Magnetron components and methods for improving high-cavity film thickness uniformity and orifice filling capability

Abstract

This invention proposes a magnetron sputtering assembly and method to improve the uniformity of high-cavity film thickness and the ability to fill voids, belonging to the field of semiconductor manufacturing technology. The method involves setting an initial arrangement of the magnetron assemblies, adjusting their parameters, and performing thin film deposition on a wafer based on the magnetron assemblies with different parameters to obtain the film thickness deposited on the wafer surface. Based on the film thickness results, the film and the magnetron assemblies used in the deposition process are divided into concave and convex types. Combining the concave and convex types of magnetron assemblies yields a magnetron assembly combination with optimal film thickness uniformity. Combining half of the magnetic beads from the concave type and half of the magnetic beads from the convex type in the optimal combination, the final magnetic bead distribution and the corresponding yoke shape are obtained. Using this method, an ideal magnetron assembly structure can be obtained. Magnetron sputtering using this assembly results in high film uniformity and effectively avoids the formation of depressions and voids in the film.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor manufacturing technology, and specifically relates to a magnetron assembly and method that can improve the uniformity of high cavity film thickness and the ability to fill vias. Background Technology

[0002] Physical vapor deposition (PVD) systems are widely used in semiconductor metallization processes, particularly in device interconnects, where they can deposit adhesive layers or fill vias with Al. However, due to physical limitations, atoms cannot deposit to the bottom of the pattern (holes or trenches) in PVD systems. Increasing the height of the target from the cavity can help filter the atomic deposition path, such as... Figure 1 As shown in the right half, atoms with small deposition angles (the angle between the direction of atomic fall and the horizontal direction) will fall on the masking element of the cavity, thus leaving more atoms with large deposition angles to enter the bottom of the pattern, increasing the bottom coverage of the pattern.

[0003] To achieve better bottom coverage, a long-throw method is typically used to increase the cavity height and address the deposition angle issue. Long-throw cavities usually set the distance between the target and the wafer to be greater than 150mm, and the target-to-wafer height increases with the pattern aspect ratio to select for more perpendicularly oriented deposition atoms. However, as the cavity height increases, the uniformity of the thin film deposition eventually decreases significantly, primarily manifested as a thicker film in the wafer center and a thinner film at the edges. The wafer area in the center is significantly smaller than that in the edge regions. Figure 2 As shown, when the inner circle diameter is half the wafer diameter, the inner circle radius and the outer circle width are both R, and the area of ​​the inner circle is πR. 2 The area of ​​the outer ring region is 3πR 2 The two regions differ in area by a factor of three. Furthermore, since the sputtering areas of traditional (low-cavity) magnetron sputtering components are concentrated in the middle, the difference in film thickness between the center and the edge regions is even greater. In this case, the previous method of optimizing the uniformity of thin film thickness by adjusting the distance between the target and the wafer is completely ineffective.

[0004] Furthermore, existing magnetron design cannot guarantee that the direction of atomic deposition on the wafer is consistent. This leads to significant differences in via filling at the wafer center, middle, and edge locations, resulting in vias such as those below seal 1. Figure 3 The cavity 2 shown. By increasing the height of the cavity, enough vertical atoms can be filtered out, but simply increasing the height of the cavity will result in a significant loss of deposition rate.

[0005] like Figure 4 As shown, the different filling speeds in the three regions lead to different sealing times in different regions, which can cause void defects in AlCu filling and result in product scrap. Summary of the Invention

[0006] To address the aforementioned problems, the present invention aims to provide a magnetron assembly and method that can improve the uniformity of high cavity film thickness and the ability to fill pores, thereby enhancing the uniformity of high cavity film thickness and the ability to fill pores.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows:

[0008] A design method for magnetron components that can improve high-cavity film thickness uniformity and orifice filling capability includes the following steps:

[0009] Step 1: Set the initial arrangement of the magnetic control components. The magnetic control components include a magnetic yoke, a magnetic bead fixing component, a magnetic bead, a base plate, and a rotating fixing lock. The magnetic bead fixing component has at least four through holes for accommodating the magnetic bead.

