JP2023091409A - Sputtering device - Google Patents

Abstract

To reduce frequency of reducing a shield member.SOLUTION: A sputtering device includes: a target for scattering sputtering particles to a substrate; and a shield member positioned between the substrate and the target and regulating a scattering range of sputtering particles with respect to the substrate at the time of depositing a film. The shield member is a rotating body with an outer peripheral surface, where the rotation of the rotating body changes a region opposite to the target of the outer peripheral surface.SELECTED DRAWING: Figure 2

Description

The present invention relates to a sputtering apparatus.

2. Description of the Related Art A technique of forming a film on a substrate using a sputtering device is known in the manufacture of organic EL displays and the like. As such a sputtering apparatus, a sputtering apparatus provided with a shielding member between a target and a substrate is known (for example, Patent Document 1). By controlling the scattering range of the sputtered particles scattered from the target by the shielding member, it is possible to make the film thickness uniform and reduce damage to the underlying layer of the substrate.

JP 2019-090083 A

Sputtered particles are deposited on the shielding member by repeating the film formation process. A film is formed on the surface of the shielding member by deposition of the sputtered particles. The dimensions of the shielding member change according to the film thickness, and the scattering control range changes. This causes a decrease in film formation accuracy. A thick shielding member needs to be replaced, but it is necessary to temporarily suspend production for replacement, and frequent replacement lowers productivity.

The present invention provides a technique for reducing the replacement frequency of shielding members.

According to the invention,
a target for scattering sputtered particles onto the substrate;
a shielding member positioned between the substrate and the target for controlling a scattering range of sputtered particles with respect to the substrate during film formation;
A sputtering apparatus comprising
The shielding member is a rotating body having an outer peripheral surface,
A region of the outer peripheral surface facing the target is changed by the rotation of the rotating body.
There is provided a sputtering apparatus characterized by:

ADVANTAGE OF THE INVENTION According to this invention, the technique which reduces the exchange frequency of a shielding member can be provided.

(A) and (B) are schematic diagrams of a sputtering apparatus according to an embodiment of the present invention. (A) is an explanatory diagram of the film formation operation, and (B) is a diagram showing another example of rotation control of the shielding member. (A) is a diagram showing an example of a rotation mechanism of a target and a shielding member, and (B) is a diagram showing another shape example of the shielding member. (A) is a diagram showing another layout example of the target and the shielding member, and (B) is a diagram showing another example of relative movement between the substrate and the target and the shielding member. The figure which shows the other example of a target and a magnet unit.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. In addition, the following embodiments do not limit the invention according to the scope of claims. Although multiple features are described in the embodiments, not all of these multiple features are essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant description is omitted.

<First Embodiment>
<Structure of sputtering device>
1(A) and 1(B) are schematic diagrams of a sputtering apparatus 1 according to an embodiment of the present invention. FIG. 1(A) is a side view of the sputtering apparatus 1, and FIG. ) is a top view of the sputtering apparatus 1. FIG. In each figure, arrow Z indicates the vertical direction (direction of gravity), and arrow X and arrow Y indicate horizontal directions perpendicular to each other.

The sputtering apparatus 1 is a film-forming apparatus that forms a film on the substrate 100, and includes electronic devices such as display devices (flat panel displays, etc.), thin-film solar cells, organic photoelectric conversion elements (organic thin-film imaging elements), and the like. The present invention can be applied to a manufacturing apparatus for manufacturing optical members and the like, and particularly applicable to a manufacturing apparatus for manufacturing an organic EL panel. When applied to manufacture of an organic EL panel, for example, an organic film is formed in advance on the lower surface of the substrate 100, and the sputtering device 1 forms an electrode film on the organic film by sputtering.

A sputtering apparatus 1 has a box-shaped vacuum chamber 2 . The vacuum chamber 2 is connected to a vacuum pump (not shown), and the internal space can be evacuated by evacuation by the vacuum pump. An inert gas such as argon is supplied to the internal space of the vacuum chamber 2 by a gas supply unit 3 .

The sputtering apparatus 1 comprises a moving unit 4 that transports the substrate within the vacuum chamber 2 . The moving unit 4 includes a pair of guide rails 4a and a carrier 5 that moves while being supported by the pair of guide rails 4a. Each guide rail 4a extends in the X direction, and a pair of guide rails 4a are spaced apart in the Y direction. The moving unit 4 has a driving mechanism such as a linear motor and a ball screw mechanism, and the driving force of the driving mechanism moves the carrier 5 along the pair of guide rails 4a as indicated by the solid and broken lines in FIG. 1(B). Reciprocate in the X direction.

