Sputtering device

Abstract

This invention relates to a sputtering apparatus for reducing the frequency of replacing a shielding member. The sputtering apparatus includes: a target material that disperses sputtered particles toward a substrate; and a shielding member located between the substrate and the target material, which limits the dispersion range of sputtered particles relative to the substrate during film formation, wherein the shielding member is a rotating body having an outer peripheral surface, and by rotating the rotating body, the region of the outer peripheral surface facing the target material is changed.

Description

Technical Field

[0001] This invention relates to a sputtering apparatus. Background Technology

[0002] In the manufacture of organic EL displays and the like, there is a known technique for forming a film on a substrate using a sputtering apparatus. Among such sputtering apparatuses, there are those with a shielding member disposed between the target and the substrate (e.g., Patent Document 1). By limiting the dispersion range of sputtered particles flying from the target using the shielding member, it is possible to achieve uniform film thickness and reduce damage to the substrate's base layer.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2019-090083 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] Sputtered particles accumulate on the shielding member due to repeated film-forming processes. This accumulation forms a film on the surface of the shielding member. Depending on the film thickness, the dimensions of the shielding member change, and the range of dispersion limits also change. This contributes to a decrease in film-forming accuracy. Shielding members with thickened films need to be replaced, but this requires temporary manufacturing interruptions, and frequent replacements reduce productivity.

[0008] This invention provides a technique to reduce the frequency of replacing shielding components.

[0009] Methods for solving problems

[0010] According to the present invention, a sputtering apparatus is provided, comprising:

[0011] The target material, which sputters particles toward the substrate; and

[0012] A shielding member, located between the substrate and the target, limits the dispersion range of sputtered particles relative to the substrate during film formation.

[0013] in,

[0014] The shielding component is a rotating body with an outer peripheral surface.

[0015] By rotating the rotating body, the region on the outer peripheral surface facing the target material is changed.

[0016] The effects of the invention

[0017] According to the present invention, a technique can be provided to reduce the frequency of replacement of shielding components. Attached Figure Description

[0018] Figure 1 (A) and (B) are schematic diagrams of a sputtering apparatus according to an embodiment of the present invention.

[0019] Figure 2 (A) is an illustration of the film-forming action, and (B) is a diagram showing other rotational control examples of the shielding member.

[0020] Figure 3 (A) is a diagram showing an example of a rotating mechanism for a target and a shielding member, and (B) is a diagram showing other examples of shapes for the shielding member.

[0021] Figure 4 (A) is a diagram showing another layout example of the target and shielding member, and (B) is a diagram showing another example of the relative movement of the substrate with respect to the target and shielding member.

[0022] Figure 5 This is a diagram showing other examples of target materials and magnet units.

[0023] Explanation of reference numerals in the attached figures

[0024] 1 sputtering apparatus, 6 targets, 12 shielding components, 100 substrates. Detailed Implementation

[0025] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Furthermore, the following embodiments do not limit the invention as defined in the claims. Although multiple features are described in the embodiments, not all of these features are necessarily essential to the invention, and multiple features can be arbitrarily combined. In the accompanying drawings, the same or identical structures are labeled with the same reference numerals, and repeated descriptions are omitted.

[0026] <First Implementation>

[0027] <Structure of the sputtering device>

[0028] Figure 1 (A) and (B) are schematic diagrams of a sputtering apparatus 1 according to an embodiment of the present invention. Figure 1 (A) is a diagram showing the sputtering device 1 as viewed from the side. Figure 1 (B) is a diagram showing the sputtering device 1 as viewed from above. In each diagram, arrow Z indicates the vertical direction (direction of gravity), and arrows X and Y indicate mutually orthogonal horizontal directions.

[0029] The sputtering apparatus 1 is a film-forming apparatus for forming a film on a substrate 100. It can be used, for example, in manufacturing apparatuses for electronic devices or optical components such as display devices (flat panel displays, etc.), thin-film solar cells, and organic photoelectric conversion elements (organic thin-film imaging elements), and particularly in manufacturing apparatuses for organic EL panels. In the case of manufacturing organic EL panels, for example, an organic film is pre-formed on the lower surface of the substrate 100, and the sputtering apparatus 1 forms an electrode film on the organic film by sputtering.