[0010] Step 2: Adjust the magnetron assembly parameters and deposit film on the wafer based on magnetron assemblies with different parameters to obtain the film thickness deposited on the wafer surface; the magnetron assembly parameters include one or more of the following parameters: magnetic field strength, N / S spacing, imbalance between inner and outer magnetic beads, and peak region of the target erosion raceway; according to the film thickness results, the film and the magnetron assembly used in the deposition process are divided into two categories: concave and convex.

[0011] Step 3: Based on the thin film thickness results obtained in Step 2, combine the concave and convex magnetron components to obtain the magnetron component combination with the best film thickness uniformity. Combine the half of the magnetic bead distribution of the concave magnetron component and the half of the magnetic bead distribution of the convex magnetron component in the best magnetron component combination to obtain the final magnetic bead distribution and the magnetic yoke shape corresponding to the magnetic bead distribution.

[0012] Furthermore, in step 2, the thin film and the magnetron assembly used in the deposition process are classified into two categories based on the film thickness results: uneven and concave.

[0013] The difference M between the average film thickness of the outer region and the average film thickness of the inner region on the wafer is obtained. If M>0, the film thickness result is determined to be concave, and the corresponding magnetron assembly is determined to be concave. If M<0, the film thickness result is determined to be convex, and the corresponding magnetron assembly is determined to be convex.

[0014] Furthermore, in step 3, based on the thin film thickness results obtained in step 2, the combination of concave and convex magnetron components to obtain the magnetron component combination with optimal film thickness uniformity includes:

[0015] The average thicknesses of the inner and outer regions of concave thin films and the average thicknesses of the inner and outer regions of convex thin films are added in pairs to obtain the two magnetron components with the smallest difference between the sum of the outer region thicknesses and the sum of the inner region thicknesses, which are then selected as the optimal magnetron component combination.

[0016] Furthermore, the magnetic field strength can be adjusted by changing the number of magnetic beads or the magnetic field strength of the magnetic beads.

[0017] Furthermore, the NS spacing is adjusted by widening or narrowing the width of the yoke.

[0018] Furthermore, the peak region of the target material erosion track is adjusted by changing the position of the magnetic beads.

[0019] Furthermore, in step 2, reaction parameters are adjusted when performing thin film deposition on the wafer.

[0020] Furthermore, the reaction parameters include: power supply.

[0021] This invention also provides a magnetically controlled assembly capable of improving the uniformity of high-cavity film thickness and the filling capability, comprising a magnetic yoke, a magnetic bead fixing component, magnetic beads, a base plate, and a rotary fixing lock. The magnetic bead fixing component includes at least two inner ring through holes and at least two outer ring through holes. In one half of the magnetic bead fixing components, the outer layer of the outer ring through holes is provided with outer ring magnetic beads, and the outer layer of the inner ring through holes is provided with inner ring magnetic beads, with the number of outer ring magnetic beads being greater than the number of inner ring magnetic beads. In the other half of the magnetic bead fixing components, the inner layer of the outer ring through holes is provided with outer ring magnetic beads, and the inner layer of the inner ring through holes is provided with inner ring magnetic beads, with the number of outer ring magnetic beads being equal to the number of inner ring magnetic beads. The shape of the magnetic yoke corresponds to the distribution of the magnetic beads.

[0022] The present invention also provides a physical vapor deposition method, which uses the above-mentioned magnetron sputtering reaction with a magnetron assembly that can improve the uniformity of high cavity film thickness and the ability to fill pores.

[0023] The beneficial effects of this invention are as follows:

[0024] 1. The method of the present invention can obtain an ideal magnetron sputtering component structure. When the magnetron sputtering reaction is performed using the magnetron sputtering component, the film uniformity is high and the formation of depressions and voids in the film is effectively avoided.

[0025] 2. After removing the physical shielding, the magnetron assembly of the present invention can not only reduce the height of the wafer from the target, but also reduce the power consumed to deposit a thin film of the same thickness. Attached Figure Description

[0026] Figure 1 This diagram illustrates the deposition effect at different target heights, with the left side representing the target at a lower height and the right side representing the target at a higher height.

[0027] Figure 2 This is a schematic diagram of the area of ​​the inner and outer rings of a wafer.

[0028] Figure 3 This is a schematic diagram of atoms deposited on a wafer to form voids.

[0029] Figure 4This is a schematic diagram of a product with void defects.

[0030] Figure 5 This is a schematic diagram of the initial magnetic control assembly.

