device 600. This height adjustment device 600 is used to adjust the height of the magnetic field generator 500 within the reaction chamber 100. The height adjustment device 600 is connected to a control system 300, which is configured to control the height adjustment device 600 to adjust the overall working height of the magnetic field generator 500 based on feedback from the thickness monitoring system 200. Optionally, the height adjustment device 600 employs a high-precision servo motor in conjunction with a ball screw mechanism. Each magnetic field generator 500 is mounted on an independent vertically guided lifting platform, which is driven by a ball screw to reciprocate up and down within the reaction chamber 100 to control the local magnetic field strength in the vertical space. It is understood that the height adjustment device 600 can also employ any mechanical device capable of achieving its lifting function, such as a linear motor or a pneumatic / hydraulic cylinder; no further limitations are imposed here. The height-adjustable function of the magnetic field generator 500 allows the strongest local magnetic field region to be aligned with the most effective application location under the current process pressure. For example, if the thickness monitoring system 200 detects that the wafer edge is generally thicker, which may indicate excessive plasma diffusion to the edge, the control system 300 receives the signal and issues a command to appropriately raise the height of all magnetic field generators 500, shifting the strong magnetic field region upwards, strengthening the confinement of the upper and middle layers of plasma, and suppressing its lateral diffusion to the edge, thereby inhibiting excessive edge deposition. When a local thin film thickness non-uniformity is detected at a specific azimuth angle, the control system 300 can adjust not only the current of the corresponding magnetic field generator 500 but also its height, making its strong magnetic field region closer to or further away from the wafer surface at that point, changing the plasma confinement and local deposition rate in the local area. The height-adjustable function of the magnetic field generator 500 allows the magnetic field application area to be flexibly matched according to different process requirements, further improving the process adaptability of the equipment.

[0049] In some embodiments, the magnetic field generating device 500 is rotatably arranged around the central axis of the reaction chamber 100, and the control system 300 is further configured to control the rotational speed and direction of the magnetic field generating device 500. All the surrounding magnetic field generating devices 500 are fixedly mounted on a ring-shaped rotating platform. The rotating platform is connected to the drive mechanism at the bottom of the chamber via a central rotating shaft or rotating guide rail. This platform is located inside the reaction chamber 100 and between the chamber sidewall and the wafer periphery. By adjusting the rotational speed and direction through the control system 300, the magnetic field distribution is further optimized, and the uniformity of the thin film is improved. The magnetic field generating device 500 can rotate clockwise or counterclockwise, and can rotate continuously at a uniform speed or reciprocate.

[0050] Example 2:

[0051] See Figure 4 to Figure 5This embodiment provides a physical vapor deposition method. The deposition method provided in this embodiment uses the physical vapor deposition equipment provided in Embodiment 1 to deposit film layers. The deposition method provided in this embodiment will be described in detail below.

[0052] S10: Initiate the physical vapor deposition process within the reaction chamber.

[0053] Specifically, the equipment is first adjusted to a ready state, and the initial current distribution of the magnetic field generator 500 is preset through the control system. For example, the current of all four coils is set to 5A and the direction is uniform. The working height of the magnetic field generator 500 is set, and then the reaction chamber 100 is evacuated to the base pressure and the process gas is introduced. For TiN film deposition, argon (Ar, sputtering gas) and nitrogen (N2, reaction gas) are introduced, with flow rates set to 50 sccm and 10 sccm, respectively. DC power is applied to the titanium target to excite argon plasma, and target pre-sputtering begins.

[0054] S20: During the material deposition process on the wafer surface, the thickness of the thin film deposited on the wafer surface is monitored in real time.

[0055] Specifically, titanium atoms react with active nitrogen atoms in the plasma to deposit a TiN thin film on the wafer surface. Simultaneously with the deposition process, a thickness monitoring system 200 integrated into the equipment, such as a spectroscopic ellipsometry, is activated. This device sequentially measures the film thickness at several preset points on the wafer surface at a frequency of once per second, and the thickness data is transmitted to the control system 300 in real time.