The carrier 5 has a holding portion 5a that holds the substrate 100. As shown in FIG. A substrate 100 is transported into the vacuum chamber 2 from the entrance gate 2a and held by the carrier 5 . The movement of the carrier 5 causes the substrate 100 to move horizontally in the vacuum chamber 2 in the X direction. During the movement, sputtered particles scattered from the target 6 are deposited on the lower surface of the substrate 100 to form a film. The film-formed substrate 100 is carried out of the vacuum chamber 2 through the exit gate 2b.

In the case of this embodiment, the target 6 is a rotating target rotatable around a rotation center line C1 in the Y direction. A target 6 is supported by a pair of support bases 10 . A motor 11 is provided on one support table 10, and the target 6 is rotated by the driving force of the motor 11 using the motor 11 as a driving source.

The target 6 has a cylindrical shape, and a cathode electrode 7 is provided on the inner peripheral surface thereof. Moreover, 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 6 is arranged above the internal space of the target 6 .

The 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 an annular magnet having a pair of linear portions extending in the Y direction parallel to the central magnet 9a and connecting portions connecting both ends of the pair of linear portions in the Y direction. A) and the like show cross sections of a pair of straight portions of the peripheral magnet 9b.

The central magnet 9a and the peripheral magnet 9b have opposite polarities, and the magnetization direction of the central magnet 9a is the direction of the central reference line N0. The center reference line NO is a straight line that passes through the center of the magnetic pole of the center magnet 9a in the X direction and extends in the direction orthogonal to the surface of the target 6 (the radial direction of the target 6). In the case of this embodiment, the center reference line NO is a line that extends in the Z direction, passes through the rotation center line C1 of the target 6, and is perpendicular to the transfer surface of the substrate 100. FIG. The magnetization direction of the peripheral magnet 32 extends parallel to the central magnet 9a, and the inner ends of the central magnet 9a and the peripheral magnet 9b are connected by a yoke 9c. As a result, the magnetic field near the surface of the target 6 has magnetic lines of force returning in a loop from the magnetic pole of the central magnet 9a toward the linear portion of the peripheral magnet 9b. This magnetic field traps electrons and concentrates the plasma near the surface of the target 6, increasing the efficiency of sputtering.

The shielding member 12 is positioned between the substrate 100 and the target 6 and is a deposition-inhibiting member that structurally restricts the scattering range of sputtered particles to the substrate 100 during film formation. The shielding member 12 is a rotating body that has an outer peripheral surface to which sputtered particles adhere and is rotatable around the rotation center line C2 in the Y direction. The shield member 12 is supported by a pair of support bases 10 directly above the target 6 . The central reference line N0 passes through the shielding member 12 and, in particular, the rotation centerline C2. A motor 14 is provided on one support base 10 , and the shielding member 12 rotates independently of the target 6 by the driving force of the motor 14 using the motor 14 as a driving source.

In the case of this embodiment, the shielding member 12 has a cylindrical shape, and the anode electrode 13 is provided on the inner peripheral surface of the shielding member 12, which has the effect of stabilizing the plasma. Stabilization of the plasma, which affects the deposition rate, can reduce variations in film thickness between substrates and improve part stoppage. The anode electrode 13 is maintained at the anode potential (earth potential, the same potential as the wall of the vacuum chamber 2).

The sputtering apparatus 1 has a cooling unit 15 that cools the shielding member 12 . The cooling unit 15 has a circulation unit 15a arranged outside the vacuum chamber 2, and a pipe 15b extending through the wall of the vacuum chamber 2 and the support base 10 on the other side to the shielding member 12. The pipe 15b is a U-shaped pipe that extends inside the shielding member 12 from one end to the other end in the Y direction, turns back, and extends from the other end to the one end. The circulation unit 15a includes a pump that circulates a cooling medium such as water between the circulation unit 15a and the pipe 15b, and a heat exchanger that exchanges heat with the circulating cooling medium to keep the temperature of the cooling medium constant. include. By cooling the shielding member 12 , sputtered particles adhering to the shielding member 12 can be prevented from scattering to the substrate 100 .

In this embodiment, the shielding member 12 is cooled through the pipe 15b. It is also possible to cool the shielding member 12 . In this case, the shielding member 12 is subjected to insulation treatment with respect to the anode electrode 13 and sealing treatment to prevent leakage of the cooling medium.

The sputtering device 1 has a control unit 16 . The control unit 16 includes at least one processor, at least one storage device, and an interface for inputting/outputting data with sensors and actuators, and controls the sputtering apparatus 1 . The storage device is memory such as RAM and ROM, for example. The processor executes programs stored in the storage device, and controls the driving of the motors 11 and 14 and the moving unit 4, and the like.