[0031] Figure 6 This is a schematic diagram of a magnetic bead fixing component.

[0032] Figure 7 This is a front view of the magnetic yoke.

[0033] Figure 8 This is a schematic diagram of the reverse side of the magnetic yoke.

[0034] Figure 9 This is a schematic diagram of the wafer measurement coordinate system.

[0035] Figure 10 This is a schematic diagram showing the distribution of different magnetic beads and the corresponding film thickness.

[0036] Figure 11 This is a schematic diagram of the final magnetic yoke.

[0037] Figure 12 This is a schematic diagram of the final magnetic control component.

[0038] Figure 13 The results of AlCu pore filling obtained in Example 2 are shown.

[0039] Figure 14 The results of AlCu pore filling obtained in the comparative example are shown.

[0040] Explanation of reference numerals in the attached figures:

[0041] 1-Sealing, 2-Void, 3-Wafer, 4-Magnetic yoke, 4-1-Outer magnetic yoke, 4-2-Inner magnetic yoke, 5-Magnetic bead fixing piece, 6-Base plate, 7-Magnetic bead, 8-Rotating fixing lock, 9-Groove, 10-Film. Detailed Implementation

[0042] The technical solutions provided by the present invention will be described in detail below with reference to specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0043] This invention designs a magnetron assembly capable of improving high-cavity film thickness uniformity and cavity filling capability. This embodiment uses an AlCu target as an example to illustrate the design method of the magnetron assembly, including the following steps:

[0044] Step 1, Set the initial arrangement of the magnetic control components

[0045] like Figure 5 , Figure 6As shown, the magnetic control component in this embodiment uses a four-ring arrangement of magnetic beads, with two rings on the innermost and two on the outermost sides. In actual installation, more or fewer rings of magnetic beads can be used as needed. The overall structure of the magnetic control component is as follows: Figure 5 As shown, from top to bottom, it includes a magnetic yoke 4, a magnetic bead fixing component 5, a base plate 6, and a rotating fixing lock 8. Magnetic beads 7 are installed inside the magnetic bead fixing component 5. The magnetic yoke 4 covers the same group of magnetic beads, used to make the group of magnetic beads form a conjugate magnetic field, such as... Figure 7 , Figure 8 As shown, in the initial state, the magnetic yoke is a common ring shape, consisting of two rings. The inner ring is the S pole, called the inner magnetic yoke 4-2, and the outer ring is the N pole, called the outer magnetic yoke 4-1. Correspondingly, the beads covering the inner magnetic yoke are called the inner ring beads, and the beads covering the outer magnetic yoke are called the outer ring beads. In this example, due to size limitations, one ring of beads covers both the inner and outer magnetic yokes. In practical applications, multiple rings of beads may also cover both the inner and outer magnetic yokes. Figure 7 The dotted line in the diagram represents the peak position of the horizontal component B of the magnetic field parallel to the target surface above the target surface under the two-ring magnetic yoke structure, which is the position of the peak radius of the target material erosion track. Preferably, the lower surface of the magnetic yoke 4 that contacts the magnetic bead 7 has a shallow groove 9 to position the magnetic bead and prevent it from moving during use. The magnetic bead holder 5 is used to install the magnetic bead 7 and has a through hole to accommodate the magnetic bead, forming a shape like... Figure 6 The arrangement shown in this example includes four through holes for the magnetic bead holder. The magnetic bead 7 is a cylindrical structure made of neodymium magnets, with a height of 32 mm and a base diameter of 17 mm. After magnetization, its N-pole magnetic field strength is 6000 Gs, with one end of the magnetic pole being N and the other S-pole along the height direction. The base plate 6, used to mount the magnetic bead 7, is magnetic. The side of the base plate 6 that contacts the magnetic bead 7 has a groove 9 for positioning the bead 7. A rotating locking latch 8 is used to fix it to the rotating mechanism, which rotates during use. The rotating locking latch 8 uses a conventional structure, and its specific composition will not be described in detail in this invention.

[0046] Step 2: Adjust parameters for deposition, measure film thickness, and classify the films.