[0030] The sputtering apparatus 1 has a box-shaped vacuum chamber 2. The vacuum chamber 2 is connected to a vacuum pump (not shown), which can depressurize the internal space by exhausting gas from the vacuum pump. Inert gases such as argon are supplied to the internal space of the vacuum chamber 2 through a gas supply unit 3.

[0031] The sputtering apparatus 1 includes a moving unit 4 for transporting a substrate within a vacuum chamber 2. The moving unit 4 includes a pair of guide rails 4a and a carrier 5 supported on and moving along the guide rails 4a. Each guide rail 4a extends in the X direction, and the pair of guide rails 4a are separated in the Y direction. The moving unit 4 has a drive mechanism such as a linear motor or a ball screw mechanism, which drives the carrier 5 along the pair of guide rails 4a. Figure 1 In (B), the solid and dashed lines indicate the reciprocating motion in the X direction.

[0032] The carrier 5 has a holding portion 5a for holding the substrate 100. The substrate 100 is conveyed into the vacuum chamber 2 through the inlet gate 2a and held on the carrier 5. The substrate 100 is moved horizontally in the X direction within the vacuum chamber 2 by the movement of the carrier 5. During the movement, sputtered particles from the target material 6 accumulate on the lower surface of the substrate 100, forming a film. The substrate 100 after film formation is discharged out of the vacuum chamber 2 through the outlet gate 2b.

[0033] In this embodiment, the target 6 is a rotating target that can rotate freely about the rotation center line C1 in the Y direction. The target 6 is supported on a pair of support platforms 10. A motor 11 is provided on one of the support platforms 10, and the target 6 rotates by the driving force of the motor 11 as the driving source.

[0034] The target material 6 has a cylindrical shape, and a cathode electrode 7 is provided on its inner circumferential surface. It is maintained at a cathode potential and discharged by applying voltage through a voltage application unit 8. In addition, the sputtering apparatus 1 of this embodiment is a magnetron sputtering apparatus, and a magnet 9 that forms a magnetic field on the surface of the target material 6 is arranged in the upper part of the internal space of the target material 6.

[0035] Magnet 9 includes a central magnet 9a extending in the Y direction, peripheral magnets 9b surrounding the central magnet 9a, and a yoke 9c. The peripheral magnet 9b is a ring-shaped magnet having a pair of straight sections extending parallel to the central magnet 9a in the Y direction and a connecting portion connecting the two ends of the pair of straight sections in the Y direction. Figure 1 The diagram in (A) shows a cross-section of a pair of straight sections of the peripheral magnet 9b.

[0036] The central magnet 9a and the peripheral magnets 9b have opposite polarities, and the magnetization direction of the central magnet 9a is the direction of the central reference line N0. The central reference line N0 is a straight line that passes through the central portion of the magnetic pole of the central magnet 9a in the X direction and extends in a direction orthogonal to the surface of the target material 6 (radial direction of the target material 6). In this embodiment, the central reference line N0 is a line that extends in the Z direction and passes through the rotation center line C1 of the target material 6, and is orthogonal to the transport surface of the substrate 100. The magnetization direction of the peripheral magnets 9b extends parallel to that of the central magnet 9a, and the inner ends of the central magnet 9a and the peripheral magnets 9b are connected by a yoke 9c. As a result, the magnetic field near the surface of the target material 6 has magnetic field lines that loop back from the magnetic pole of the central magnet 9a toward the peripheral magnets 9b. Electrons are captured by this magnetic field, and the plasma is concentrated near the surface of the target material 6, thereby improving the sputtering efficiency.

[0037] The shielding member 12 is an anti-adhesion member located between the substrate 100 and the target 6, which structurally limits the scattering range of sputtered particles relative to the substrate 100 during film formation. The shielding member 12 is a rotating body having an outer peripheral surface for sputtered particles to adhere to and rotating freely about a rotation center line C2 in the Y direction. The shielding member 12 is supported on a pair of support platforms 10 directly above the target 6. A central reference line N0 passes through the shielding member 12, particularly through the rotation center line C2. A motor 14 is provided on one of the support platforms 10, and the shielding member 12 rotates independently of the target 6 by the driving force of the motor 14.