<Deposition operation>
A film formation operation of the sputtering apparatus 1 will be described with reference to FIG. While the substrate 100 is continuously moved by the moving unit 4, the sputtered particles P are scattered from the target 6 to the substrate 100 and deposited on the lower surface of the substrate 100 to form a film. An elliptical loop L near the surface of the target 6 shown in FIG. 2(A) schematically shows a portion where the plasma concentrates. It is known that the plasma density is high at a position where the magnetic flux density component in the direction normal to the surface of the target 6 is zero, and the sputtered particles are scattered intensively. This point is located between the straight portions of the central magnet 31 and the peripheral magnet 32 . The distribution of the deposition rate, which is the amount of deposition per unit time when the sputtered particles emitted from the target 6 are deposited on the transport surface, has a peak near the central reference line N0, and is distributed upstream and downstream in the X direction. It becomes a mountain-shaped distribution in which the rate decreases.

In this embodiment, since the shielding member 12 is positioned on the central reference line N0, the scattering range of the sputtered particles P is restricted near the central reference line N0. Therefore, the scattering range is the range on both sides of the shielding member 12 in the X direction where the film formation rate is relatively low. Sputtered particles that scatter in the range on both sides of the shielding member 12 in the X direction tend to scatter in the D1 direction or the D2 direction that is inclined with respect to the normal direction (Z direction) of the substrate 100 . As illustrated in FIG. 2A, when the bottom surface of the substrate 100, which is the film formation surface, has unevenness, the sputtered particles scattered in the D1 direction or the D2 direction are likely to be deposited on the uneven side surface, and the side coverage can be improved. .

During film formation, the motors 11 and 14 are driven, and the target 6 and shielding member 12 are continuously rotated (rotated) in the directions of arrows R1 and R2 (clockwise), for example. As described above, the deposition rate is high near the central reference line N0, and the deposition amount of sputtered particles on the shielding member 12 increases. Generally, in such a configuration, the shielding member has a short life and needs to be replaced frequently. This is because when the film thickness increases, the dimensions of the shielding member including the film change, the scattering range fluctuates, and the film easily peels off and adheres to the surface of the target 6, which can cause particle generation. be.

However, in this embodiment, the shielding member 12 rotates, and the area facing the target 6 (in this embodiment, the range of about 60 degrees on both sides in the X direction (120 degrees in total) around the central reference line N0) is cyclic. is changed to Since the deposition surface of the sputtered particles on the shielding member 12 can be made wider, the increase in film thickness can be delayed. That is, the replacement frequency of the shielding member 12 can be reduced. By rotating the shielding member 12 continuously, it is possible to prevent the film thickness from partially changing, and to extend the life of the shielding member 12 .

<Second embodiment>
In the first embodiment, the shielding member 12 is rotated continuously during film formation, but may be stopped during film formation and rotated when a predetermined rotation condition is satisfied. In other words, it may be rotated intermittently. The rotation conditions are, for example, each substrate, each substrate, each predetermined time, and each operator's rotation instruction. FIG. 2B is an explanatory diagram thereof. In the illustrated example, film formation is performed on the substrate 100 while the rotation of the shielding member 12 is stopped as shown in state ST1. A film is formed on the outer peripheral surface of the shielding member 12 by partially depositing the sputtered particles (on the lower part). When the rotation condition is established, the shielding member 12 is rotated as shown in state ST2. The amount of rotation is, for example, the amount by which the area facing the target 6 is replaced (120 degrees in the configuration of the first embodiment).

Even when the shielding member 12 is rotated intermittently in this manner, the replacement frequency of the shielding member 12 can be reduced.

Moreover, the rotation of the shielding member 12 may be performed manually without being automated by the motor 14 . In the case of manual operation, for example, the rotating shaft of the shielding member 12 may pass through the side wall of the vacuum chamber 2 and extend outside so that the operator can manually rotate the rotating shaft.

<Third Embodiment>
In the first embodiment, the target 6 and the shielding member 12 are provided with the motors 11 and 14 as driving sources, respectively, but one motor may be shared to rotate the target 6 and the shielding member 12 . FIG. 3A shows an example of the mechanism.

A gear 18 is provided on the output shaft of the shared motor 17 . The target 6 and the shielding member 12 are provided with gears 19 and 20 on their central axes of rotation, respectively. By driving the motor 17, the target 6 and the shielding member 12 can be rotated simultaneously. The rotation speed ratio of the target 6 and the shielding member 12 can also be adjusted by the gear ratio of the gears 18-20.

In the example of FIG. 3A, a gear mechanism is used as a mechanism for transmitting driving force from the shared motor 17 to the target 6 and the shielding member 12, but other mechanisms such as a belt transmission mechanism may be used.