[0047] By adjusting the parameters of the magnetron assembly, different magnetron assemblies can be obtained. Based on these magnetron assemblies, wafers are deposited. During deposition, the DC power value can be further adjusted to conduct various experiments, thereby obtaining different thin film deposition results. The thickness of the thin film 10 deposited on wafer 3 is measured to proceed to the next step of assembly and obtain the ideal magnetron assembly structure.

[0048] The resistivity of different metals is constant or varies little, and the corresponding thin film thickness can be obtained using the equation THK = ρ / Rs. ρ is the resistance (in μΩ*mm due to the real number of magnetrons); Rs is the sheet resistance (in mm). A four-probe instrument is used to test the radial sheet resistance (Rs) distribution (or film thickness) on the wafer. Since the magnetron assembly rotates during actual use, the film thickness is almost equal at points with the same radius on the wafer after deposition. Therefore, only the radial Rs or film thickness needs to be examined. Taking an 8-inch wafer as an example, the four-probe test points are established with the wafer center as the origin (0,0) and the radial direction as the x-axis, as shown below. Figure 9 The coordinate system (only the right half of the wafer is shown in the figure) has a 5mm interval between every two measurement points. The coordinates of the starting point of the test are (5,0). After removing 5mm from the edge of the wafer, 19 measurement values ​​are obtained in the radial direction of the right half of the wafer. The horizontal coordinate of the left half of the wafer is negative, with (-5,0) as the starting point of the test. After removing 5mm from the edge of the wafer, 19 measurement values ​​are obtained in the radial direction of the left half of the wafer, for a total of 38 test points. The numbering and test points are shown in Table 1 (Table 1 only lists the horizontal coordinate values ​​of the test points):

[0049] Table 1

[0050] 1 5 20 -95 2 10 21 -90 3 15 22 -85 4 20 23 -80 5 25 24 -75 6 30 25 -70 7 35 26 -65 8 40 27 -60 9 45 28 -55 10 50 29 -50 11 55 30 -45 12 60 31 -40 13 65 32 -35 14 70 33 -30 15 75 34 -25 16 80 35 -20 17 85 36 -15 18 90 37 -10 19 95 38 -5

[0051] The locations and measurement densities in the table above are for illustrative purposes only. In practical applications, the measurement locations and densities can be adjusted as needed.

[0052] After obtaining the above 38 measurements, we define the area from -50 to 50 mm on the wafer as the central region, and the areas from -95 to -55 mm and from 55 to 95 mm as the outer regions. We define M as the difference in film thickness between the outer and inner regions, in nm. M = THK average value (-95~-55 & 55~95) - THK average value (-50~50 mm),

[0053] If M>0, the film thickness result is determined to be "concave", that is, the film thickness is thin in the central region and thick in the edge region, and the corresponding magnetron control component is determined to be "concave" accordingly; if M<0, the film thickness result is determined to be "convex", that is, the film thickness is thick in the central region and thin in the edge region, and the corresponding magnetron control component is determined to be "convex".

[0054] This invention adjusts the following five key parameters: magnetic field strength, N / S spacing, magnetic bead imbalance, DC power, and the range of erosion runways on the target material.

[0055] The magnetic field strength refers to the magnetic field strength formed on the surface of the entire magnetron assembly. Controlling the magnetic field strength of a single magnetic bead controls the strength of the entire magnetic field region; the magnetic field strength of a single magnetic bead is approximately 4000-6000 Gs. In this example, the magnetic field strength on the surface of the magnetron assembly is achieved by changing the number of magnetic beads. Of course, the magnetic field strength of a single magnetic bead can also be adjusted as needed. Figure 10 In Figure A, both the inner and outer magnetic beads use half-circles, while in Figure B, both the inner and outer magnetic beads use full circles. As can be seen from the measurement diagrams of thin film 10 below Figures A and B, the film thickness results are both "convex," with Figure B showing a thicker overall film thickness.

[0056] Magnetic bead imbalance, which refers to whether the number of inner and outer magnetic beads is equal. Figure 10 In Figures B and C, the inner and outer magnetic beads are positioned the same. Figure C has more outer magnetic beads than inner ones. As shown in the thin film measurement diagrams below Figures B and C, the film thickness results are both "convex," with Figure C showing a slightly thicker overall film thickness. Similarly, in Figures D and E, the inner and outer magnetic beads are positioned the same. Figure E has more outer magnetic beads than inner ones. As shown in the thin film measurement diagrams below Figures D and E, the film thickness results are both "concave," with Figure E showing a slightly thicker overall film thickness.