[0038] In this embodiment, the shielding member 12 has a cylindrical shape, and an anode electrode 13 is provided on its inner circumferential surface, which has the effect of stabilizing the plasma. Stabilizing the plasma, which affects the film formation rate, can reduce the film thickness deviation between substrates and improve the yield. The anode electrode 13 is maintained at the anode potential (ground potential, the same potential as the wall of the vacuum chamber 2).

[0039] The sputtering apparatus 1 includes a cooling unit 15 for cooling the shielding member 12. The cooling unit 15 has a circulation unit 15a disposed outside the vacuum chamber 2 and a piping 15b extending from the wall of the vacuum chamber 2 and a support platform 10 on the other side toward the shielding member 12. The piping 15b is a U-shaped pipe extending from one end in the Y direction to the other end inside the shielding member 12 and then turning back to extend from the other end to one end. The circulation unit 15a includes a pump that circulates a cooling medium such as water between the circulation unit 15a and the piping 15b, and a heat exchanger that maintains the temperature of the cooling medium at a constant temperature by performing heat exchange on the circulating cooling medium. By cooling the shielding member 12, sputtered particles adhering to the shielding member 12 can be prevented from flying toward the substrate 100.

[0040] Furthermore, in this embodiment, the shielding member 12 is cooled via piping 15b. However, it is also possible to directly supply a cooling medium such as water into the interior of the shielding member 12, filling the interior of the shielding member 12 with the cooling medium to cool it. In this case, the shielding member 12 is insulated from the anode electrode 13 and sealed to prevent leakage of the cooling medium.

[0041] The sputtering apparatus 1 includes a control unit 16. The control unit 16 includes at least one processor, at least one storage device, and an interface for inputting and outputting data to sensors and actuators, and controls the sputtering apparatus 1. The storage device is, for example, a memory such as RAM or ROM. The processor executes programs stored in the storage device to perform drive control of motors 11 and 14 and the moving unit 4, etc.

[0042] <Film Formation Process>

[0043] Reference Figure 2 (A) describes the film formation operation of the sputtering apparatus 1. While the substrate 100 is continuously moved by the moving unit 4, sputtering particles P are scattered from the target material 6 onto the substrate 100 and accumulate on the lower surface of the substrate 100 to form a film. Figure 2 In diagram (A), the elliptical circle L near the surface of the target 6 schematically represents the region of plasma concentration. It is known that the plasma density is high at the location where the magnetic flux density component in the normal direction of the target 6 surface is zero, resulting in concentrated sputtering of particles. This point is located between the straight sections of the central magnet 9a and the peripheral magnets 9b. Assuming that the sputtered particles emitted from the target 6 accumulate on the transport surface, the distribution of the deposition rate per unit time becomes a mountain-shaped distribution with a peak near the central reference line N0, decreasing in rate upstream and downstream in the X direction.

[0044] In this embodiment, the shielding member 12 is located on the central reference line N0, therefore, the scattering range of sputtered particles P is limited near the central reference line N0. Thus, the scattering range becomes the range on both sides of the shielding member 12 in the X direction where the film formation rate is relatively low. Sputtered particles scattered in the range on both sides of the shielding member 12 in the X direction tend to scatter in the D1 or D2 direction, which is inclined relative to the normal direction (Z direction) of the substrate 100. In such cases... Figure 2 When the lower surface of the substrate 100, which serves as the film-forming surface, is uneven as illustrated in (A), sputtered particles that fly in the D1 or D2 direction tend to accumulate on the uneven side surface, thereby improving the side coverage.

[0045] During film formation, drive motors 11 and 14, the target material 6, and the shielding member 12 rotate continuously (rotate) in the direction of arrows R1 and R2 (clockwise). As described above, near the central reference line N0, the film formation rate is high, resulting in a large accumulation of sputtered particles relative to the shielding member 12. Typically, in such a structure, the shielding member has a short lifespan and requires frequent replacement. This is because as the film thickness increases, the dimensions of the shielding member, including the film, change, causing variations in the scattering range, or the film becomes more prone to peeling off and adhering to the surface of the target material 6, potentially contributing to particle generation.