[0056] S30: When the difference in film thickness between the central region and the edge region of the wafer surface is detected to exceed the threshold, the control system 300 adjusts the current intensity and current direction of the magnetic field generating device 500 to dynamically adjust the magnetic field intensity and / or direction inside the reaction chamber, so as to confine the plasma to diffuse uniformly on the wafer surface and improve the uniformity of film thickness deposited on the wafer surface.

[0057] Specifically, in this process, the control system 300 identifies the non-uniformity mode based on the thickness non-uniformity NU(t) and performs dynamic magnetic field adjustment. According to a preset program, the control system 300 adjusts the current of the four magnetic field generators 500 in real time to change the magnetic field distribution in the region above the wafer, thereby guiding and confining the plasma to achieve a uniform distribution on the wafer surface, ultimately obtaining a uniformly thick TiN thin film. When the deposition reaches the target total thickness, the target power supply is turned off, and the process gas supply is stopped.

[0058] In summary, the physical vapor deposition equipment and deposition method provided in this application effectively overcome the various shortcomings of the prior art, and therefore have high industrial application value.

[0059] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A physical vapor deposition apparatus, characterized in that, At least including: Reaction chamber; The target and the wafer are disposed opposite each other at both ends of the reaction chamber, and are used to provide the deposition material and form the deposition material layer, respectively. Several magnetic field generating devices are located inside the reaction chamber and arranged around the reaction chamber, and are used to generate a local magnetic field in the internal space of the reaction chamber. A control system is connected to the magnetic field generating device, the control system being configured to control the magnetic field generating device to adjust the spatial distribution of the magnetic field inside the reaction chamber.

2. The physical vapor deposition apparatus according to claim 1, characterized in that, It also includes a thickness monitoring system, which is used to measure the thickness of the thin film deposited on the wafer surface in real time and feed the measurement results back to the control system, which adjusts the magnetic field generating device according to the measurement results.

3. The physical vapor deposition apparatus according to claim 2, characterized in that, The control system is configured to: when it detects that the film thickness is uneven in a specific area on the wafer surface, independently adjust the parameters of at least one of the magnetic field generating devices corresponding to that area to perform local magnetic field correction.

4. The physical vapor deposition apparatus according to claim 1, characterized in that, The magnetic field generating device is an electromagnetic coil, and the control system adjusts the magnetic field strength and direction by adjusting the magnitude and direction of the current in the electromagnetic coil.

5. The physical vapor deposition apparatus according to claim 4, characterized in that, Each of the magnetic field generating devices includes at least two electromagnets stacked vertically in space, and the direction and magnitude of the current in each electromagnet can be adjusted independently.

6. The physical vapor deposition apparatus according to claim 1, characterized in that, The magnetic field generating device is perpendicular to the surface of the wafer, and the length of the magnetic field generating device is at least 1 / 4 of the effective height of the reaction chamber; in the top view of the reaction chamber, the magnetic field generating device is located in the outer region of the wafer.

7. The physical vapor deposition apparatus according to claim 6, characterized in that, It also includes a height adjustment device for adjusting the height of the magnetic field generator in the reaction chamber; the height adjustment device is connected to the control system, which is configured to control the height adjustment device to adjust the working height of the magnetic field generator based on feedback from the thickness monitoring system.

8. The physical vapor deposition apparatus according to claim 1, characterized in that, The magnetic field generating device is rotatably arranged around the central axis of the reaction chamber, and the control system is further configured to control the rotation speed and rotation direction of the magnetic field generating device.

9. The physical vapor deposition apparatus according to claim 1, characterized in that, A first magnet array is provided on the back side of the target material, which is used to generate a primary magnetic field to confine the plasma on the surface of the target material.

10. A physical vapor deposition method, employing the physical vapor deposition equipment as described in any one of claims 1 to 9, characterized in that, The method includes: The physical vapor deposition process is initiated within the reaction chamber; During the material deposition process on the wafer surface, the thickness of the deposited thin film on the wafer surface is monitored in real time; When the difference in film thickness between the central region and the edge region of the wafer surface exceeds a threshold, the control system adjusts the current intensity and direction of the magnetic field generator to dynamically adjust the magnetic field intensity and / or direction inside the reaction chamber, thereby confining the plasma to diffuse uniformly on the wafer surface and improving the uniformity of the film thickness deposited on the wafer surface.

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