[0057] The peak region of the erosion raceway on the target is the position of the line connecting the midpoints of the inner and outer magnetic yokes on the target. Since the main erosion region of the target in magnetron sputtering is the peak position of the horizontal component B of the magnetic field parallel to the target surface above the target, adjusting the peak position of this magnetic field can adjust the main sputtering region of the target. This region has the strongest electron binding ability and is the area of ​​most intense Ar ion bombardment. Based on conventional wafer sizes, this range needs to be controlled within approximately 100 mm to 125 mm. In this example, the peak position of the horizontal component of the magnetic field is adjusted by adjusting the radial distribution of the magnetic beads in the magnetron assembly. Figure 10 In Figures A, B, and C, the outer ring of magnetic beads is placed in the second ring from the outside in, and the inner ring is placed in the fourth ring from the outside in. The target erosion track is at the 100mm position, resulting in a film that is thick in the middle and thin at the edges. In Figures D and E, the outer ring of magnetic beads is placed in the first ring from the outside in, and the inner ring is placed in the third ring from the outside in. The target erosion track is at the 125mm position, resulting in a film that is thin in the middle and thick at the edges. It should be noted that... Figure 10 The ratio of the target material to the wafer differs from that of the actual product, and the wafer size is enlarged. Furthermore, the film thickness is significantly increased to better demonstrate the unevenness of the thin film.

[0058] The N-S pitch refers to the distance between the N-pole yoke (outer yoke) and the S-pole yoke (inner yoke). The main adjustment method is to increase or decrease the N-pole yoke-S-pole yoke pitch by widening the yoke width. However, it is necessary to ensure that the widths of the N-pole yoke (outer yoke) and the S-pole yoke (inner yoke) are equal. The pitch should be between 25 mm and 40 mm. Different widths will result in different uniformity.

[0059] In addition, the DC power is controlled within the range of 3.5kW to 8kW, and adjusted within this range to obtain more refined experimental results on film thickness.

[0060] Step 3: Based on the experimental data from Step 2, analyze the characteristics of the combined magnetic control components.

[0061] Based on the film thickness data obtained using different parameters in step 2, integrating multiple target erosion tracks can yield an ideal magnetic yoke shape. In this embodiment, two target erosion tracks are integrated. The film thickness measurement and determination method in step 2 categorizes the film thickness results and magnetron splicing components into two main types: "concave" and "convex." When finally determining the characteristics of the magnetron splicing components (bead arrangement, N / S pole spacing, or magnetic field lines), it is necessary to combine the characteristics of these two types of magnetron splicing components. Based on the film thickness data from each experiment in step 2, the average film thickness M in the outer region of each experiment is obtained. 外i (THK average value (-95~-55 & 55~95)) and the average film thickness M in the inner region 内i (THK average value (-50~50 mm)), i is the experimental number. For each type of concave film M... 外i and M 内i With various "convex" type thin films M 外i and M 内i The sums of the outer and inner region film thicknesses of each thin film combination are obtained by adding them pairwise. The magnetron splice corresponding to the two thin film results with the smallest difference between the sums of the outer and inner region film thicknesses are selected. Since the magnetron splice is rotating, half of the magnetron splice can be selected when using its characteristics, and half of the magnetic beads are combined. Specifically, using... Figure 10 For example, the thin films obtained by magnetron splicing components A, B, and C are all "convex," while the thin films obtained by magnetron splicing components D and E are all "concave." Calculate the average thickness M of the outer region of each thin film. 外i and the average film thickness M in the inner ring region 内i Combining convex and concave thin films yields six combinations: AD, AE, BD, BE, CD, and CE. Taking the AD combination as an example, thin film A is combined with film M... 外A M 内A respectively with D thin film M 外D M内D Add them together to get M. 外总 =(M 外A +M 外D M 内总 =(M 内A +M 内D ), calculate |M 外总- M 内总 | is the difference between the sum of the film thicknesses in the outer region and the sum of the film thicknesses in the inner region. This yields |M| for each combination. 外总- M 内总 The combination with the smallest difference is taken as the ideal combination with the best uniformity. Figure 10 In the diagram, the film thickness distribution obtained from B is "convex," and the film thickness distribution obtained from E is "concave." The uniformity of the film thickness in their outer and inner regions is optimal when combined. Therefore, taking half of the magnetic bead distribution from B and half of the magnetic bead distribution from E, the combined magnetic bead distribution is as follows. Figure 10 As shown in F.