[0046] However, in this embodiment, the shielding member 12 rotates, thereby cyclically changing the area facing the target material 6 (in this embodiment, the area is approximately 60 degrees (total 120 degrees) on both sides of the central reference line N0 in the X direction). Since the deposition area of ​​sputtered particles on the shielding member 12 can be increased, the increase in film thickness can be delayed. That is, the frequency of replacing the shielding member 12 can be reduced. By continuously rotating the shielding member 12, localized increases in film thickness can also be prevented, thus extending the lifespan of the shielding member 12.

[0047] <Second Implementation>

[0048] In the first embodiment, the shielding member 12 is rotated continuously during the film formation process, but it can also be stopped during the film formation process and rotated when predetermined rotation conditions are met. In other words, it can also be rotated intermittently. Rotation conditions include, for example, rotating according to each substrate, rotating according to multiple substrates, rotating according to a predetermined time, or rotating according to the operator's instructions. Figure 2(B) is an explanatory diagram. In the illustrated example, as shown in state ST1, film formation on the substrate 100 is performed with the rotation of the shielding member 12 stopped. Sputtered particles are deposited locally (at the bottom) on the outer peripheral surface of the shielding member 12 to form a film. When the rotation condition is met, as shown in state ST2, the shielding member 12 is rotated. The amount of rotation is, for example, the amount by which the area facing the target material 6 is replaced (120 degrees in the structure of the first embodiment).

[0049] By intermittently rotating the shielding member 12 in this way, the frequency of replacement of the shielding member 12 can also be reduced.

[0050] Alternatively, the rotation of the shielding member 12 can be performed manually without automation via the motor 14. In the case of manual operation, for example, the rotation axis of the shielding member 12 can be extended outward through the side wall of the vacuum chamber 2, allowing the operator to manually rotate the rotation axis.

[0051] <Third Implementation Method>

[0052] In the first embodiment, motors 11 and 14 are respectively provided on the target material 6 and the shielding member 12 as driving sources, but they can also share a single motor to rotate the target material 6 and the shielding member 12. Figure 3 (A) indicates that the institution is an example.

[0053] A gear 18 is provided on the output shaft of the shared motor 17. Gears 19 and 20 are respectively provided on the rotation center shaft of the target 6 and the shielding member 12, and these gears 19 and 20 mesh with gear 18. By driving the motor 17, the target 6 and the shielding member 12 can be rotated simultaneously. The rotational speed ratio of the target 6 and the shielding member 12 can also be adjusted according to the gear ratio of gears 18 to 20.

[0054] Figure 3 The example in (A) uses a gear mechanism as the mechanism for transmitting driving force from the common motor 17 to the target 6 and the shielding member 12, but it can also be other mechanisms such as belt drive.

[0055] <Fourth Implementation>

[0056] In the first embodiment, a cylindrical shielding member 12 is shown, but the shielding member 12 may also be a square tube shape. Figure 3(B) represents one example. In the illustrated example, the shielding member 12 has a rectangular shape with a regular pentagonal cross-section, and its outer peripheral surface is composed of five planes. As shown in the illustrated example, one of the five planes is aligned with the target material 6 to deposit a film on the substrate 100. By rotating the shielding member 12 by 72 degrees, another plane can be aligned with the target material 6. In this embodiment, by intermittently rotating the shielding member 12 as described in the second embodiment, the uniformity of the scattering range of the sputtered particles P can be maintained while the five planes of the shielding member 12 are utilized effectively in sequence.

[0057] <Fifth Implementation>

[0058] In the first embodiment, the target 6 and the shielding member 12 are arranged vertically, but other arrangements are also possible. Figure 4 (A) represents one example. In the illustrated example, the shielding member 12 is positioned offset from the target 6 directly above it in the X direction. Furthermore, the magnet 9 is configured such that its central reference line N0 slopes upstream from the Z direction in the transport direction of the substrate 100. The shielding member 12 limits the scattering range of sputtered particles P in regions with lower film deposition rates. The substrate 100 is positioned on the central reference line N0, where film deposition rates are high, immediately after entering the scattering range of sputtered particles P, enabling the deposition of a thicker film from the initial stage of film deposition.