<Fourth embodiment>
Although the cylindrical shielding member 12 is illustrated in the first embodiment, the shielding member 12 may have a rectangular tubular shape. FIG. 3B shows an example thereof. In the illustrated example, the shielding member 12 has a prismatic cross-sectional shape, and its outer peripheral surface is composed of five planes. As in the illustrated example, film formation is performed on the substrate 100 with one of the five planes facing the target 6 . A different plane can be made to face the target 6 by rotating the shielding member 12 by 72 degrees. In the case of this embodiment, by intermittently rotating the shielding member 12 as described in the second embodiment, five planes of the shielding member 12 are sequentially rotated while maintaining the uniformity of the scattering range of the sputtered particles P. can be utilized.

<Fifth embodiment>
In the first embodiment, the targets 6 and shielding members 12 are arranged vertically, but other arrangements can be adopted. FIG. 4A shows an example thereof. In the illustrated example, the shielding member 12 is arranged at a position shifted in the X direction from the position right above the target 6 . Also, the magnet 9 is arranged such that the center reference line N0 thereof is inclined upstream in the direction of transport of the substrate 100 from the Z direction. The shielding member 12 regulates the scattering range of the sputtered particles P in a region where the film formation rate is relatively low. Immediately after entering the scattering range of the sputtered particles P, the substrate 100 is positioned on the central reference line N0 where the film formation rate is high, so that a thick film can be formed from the initial stage of film formation.

Further, in the example of FIG. 4A, the pipes 15b are arranged vertically. By setting the lower pipe 15b on the cooling medium supply side and the upper pipe 15b on the cooling medium discharge side, the cooling performance of the shielding member 12 on the target 6 side can be improved.

<Sixth Embodiment>
In the first embodiment, the moving unit 4 that moves the substrate 100 in the X direction was exemplified as a unit that relatively moves the substrate 100, the shielding member 12, and the target 6 during film formation. and the target 6 may be moved. FIG. 4B shows an example thereof.

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 movable in the X direction. A pair of support bases 10 are mounted on sliders 23 . The moving unit 21 has a driving mechanism such as a linear motor and a ball screw mechanism, and the driving force of the driving mechanism reciprocates the slider 23 along the pair of guide rails 22 between the solid line position and the broken line position in the X direction. Let The position of the substrate 100 is stopped during film formation. While the slider 23 is moved, sputtered particles are emitted from the target 6 to form a film on the substrate 100 .

In the example of FIG. 4B as well, the pipes 15b are arranged vertically. By setting the lower pipe 15b on the cooling medium supply side and the upper pipe 15b on the cooling medium discharge side, the cooling performance of the shielding member 12 on the target 6 side can be improved.

<Seventh embodiment>
Although the rotating target 6 is exemplified as the target 6 in the first embodiment, a flat target may be used. FIG. 5 shows an example thereof. In the illustrated example, a flat target 25 is provided instead of the rotating target 6 . The configuration of the magnet 9 is basically the same as that of the first embodiment. In the example of FIG. 5 as well, the pipes 15b are arranged vertically. By setting the lower pipe 15b on the cooling medium supply side and the upper pipe 15b on the cooling medium discharge side, the cooling performance of the shielding member 12 on the target 25 side can be improved.

Further, in the first embodiment, the configuration in which the sputtered particles are emitted to the substrate above the target was exemplified, but the configuration may be such that the sputtered particles are emitted to the substrate below the target.

<Other embodiments>
The present invention supplies a program that implements one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and one or more processors in the computer of the system or apparatus reads and executes the program. It can also be realized by processing to It can also be implemented by a circuit (for example, ASIC) that implements one or more functions.

The invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the claims are appended to make public the scope of the invention.

1 sputtering device, 6 target, 12 shielding member, 100 substrate

Claims (7)

a target for scattering sputtered particles onto the substrate;
a shielding member positioned between the substrate and the target for controlling a scattering range of sputtered particles with respect to the substrate during film formation;
A sputtering apparatus comprising
The shielding member is a rotating body having an outer peripheral surface,
By rotating the shielding member, a region of the outer peripheral surface facing the target is changed.
A sputtering device characterized by: The sputtering apparatus according to claim 1,
The shielding member has a cylindrical shape,
A sputtering device characterized by: The sputtering apparatus according to claim 1,
a driving source that outputs driving force to rotate the shielding member;
and a control means for controlling the drive source,
A sputtering device characterized by: A sputtering apparatus according to claim 3,
the target is a rotating target;
The drive source is a common drive source for rotation of the shielding member and rotation of the target.
A sputtering device characterized by: The sputtering apparatus according to any one of claims 1 to 4,
Further comprising cooling means for cooling the shielding member,
A sputtering device characterized by: The sputtering apparatus according to any one of claims 1 to 5,
The sputtering device is a magnetron sputtering device,
the shielding member is maintained at an anodic potential and the target is maintained at a cathodic potential,
A sputtering device characterized by: The sputtering apparatus according to any one of claims 1 to 6,
moving means for relatively moving the substrate, the shielding member, and the target during film formation;
A sputtering device characterized by:

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