[0062] When assembling, it is preferable to use "convex" type magnetron assembly with different numbers of inner and outer magnetic beads. The "convex" type magnetron assembly with unbalanced inner and outer magnetic beads will deposit a thin film with less thickness in the central region, making it easier to assemble a magnetic bead distribution with a thicker film thickness in the central region.

[0063] When the film thickness distribution uniformity meets the requirement of <3%, feature combination is not required. For example, if the table shows 38 measurement points, and the average of 20 points minus the average of the other 18 points is less than 3%, then the requirement is met. The magnitude of |M| (absolute value) determines the "unevenness" of the film thickness distribution. We use the coefficient of variation (CV) to study the relationship between |M| and uniformity. The CV is the ratio of the standard deviation to the mean, and it is required that CV < 0.03. We assume the most stringent case: taking the 38 measurements in Table 1 as an example, when the data measured in the outer and inner circles are completely identical (i.e., the 20 numbers in the inner circle are all equal to their average 'a', and the 18 numbers in the outer circle are all equal to their average 'b'), the total variance is minimized, and the CV is also minimized. If the CV is less than 0.03 in this case, then any case with differences within a group (with a larger total variance) necessarily meets the condition.

[0064] Let the difference between the two sets of averages be d = a − b, and the overall average of the 38 numbers be μ.

[0065] Overall average: μ= Total variance: When there are no differences within groups, the total variance is determined only by the differences between groups: σ 2 = Substitute and Simplifying, we get: σ 2 = d2 , σ= ≈0.498d.

[0066] Coefficient of variation inequality: CV = = <0.03.

[0067] Solving this inequality, we get: d < ≈ 0.0601μ.

[0068] That is, when |M| < 0.0601μ, the requirement of film thickness distribution uniformity of <3% must be met. μ is the average of all 38 measurements. Only when |M| > 0.0601μ are the "uneven" characteristics of the magnetron sputtering components suitable for combination. To improve the utilization rate of the target material, a combination of multiple magnetic lines is recommended in practical applications.

[0069] In this example, we combined the peak radii (range of 100mm~125mm) of two target erosion tracks, according to... Figure 10 The distribution of magnetic beads in F was obtained Figure 11 The magnetic yoke shown yields a thin film with superior uniformity. The final determined magnetron assembly is as follows: Figure 12 As shown, the peak radius of the target erosion track formed is 100mm in some areas and 125mm in others. The magnetron sputtering assembly has four rings of magnetic beads. We call the two rings furthest from the center the outer rings, and the two rings closest to the center the inner rings. The magnetic beads furthest from the center are called the outer layer, and the beads closest to the center are called the inner layer. Figure 10 Taking F as an example, the distribution of magnetic beads in the magnetic control assembly is explained. In the upper half of the magnetic control assembly, the outer ring of magnetic beads is located on the outer layer and is evenly distributed, while the inner ring of magnetic beads is also located on the outer layer and is evenly distributed. The number of outer ring magnetic beads is greater than the number of inner ring outer ring magnetic beads. In the lower half of the magnetic control assembly, the outer ring of magnetic beads is located on the inner layer and is evenly distributed, while the inner ring of magnetic beads is also located on the inner layer and is evenly distributed. The number of outer ring inner ring magnetic beads is equal to the number of inner ring inner ring magnetic beads. The shape of the yoke corresponds to the distribution of magnetic beads; that is, part of the outer yoke covers the outer ring outer ring magnetic beads, and another part covers the outer ring inner ring magnetic beads. Similarly, part of the inner yoke covers the inner ring outer ring magnetic beads, and another part covers the inner ring inner ring magnetic beads.

[0070] The method of this invention can also be applied to other metal targets. By collecting basic data on target sputtering through the initial magnetic beads and the corresponding metal target erosion runway distribution, a suitable magnetic bead distribution and final magnetic yoke shape can be obtained after combination.