[0059] In addition, Figure 4 In example (A), the piping 15b is arranged vertically. By making the lower piping 15b the supply side of the cooling medium and the upper piping 15b the discharge side of the cooling medium, the cooling performance of the target material 6 side of the shielding member 12 can be improved.

[0060] <Sixth Implementation Method>

[0061] In the first embodiment, a moving unit 4 is exemplified as a unit that moves the substrate 100 relative to the shielding member 12 and the target 6 during film formation. However, the shielding member 12 and the target 6 can also be moved. Figure 4 (B) represents one example.

[0062] The illustrated moving unit 21 includes a guide rail 22 extending in the X direction and a slider 23 guided by the guide rail 22 and capable of moving in the X direction. A pair of support platforms 10 are mounted on the slider 23. The moving unit 21 has a drive mechanism such as a linear motor or ball screw mechanism, which drives the slider 23 to reciprocate along the pair of guide rails 22 between the solid line position and the dashed line position in the X direction. The substrate 100 is stationary during the film deposition process. While the slider 23 moves, sputtered particles are emitted from the target material 6 to deposit a film on the substrate 100.

[0063] exist Figure 4 In example (B), the piping 15b is also arranged vertically. By making the lower piping 15b the supply side of the cooling medium and the upper piping 15b the discharge side of the cooling medium, the cooling performance of the target material 6 side of the shielding member 12 can be improved.

[0064] <Seventh Implementation>

[0065] In the first embodiment, a rotating target 6 is exemplified as the target 6, but a flat target can also be used. Figure 5 This is one example. In the illustrated example, a flat target 25 is used instead of a rotating target 6. The structure of the magnet 9 is basically the same as in the first embodiment. Figure 5 In this example, the piping 15b is also arranged vertically. By making the lower piping 15b the supply side of the cooling medium and the upper piping 15b the discharge side of the cooling medium, the cooling performance of the target material 25 side of the shielding member 12 can be improved.

[0066] In addition, in the first embodiment, a structure is shown in which sputtered particles are emitted to a substrate above the target, but it is also possible to have a structure in which sputtered particles are emitted to a substrate below the target.

[0067] <Other Implementation Methods>

[0068] The present invention can also be implemented by supplying a program that implements one or more functions of the above-described embodiments to a system or device via a network or storage medium, and having the program read and executed by one or more processors in the computer of the system or device. Alternatively, it can be implemented by a circuit (e.g., an ASIC) that implements one or more functions.

[0069] The invention is not limited to the embodiments described above, and various changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, the claims are appended to disclose the scope of the invention.

Claims

1. A sputtering apparatus, the sputtering apparatus comprising: The target material, which sputters particles toward the substrate; and A shielding member, located between the substrate and the target, limits the dispersion range of sputtered particles relative to the substrate during film formation. Its features are, The shielding component is a rotating body with an outer peripheral surface. By rotating the shielding member, the area on the outer peripheral surface facing the target material is changed. The sputtering apparatus includes: A driving source, the output of which is a driving force that causes the shielding member to rotate; and Control unit, which controls the drive source, The target material is a rotating target material. The driving source is a shared driving source that causes the shielding member and the target material to rotate simultaneously. The shielding member is a cylindrical rotating body that rotates continuously around a rotation center line during the film formation process.

2. The sputtering apparatus according to claim 1, characterized in that, The sputtering apparatus also includes a cooling component for cooling the shielding member.

3. The sputtering apparatus according to claim 1, characterized in that, The sputtering device is a magnetron sputtering device. The shielding member is maintained at an anode potential, and the target material is maintained at a cathode potential.

4. The sputtering apparatus according to claim 1, characterized in that, The sputtering apparatus includes a moving component that moves the substrate relative to the shielding member and the target material during film formation.

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