[0071] The following examples further illustrate the application effects of the magnetron sputtering component designed in this invention. Example 1 involves planar film deposition on a patternless wafer, primarily testing the sheet resistance of the thin film. Example 2 involves planar film deposition on a patterned wafer, primarily testing the AlCu via-filling capability of the magnetron sputtering component of this invention.

[0072] Example 1: Magnetron sputtering reaction was performed using the magnetron assembly of this invention on the SJI-SEMI Depomerits P188 Pro PVD platform. The target material was AlCu with a purity of 99.999%, a diameter of 320–322 mm, and a distance of 150 mm (130–200 mm) between the target and the wafer. The wafer was a SiO2 substrate obtained by furnace tube CVD process. First, the wafer was transferred to the magnetron sputtering vacuum chamber, where the vacuum level was maintained at 5.0 × 10⁻⁶. -8 Below Torr. Then, Ar gas was introduced at a flow rate of 35 sccm, the chamber reaction pressure was 2.1 mTorr, and the stage temperature was 400℃. The target input power was set to 8000W, and the sputtering time was 100s. The film thickness, sheet resistance, and other data were measured using a 49-point measurement method (the wafer is divided into three rings, with one measurement point at the center, 12 measurement points in the first ring (inner ring), 16 measurement points in the second ring (middle ring), and 20 measurement points in the third ring (outer ring), for a total of 49 measurement points). The average thickness and average sheet resistance were calculated, and the film uniformity was calculated based on the thickness values ​​of the 49 measurement points. Table 2 shows the film data obtained from the magnetron sputtering assembly.

[0073] Table 2

[0074]

[0075] As shown in Table 2, the uniformity of the thin film obtained by using the magnetron assembly can be controlled within 2% without sacrificing the deposition rate.

[0076] Example 2: Magnetron sputtering reaction was performed using the magnetron assembly of this invention on the SJI-SEMI Depomerits P188 Pro PVD platform. The target material was AlCu with a purity of 99.999%, a diameter of 320–322 mm, and a distance of 150 mm (130–200 mm) between the target and the wafer. The wafer was a SiO2 substrate obtained by furnace tube CVD. First, the wafer was transferred to the magnetron sputtering vacuum chamber, and the chamber vacuum was maintained below 5.0 × 10⁻⁸ Torr. Then, Ar gas was introduced at a flow rate of 30 sccm, the chamber reaction pressure was 2.1 mTorr, and the stage temperature was 400 °C. The target input power was set to 8000 W, and the sputtering time was 20 min.

[0077] like Figure 13 As shown, no depressions or voids were observed in AlCu within the patterns (mainly grooves) on the wafer, and no defects were found in the filling of the holes at any location.

[0078] Comparative Example: Based on the SJI-SEMI Depomerits P188 Pro PVD platform, using the older magnetron sputtering assembly. AlCu with a target purity of 99.999% was selected, with a target diameter of 320–322 mm and a target-wafer distance of 150 mm. The wafer was a SiO2 substrate obtained through furnace tube CVD. First, the wafer was transferred to the magnetron sputtering vacuum chamber, maintaining a vacuum level below 5.0 × 10⁻⁸ Torr. Then, Ar gas was introduced at a flow rate of 35 sccm, the chamber reaction pressure was 2.1 mTorr, the back argon flow rate of the wafer was 15 sccm, and the stage temperature was 400℃. The target input power was set to 8000 W, and the sputtering time was 20 min.

[0079] like Figure 14 As shown, AlCu exhibits depressions and voids in the patterns (mainly grooves) on the wafer.

[0080] Table 3 shows the differences between the magnetron assembly of the present invention and the comparative example. The assembly of the present invention after removing the physical shield not only reduces the height from the wafer to the target, but also reduces the number of kWh required to deposit the same thickness of film (the old version required a physical shield (placed between the target and the wafer to shield the film in the middle area and reduce the thickness of the film deposited in the middle), and a certain number of films were deposited on the shield, causing losses), and ensured that the uniformity was within 3%.

[0081] Table 3

[0082]

[0083] It should be noted that the above content merely illustrates the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. For those skilled in the art, various improvements and modifications can be made without departing from the principle of the present invention, and all such improvements and modifications fall within the scope of protection of the claims of the present invention.

Claims

1. A design method for a magnetron assembly capable of improving high-cavity film thickness uniformity and orifice filling capability, characterized in that, Includes the following steps: Step 1: Set the initial arrangement of the magnetic control components. The magnetic control components include a magnetic yoke, a magnetic bead fixing component, a magnetic bead, a base plate, and a rotating fixing lock. The magnetic bead fixing component has at least four through holes for accommodating the magnetic bead. Step 2: Adjust the magnetron assembly parameters and deposit film on the wafer based on the magnetron assembly with different parameters to obtain the film thickness deposited on the wafer surface; the magnetron assembly parameters include one or more of the following parameters: magnetic field strength, N / S spacing, imbalance between inner and outer magnetic beads, and peak area of ​​the target erosion track; Based on the film thickness results, the thin film and the magnetron assembly used in the deposition process are divided into two categories: concave and convex. Specifically, this involves obtaining the difference M between the average film thickness of the outer region and the average film thickness of the inner region of the thin film on the wafer. If M > 0, the film thickness result is determined to be concave, and the corresponding magnetron assembly is determined to be concave. If M < 0, the film thickness result is determined to be convex, and the corresponding magnetron assembly is determined to be convex. Step 3: Based on the thin film thickness results obtained in Step 2, combine the concave and convex magnetron components to obtain the magnetron component combination with the best film thickness uniformity. Combine the half of the magnetic bead distribution of the concave magnetron component and the half of the magnetic bead distribution of the convex magnetron component in the best magnetron component combination to obtain the final magnetic bead distribution and the magnetic yoke shape corresponding to the magnetic bead distribution.

2. The design method of the magnetron assembly capable of improving high-cavity film thickness uniformity and orifice filling capability according to claim 1, characterized in that, In step 3, based on the thin film thickness results obtained in step 2, the combination of concave and convex magnetron components yields a magnetron component combination with optimal film thickness uniformity, including: The average thicknesses of the inner and outer regions of concave thin films and the average thicknesses of the inner and outer regions of convex thin films are added in pairs to obtain the two magnetron components with the smallest difference between the sum of the outer and inner region thicknesses, which are then selected as the optimal magnetron component combination.

3. The design method of the magnetron assembly capable of improving high-cavity film thickness uniformity and orifice filling capability according to claim 1, characterized in that, The magnetic field strength is adjusted by changing the number of magnetic beads or the magnetic field strength of the magnetic beads.

4. The design method of the magnetron assembly capable of improving high-cavity film thickness uniformity and orifice filling capability according to claim 1, characterized in that, The NS spacing is adjusted by widening or narrowing the width of the yoke.

5. The design method of the magnetron assembly capable of improving high-cavity film thickness uniformity and orifice filling capability according to claim 1, characterized in that, The peak region of the target erosion track is adjusted by changing the position of the magnetic beads.

6. The design method of the magnetron assembly capable of improving high-cavity film thickness uniformity and orifice filling capability according to claim 1, characterized in that, In step 2, reaction parameters are also adjusted during wafer deposition.

7. The design method of the magnetron assembly capable of improving high-cavity film thickness uniformity and orifice filling capability according to claim 6, characterized in that, The reaction parameters include: power supply.

8. A magnetic control assembly capable of improving high-cavity film thickness uniformity and cavity filling capability, comprising a magnetic yoke, a magnetic bead holder, a magnetic bead, a base plate, and a rotary fixing lock, wherein the magnetic bead holder comprises at least two inner ring through holes and at least two outer ring through holes, characterized in that, The magnetic control assembly is designed using the design method of any one of claims 1-7, which can improve the uniformity of high cavity film thickness and the ability to fill pores. In one half of the magnetic bead fixing components, the outer layer of the outer ring through hole is provided with outer ring magnetic beads, and the outer layer of the inner ring through hole is provided with inner ring magnetic beads, with the number of outer ring magnetic beads being greater than the number of inner ring magnetic beads. In the other half of the magnetic bead fixing components, the inner layer of the outer ring through hole is provided with outer ring magnetic beads, and the inner layer of the inner ring through hole is provided with inner ring magnetic beads, with the number of outer ring magnetic beads being equal to the number of inner ring magnetic beads. The shape of the magnetic yoke corresponds to the distribution of the magnetic beads.

9. A physical vapor deposition method, using the magnetron sputtering reaction described in claim 8, which can improve the uniformity of high cavity film thickness and the ability to fill pores.

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